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This document provides an overview and comparison of 1G, 2G, 3G, 4G, and 5G mobile network technologies. It describes the key features and limitations of each generation of technology. 4G is highlighted as providing significantly higher data speeds and capacity over 3G, as well as always-on internet access. However, 4G also faces limitations around supporting large numbers of users and battery life. 5G is introduced as aiming to support speeds over 1Gbps, provide global accessibility, and be more cost-effective than 4G. The document concludes that 5G will fulfill increasing user demands and lead to a fully wireless world.
Mobile communication systems have evolved from 1G to 4G over several generations, with each generation bringing major improvements. 1G systems provided basic mobile voice calling. 2G introduced digital networks and services like texting. 3G focused on higher speed data and the beginning of mobile broadband. 4G aims to provide high-speed broadband to support a wide range of services for high mobility applications. The document provides an overview of this evolution from 1G analog networks to the emerging 4G standards.
Wireless phone standards have a life of their own. You can tell, because they are spoken of reverently in terms of generations. There's Great-Granddad, whose pioneering story pre-dates cellular; Grandma and Grandpa 1G, or analog cellular, Mom and Dad 2G, or digital cellular; 3G wireless, 4G, 5G and so on. This is a survey report on this technologies.
Review and Analysis of WiMAX Technology using different Modulation scheme wit...ijtsrd
The last few decades, there has been a incredible growth in the wireless communication technology. The growing demand of multimedia services and the growth of Internet related contents lead to increasing interest to high speed communications. The Wireless communication technology, affordable wireless service has become a reality. In wireless communication, radio propagation refers to the behavior of radio waves when they are propagated from transmitter to receiver. In the course of propagation, radio waves are mainly affected by three different modes of physical phenomena: reflection, diffraction, and scattering. In this paper, we analysis of MIMO-OFDM system employing different Modulation scheme is analysed using AWGN channel. The Simulation results show that this is a novel technique for next generation wireless systems using MATLAB toll R2013a. Arvind Yadav | Er. Praveen Kumar Patidar"Review and Analysis of WiMAX Technology using different Modulation scheme with AWGN Channel" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: http://www.ijtsrd.com/papers/ijtsrd11662.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/11662/review-and-analysis-of-wimax-technology-using-different-modulation-scheme-with-awgn-channel/arvind-yadav
This document is a seminar report on 4G broadband technology presented by P. Satya. It includes an introduction to 4G and the evolution of mobile radio standards from 1G to 3G. Key aspects of 4G technology discussed include standards, benefits over 3G including higher data rates, hardware components like OFDM and advanced antenna systems, and software components like software defined radio. The report provides details on technologies enabling 4G like orthogonal frequency division multiplexing, ultra-wideband networks, and adaptive modulation and power control.
Evolution of Wireless Communication TechnologiesAkhil Bansal
This report comprises of detailed analysis how the wireless communication developed from 1G to 4G LTE to improve data services for the end user.The future ahead i.e. 5G is also discussed.
Feel free to discuss, would be happy to help.
5 G SYSTEMS IS THE FUTURE WILL BE FAST WITH UNIMAGINABLE SPEED AND WITH LOTS OF SERVICES.Though 5G is still in development stage it has lots of promising features that will definitely change our future. For this data hungry and speed loving generation 5G will definitely be the hottest technology and it will certainly make our future really exciting. In this article we will see how the mobile networks have evolved and what will be the future of mobile network and of course about 5G network.
This document is a thesis submitted by three students - Farjana Islam, Umme Salma Munmun, and Zareen Rahman - for their Bachelor of Science degree in Computer Science and Engineering. The thesis is titled "A Study on 3G Mobile Technology". It was submitted to and accepted by the Board of Examiners of the Department of Computer Science and Engineering at Manarat International University. The thesis analyzes and compares 3G mobile networks and services to previous generations, highlighting the impact of 3G technology on life, society, and technology in Bangladesh. It discusses the evolution from 2G to 3G standards and the migration challenges faced in implementing 3G networks.
This document provides an overview and comparison of 1G, 2G, 3G, 4G, and 5G mobile network technologies. It describes the key features and limitations of each generation of technology. 4G is highlighted as providing significantly higher data speeds and capacity over 3G, as well as always-on internet access. However, 4G also faces limitations around supporting large numbers of users and battery life. 5G is introduced as aiming to support speeds over 1Gbps, provide global accessibility, and be more cost-effective than 4G. The document concludes that 5G will fulfill increasing user demands and lead to a fully wireless world.
Mobile communication systems have evolved from 1G to 4G over several generations, with each generation bringing major improvements. 1G systems provided basic mobile voice calling. 2G introduced digital networks and services like texting. 3G focused on higher speed data and the beginning of mobile broadband. 4G aims to provide high-speed broadband to support a wide range of services for high mobility applications. The document provides an overview of this evolution from 1G analog networks to the emerging 4G standards.
Wireless phone standards have a life of their own. You can tell, because they are spoken of reverently in terms of generations. There's Great-Granddad, whose pioneering story pre-dates cellular; Grandma and Grandpa 1G, or analog cellular, Mom and Dad 2G, or digital cellular; 3G wireless, 4G, 5G and so on. This is a survey report on this technologies.
Review and Analysis of WiMAX Technology using different Modulation scheme wit...ijtsrd
The last few decades, there has been a incredible growth in the wireless communication technology. The growing demand of multimedia services and the growth of Internet related contents lead to increasing interest to high speed communications. The Wireless communication technology, affordable wireless service has become a reality. In wireless communication, radio propagation refers to the behavior of radio waves when they are propagated from transmitter to receiver. In the course of propagation, radio waves are mainly affected by three different modes of physical phenomena: reflection, diffraction, and scattering. In this paper, we analysis of MIMO-OFDM system employing different Modulation scheme is analysed using AWGN channel. The Simulation results show that this is a novel technique for next generation wireless systems using MATLAB toll R2013a. Arvind Yadav | Er. Praveen Kumar Patidar"Review and Analysis of WiMAX Technology using different Modulation scheme with AWGN Channel" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: http://www.ijtsrd.com/papers/ijtsrd11662.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/11662/review-and-analysis-of-wimax-technology-using-different-modulation-scheme-with-awgn-channel/arvind-yadav
This document is a seminar report on 4G broadband technology presented by P. Satya. It includes an introduction to 4G and the evolution of mobile radio standards from 1G to 3G. Key aspects of 4G technology discussed include standards, benefits over 3G including higher data rates, hardware components like OFDM and advanced antenna systems, and software components like software defined radio. The report provides details on technologies enabling 4G like orthogonal frequency division multiplexing, ultra-wideband networks, and adaptive modulation and power control.
Evolution of Wireless Communication TechnologiesAkhil Bansal
This report comprises of detailed analysis how the wireless communication developed from 1G to 4G LTE to improve data services for the end user.The future ahead i.e. 5G is also discussed.
Feel free to discuss, would be happy to help.
5 G SYSTEMS IS THE FUTURE WILL BE FAST WITH UNIMAGINABLE SPEED AND WITH LOTS OF SERVICES.Though 5G is still in development stage it has lots of promising features that will definitely change our future. For this data hungry and speed loving generation 5G will definitely be the hottest technology and it will certainly make our future really exciting. In this article we will see how the mobile networks have evolved and what will be the future of mobile network and of course about 5G network.
This document is a thesis submitted by three students - Farjana Islam, Umme Salma Munmun, and Zareen Rahman - for their Bachelor of Science degree in Computer Science and Engineering. The thesis is titled "A Study on 3G Mobile Technology". It was submitted to and accepted by the Board of Examiners of the Department of Computer Science and Engineering at Manarat International University. The thesis analyzes and compares 3G mobile networks and services to previous generations, highlighting the impact of 3G technology on life, society, and technology in Bangladesh. It discusses the evolution from 2G to 3G standards and the migration challenges faced in implementing 3G networks.
This document discusses wireless communication technologies. It provides an overview of wireless communication types including wired and wireless. It describes the evolution of wireless technologies through four generations (1G to 4G) and discusses multiple access techniques like FDMA and TDMA. The document also outlines advantages of wireless technologies and examples of applications including infrared, Bluetooth, Wi-Fi and WiMax.
1. The document discusses the evolution of wireless mobile communication networks from 1G to 5G.
2. 1G networks were the first generation of analog cellular networks introduced in the 1980s. They supported only voice calls with speeds up to 2.4 kbps.
3. 2G networks introduced digital cellular technology in the late 1980s, allowing for improved voice quality, data services like texting, and more efficient use of spectrum. GSM became the dominant 2G standard globally.
This document discusses the role of cognitive radio technology in 4G communications. It begins with an abstract that introduces cognitive radio as the key enabling technology for next generation networks. It then reviews research being done on cognitive radio and 4G technologies. The main possibilities of implementing cognitive radios in 4G communication systems are surveyed, including how networks like IEEE 802.22 and WiMAX extensions can enhance 4G performance using cognitive technologies.
1) The 1st generation (1G) of mobile networks in the 1980s used analog signals and had disadvantages like poor voice quality and limited capacity.
2) The 2nd generation (2G) digital networks beginning in 1991 had benefits like encrypted calls and new data services like texting. Technologies included GSM, CDMA, and TDMA.
3) Improvements like 2.5G's GPRS and 2.75G's EDGE enabled faster data rates and limited web browsing between 2G and 3G.
A survey on multiple access technologies beyond fourth generation wireless co...ijceronline
The future of mobile wireless communication networks will include existing 3rd generation, 4th generation 5th generation,6th generation (with very high data rates Quality of Service (QoS) and service applications) and 7th generation (with space roaming). Mobile and wireless networks have made tremendous growth in the last fifteen years. The rapid improvement of the mobile generations was for the purpose of supporting as many mobile devices as possible that could benefit the users at anytime and anywhere in terms of common practical applications such as internet access, video-ondemand, video conferencing system and many more applications. This paper is focused on the specifications of future generations and latest technologies to be used in future wireless mobile communication networks like MIMO, OFDM, OFDMA, Massive MIMO, LTE, LTE-A.
The document discusses 4G mobile communications standards including WiMAX and LTE. It provides information on:
- IEEE 802.22 which uses white spaces in TV frequencies for wireless regional area networks.
- Requirements for 4G standards defined by ITU including peak speeds of 1Gbps.
- How early versions of Mobile WiMAX and LTE did not meet the full 4G requirements but were still branded as 4G.
- Mobile WiMAX Release 2 and LTE Advanced promising speeds of 1Gbps in 2013.
The document provides an overview of the evolution of wireless networks from 1G to 5G. It describes the key characteristics of each generation: 1G used analog signals for voice only, while 2G introduced digital cellular networks with improved voice quality and new data capabilities. 2G networks had higher capacity and security compared to 1G. 3G networks further improved data speeds and allowed new applications like video calls. 4G aims to provide wireless internet access at broadband speeds, while 5G envisions seamless global coverage with no limitations on connectivity.
The document discusses the evolution of wireless networks from 1G to 5G. 1G networks were the first generation of cellular networks and used analog signals. 2G introduced digital cellular networks like GSM, which offered benefits over 1G like encrypted calls and greater efficiency. 3G networks brought internet access to mobile phones. 4G aims to provide wireless internet with speeds comparable to fixed broadband. 5G networks will integrate existing cellular and WiFi networks to provide universal wireless connectivity without limitations.
SPECIAL SECTION ON RECENT ADVANCES IN SOFTWARE DEFINED NETWORKING FOR 5G NETW...Rakesh Jha
In the near future, i.e., beyond 4G, some of the prime objectives or demands that need to
be addressed are increased capacity, improved data rate, decreased latency, and better quality of service.
To meet these demands, drastic improvements need to be made in cellular network architecture. This paper
presents the results of a detailed survey on the fth generation (5G) cellular network architecture and some
of the key emerging technologies that are helpful in improving the architecture and meeting the demands of
users. In this detailed survey, the prime focus is on the 5G cellular network architecture, massive multiple
input multiple output technology, and device-to-device communication (D2D). Along with this, some of the
emerging technologies that are addressed in this paper include interference management, spectrum sharing
with cognitive radio, ultra-dense networks, multi-radio access technology association, full duplex radios,
millimeter wave solutions for 5G cellular networks, and cloud technologies for 5G radio access networks
and software dened networks. In this paper, a general probable 5G cellular network architecture is proposed,
which shows that D2D, small cell access points, network cloud, and the Internet of Things can be a part of
5G cellular network architecture. A detailed survey is included regarding current research projects being
conducted in different countries by research groups and institutions that are working on 5G technologies.
Millimeter wave mobile communications for 5 g CellularPoornima E.G.
This document summarizes research on using millimeter wave frequencies for 5G cellular networks as a solution to address increasing bandwidth demands. It discusses how directional antennas and wider channel bandwidth at mm-wave frequencies could enable multi-gigabit mobile data speeds. The document also reviews myths around rain attenuation at mm-wave bands and shows that for small cell sizes of 200m, rain impact is minimal. It presents motivation, methodology and initial measurement results showing 28GHz and 38GHz can be used for cellular with directional antennas.
5G Technology stands for the 5th Generation Mobile technology. 5G is a next major phase of mobile telecommunications standards beyond the 4G standards. 5G is expected to provide speed upto 10Gbit/s, wider frequency band,
high increased peak bit rate, high system spectral efficiency, ubiquitous connectivity and a significant increase in QoS as
compared to current 4G technology. Evolution of mobile communication technology to 5G is discussed in this review, followed by protocol stack and 5G architecture. A wide comparison is given between the various generations so as to compare why 5G technology is better and needed.
IRJET- A Review on Mobile Computing Wireless Communication Technology using 0...IRJET Journal
This document provides a review of mobile computing and wireless communication technologies from 0G to 7G. It begins with an abstract that outlines the evolution of mobile wireless generations. The body then discusses each generation in more detail, describing the key technologies, features, and advancements of 0G, 1G, 2G, 3G, 4G, 5G, 6G, and 7G. The review concludes that research is ongoing into future 6G and 7G technologies to further improve upon capabilities introduced in previous generations.
Birja seminar -Challenges in the Migration to 4G Birja Guia
The document discusses the challenges in migrating from 3G to 4G mobile networks. It identifies several key challenges: (1) Developing multimode user terminals that can adapt to different wireless networks. This is challenging due to limitations in antenna and processing technology. (2) Ensuring terminal mobility across networks through efficient location management and seamless handoff between cells. (3) Supporting quality of service guarantees and security across different network infrastructures and technologies. (4) Developing billing systems that can accommodate users subscribing to multiple services from multiple providers through a single billing method. The document also outlines research needed to address these challenges and develop solutions to enable the transition to fully integrated 4G networks.
Third generation (3G) mobile networks allow for improved voice quality, higher data speeds, and additional services compared to previous generations. The document discusses the evolution of wireless technologies from 1G to 4G networks and how each generation offers improved performance and capabilities over the prior generation. 3G introduced the ability to access the internet, send multimedia messages, and use location-based services from mobile devices. [/SUMMARY]
This document discusses 4G technology and its advantages over previous generations of wireless networks. 4G networks will provide significantly higher data rates of up to 1 Gbps for stationary users and 100 Mbps for mobile users. They will be fully IP-based and allow seamless integration of various wireless technologies including cellular, WiFi, and Bluetooth. Key technologies enabling 4G networks include OFDM, MIMO, and adaptive modulation and coding. 4G will support multimedia applications like mobile TV, video chat, and provide anytime, anywhere access to services like voice, data, GPS. Some examples of 4G applications mentioned are virtual presence, virtual navigation, and telemedicine.
4G was introduced in the early 2000s. The idea was to perpetuate the logic of replacing one mobile generation with another every 10 years.4G mobile is yet established as increasing data transfer speeds, 4G mobile should use enhanced security measures. Another goal is to reduce blips in transmission when a device moves between areas covered by different networks. 4G mobile networks should also use a network based on the IP address system used for the internet.
Evolution of Wireless Communication TechnologiesAkhil Bansal
Detailed presentation on Wireless Communication Technologies.
The communication technology has evolved to provide lower latency network, faster and efficient data services.
Here is the link to the complete report on "Wireless Communication Generations"
"https://drive.google.com/folderview?id=0BxLQQCpBqGHiaHlvLW1xeEtja2c&usp=sharing"
VYSA’s Got Talent 2013 - “Tìm kiếm tài năng Việt tại Nhật 2013” là chương trình dành riêng cho cộng đồng người Việt Nam đang sinh sống, học tập và làm việc tại xứ sở hoa anh đào do Hội Thanh niên Sinh viên Việt Nam tại Nhật (VYSA) đăng cai tổ chức.
O documento lista os artilheiros e gols marcados de vários times na Super Copa Gaúcha de 2014. O jogador com mais gols foi Cidinho da Cerâmica com 4 gols. Romário marcou 3 gols pelo Internacional e Brenner e Kayron marcaram 3 gols cada pelo Juventude. Vários outros jogadores marcaram 2 ou menos gols para seus respectivos times.
This document discusses wireless communication technologies. It provides an overview of wireless communication types including wired and wireless. It describes the evolution of wireless technologies through four generations (1G to 4G) and discusses multiple access techniques like FDMA and TDMA. The document also outlines advantages of wireless technologies and examples of applications including infrared, Bluetooth, Wi-Fi and WiMax.
1. The document discusses the evolution of wireless mobile communication networks from 1G to 5G.
2. 1G networks were the first generation of analog cellular networks introduced in the 1980s. They supported only voice calls with speeds up to 2.4 kbps.
3. 2G networks introduced digital cellular technology in the late 1980s, allowing for improved voice quality, data services like texting, and more efficient use of spectrum. GSM became the dominant 2G standard globally.
This document discusses the role of cognitive radio technology in 4G communications. It begins with an abstract that introduces cognitive radio as the key enabling technology for next generation networks. It then reviews research being done on cognitive radio and 4G technologies. The main possibilities of implementing cognitive radios in 4G communication systems are surveyed, including how networks like IEEE 802.22 and WiMAX extensions can enhance 4G performance using cognitive technologies.
1) The 1st generation (1G) of mobile networks in the 1980s used analog signals and had disadvantages like poor voice quality and limited capacity.
2) The 2nd generation (2G) digital networks beginning in 1991 had benefits like encrypted calls and new data services like texting. Technologies included GSM, CDMA, and TDMA.
3) Improvements like 2.5G's GPRS and 2.75G's EDGE enabled faster data rates and limited web browsing between 2G and 3G.
A survey on multiple access technologies beyond fourth generation wireless co...ijceronline
The future of mobile wireless communication networks will include existing 3rd generation, 4th generation 5th generation,6th generation (with very high data rates Quality of Service (QoS) and service applications) and 7th generation (with space roaming). Mobile and wireless networks have made tremendous growth in the last fifteen years. The rapid improvement of the mobile generations was for the purpose of supporting as many mobile devices as possible that could benefit the users at anytime and anywhere in terms of common practical applications such as internet access, video-ondemand, video conferencing system and many more applications. This paper is focused on the specifications of future generations and latest technologies to be used in future wireless mobile communication networks like MIMO, OFDM, OFDMA, Massive MIMO, LTE, LTE-A.
The document discusses 4G mobile communications standards including WiMAX and LTE. It provides information on:
- IEEE 802.22 which uses white spaces in TV frequencies for wireless regional area networks.
- Requirements for 4G standards defined by ITU including peak speeds of 1Gbps.
- How early versions of Mobile WiMAX and LTE did not meet the full 4G requirements but were still branded as 4G.
- Mobile WiMAX Release 2 and LTE Advanced promising speeds of 1Gbps in 2013.
The document provides an overview of the evolution of wireless networks from 1G to 5G. It describes the key characteristics of each generation: 1G used analog signals for voice only, while 2G introduced digital cellular networks with improved voice quality and new data capabilities. 2G networks had higher capacity and security compared to 1G. 3G networks further improved data speeds and allowed new applications like video calls. 4G aims to provide wireless internet access at broadband speeds, while 5G envisions seamless global coverage with no limitations on connectivity.
The document discusses the evolution of wireless networks from 1G to 5G. 1G networks were the first generation of cellular networks and used analog signals. 2G introduced digital cellular networks like GSM, which offered benefits over 1G like encrypted calls and greater efficiency. 3G networks brought internet access to mobile phones. 4G aims to provide wireless internet with speeds comparable to fixed broadband. 5G networks will integrate existing cellular and WiFi networks to provide universal wireless connectivity without limitations.
SPECIAL SECTION ON RECENT ADVANCES IN SOFTWARE DEFINED NETWORKING FOR 5G NETW...Rakesh Jha
In the near future, i.e., beyond 4G, some of the prime objectives or demands that need to
be addressed are increased capacity, improved data rate, decreased latency, and better quality of service.
To meet these demands, drastic improvements need to be made in cellular network architecture. This paper
presents the results of a detailed survey on the fth generation (5G) cellular network architecture and some
of the key emerging technologies that are helpful in improving the architecture and meeting the demands of
users. In this detailed survey, the prime focus is on the 5G cellular network architecture, massive multiple
input multiple output technology, and device-to-device communication (D2D). Along with this, some of the
emerging technologies that are addressed in this paper include interference management, spectrum sharing
with cognitive radio, ultra-dense networks, multi-radio access technology association, full duplex radios,
millimeter wave solutions for 5G cellular networks, and cloud technologies for 5G radio access networks
and software dened networks. In this paper, a general probable 5G cellular network architecture is proposed,
which shows that D2D, small cell access points, network cloud, and the Internet of Things can be a part of
5G cellular network architecture. A detailed survey is included regarding current research projects being
conducted in different countries by research groups and institutions that are working on 5G technologies.
Millimeter wave mobile communications for 5 g CellularPoornima E.G.
This document summarizes research on using millimeter wave frequencies for 5G cellular networks as a solution to address increasing bandwidth demands. It discusses how directional antennas and wider channel bandwidth at mm-wave frequencies could enable multi-gigabit mobile data speeds. The document also reviews myths around rain attenuation at mm-wave bands and shows that for small cell sizes of 200m, rain impact is minimal. It presents motivation, methodology and initial measurement results showing 28GHz and 38GHz can be used for cellular with directional antennas.
5G Technology stands for the 5th Generation Mobile technology. 5G is a next major phase of mobile telecommunications standards beyond the 4G standards. 5G is expected to provide speed upto 10Gbit/s, wider frequency band,
high increased peak bit rate, high system spectral efficiency, ubiquitous connectivity and a significant increase in QoS as
compared to current 4G technology. Evolution of mobile communication technology to 5G is discussed in this review, followed by protocol stack and 5G architecture. A wide comparison is given between the various generations so as to compare why 5G technology is better and needed.
IRJET- A Review on Mobile Computing Wireless Communication Technology using 0...IRJET Journal
This document provides a review of mobile computing and wireless communication technologies from 0G to 7G. It begins with an abstract that outlines the evolution of mobile wireless generations. The body then discusses each generation in more detail, describing the key technologies, features, and advancements of 0G, 1G, 2G, 3G, 4G, 5G, 6G, and 7G. The review concludes that research is ongoing into future 6G and 7G technologies to further improve upon capabilities introduced in previous generations.
Birja seminar -Challenges in the Migration to 4G Birja Guia
The document discusses the challenges in migrating from 3G to 4G mobile networks. It identifies several key challenges: (1) Developing multimode user terminals that can adapt to different wireless networks. This is challenging due to limitations in antenna and processing technology. (2) Ensuring terminal mobility across networks through efficient location management and seamless handoff between cells. (3) Supporting quality of service guarantees and security across different network infrastructures and technologies. (4) Developing billing systems that can accommodate users subscribing to multiple services from multiple providers through a single billing method. The document also outlines research needed to address these challenges and develop solutions to enable the transition to fully integrated 4G networks.
Third generation (3G) mobile networks allow for improved voice quality, higher data speeds, and additional services compared to previous generations. The document discusses the evolution of wireless technologies from 1G to 4G networks and how each generation offers improved performance and capabilities over the prior generation. 3G introduced the ability to access the internet, send multimedia messages, and use location-based services from mobile devices. [/SUMMARY]
This document discusses 4G technology and its advantages over previous generations of wireless networks. 4G networks will provide significantly higher data rates of up to 1 Gbps for stationary users and 100 Mbps for mobile users. They will be fully IP-based and allow seamless integration of various wireless technologies including cellular, WiFi, and Bluetooth. Key technologies enabling 4G networks include OFDM, MIMO, and adaptive modulation and coding. 4G will support multimedia applications like mobile TV, video chat, and provide anytime, anywhere access to services like voice, data, GPS. Some examples of 4G applications mentioned are virtual presence, virtual navigation, and telemedicine.
4G was introduced in the early 2000s. The idea was to perpetuate the logic of replacing one mobile generation with another every 10 years.4G mobile is yet established as increasing data transfer speeds, 4G mobile should use enhanced security measures. Another goal is to reduce blips in transmission when a device moves between areas covered by different networks. 4G mobile networks should also use a network based on the IP address system used for the internet.
Evolution of Wireless Communication TechnologiesAkhil Bansal
Detailed presentation on Wireless Communication Technologies.
The communication technology has evolved to provide lower latency network, faster and efficient data services.
Here is the link to the complete report on "Wireless Communication Generations"
"https://drive.google.com/folderview?id=0BxLQQCpBqGHiaHlvLW1xeEtja2c&usp=sharing"
VYSA’s Got Talent 2013 - “Tìm kiếm tài năng Việt tại Nhật 2013” là chương trình dành riêng cho cộng đồng người Việt Nam đang sinh sống, học tập và làm việc tại xứ sở hoa anh đào do Hội Thanh niên Sinh viên Việt Nam tại Nhật (VYSA) đăng cai tổ chức.
O documento lista os artilheiros e gols marcados de vários times na Super Copa Gaúcha de 2014. O jogador com mais gols foi Cidinho da Cerâmica com 4 gols. Romário marcou 3 gols pelo Internacional e Brenner e Kayron marcaram 3 gols cada pelo Juventude. Vários outros jogadores marcaram 2 ou menos gols para seus respectivos times.
El documento describe los diferentes tipos de memoria en un ordenador, incluyendo la memoria RAM, ROM, CMOS y caché. La memoria RAM puede leerse y escribirse y se usa para programas y datos temporales, mientras que la memoria ROM solo puede leerse y almacena el firmware básico. La memoria CMOS es una RAM alimentada por batería para mantener la configuración cuando el ordenador está apagado, y la memoria caché acelera las operaciones del procesador.
Interference Revelation in Mobile Ad-hoc Networks and Confrontationirjes
In this paper, we utilize the Several interference revelation techniques proposed for mobile ad hoc
networks rely on each node passively monitoring the data forwarding by its next hop. This paper presents
quantitative evaluations of false positives and their impact on monitoring based interference revelation for ad
hoc networks. Experimental results show that, even for a simple three-node configuration, an actual ad-hoc
network suffers from high false positives; these results are validated by Markov and probabilistic models.
However, this false positive problem cannot be observed by simulating the same network using popular ad hoc
network simulators, such as ns-2, OPNET or Glomosim. To remedy this, a probabilistic noise generator model
is implemented in the Glomosim simulator. With this revised noise model, the simulated network exhibits the
aggregate false positive behavior similar to that of the experimental tested. Simulations of larger (50-node) ad
hoc networks indicate that monitoring-based interference revelation has very high false positives. These false
positives can reduce the network performance or increase the overhead. In a simple monitoring-based system
where no secondary and more accurate methods are used, the false positives impact the network performance in
two ways: reduced throughput in normal networks without attackers and inability to mitigate the effect of
attacks in networks with attackers.
A simulation and analysis of secured aodv protocol in mobile ad hoc networkseSAT Journals
Abstract A Mobile ad hoc Network is a wireless network, which is dynamic in nature, that can be simulated by infra structure less connections in which every node itself can act as a router. There are many significant routing protocols proposed for providing significant benefits in terms of performance, reliability, security and many other issues also have been addressed. An efficient way of evaluating the performance of MANETS is to simulate them. Of the many simulators available, Ns-2 has gained increasing popularity because of its many efficient features. The main aim of this simulator is to provide better networking environment for research and educational purposes. In this paper, we try to propose a new routing protocol and tried to implement it on NS-2 . We also tried to compare the results with other protocols. Keywords: MANET, AODV, Network Simulator, DSR
Design and development of load sharing multipath routing protcol for mobile a...eSAT Journals
Abstract Routing in Mobile Ad hoc Networks (MANETs) is a challenging task due to the dynamic nature of the network topology and resource constraints. Due to communication over wireless channel, participating nodes also experience interference and bandwidth constraints. Therefore it is essential to develop a robust and efficient routing protocol for MANETs. This research paper involves design and development of a multipath routing protocol for MANETs, called Load Sharing Multipath Routing (LS-MPR) uses dual polarized directional antenna to enhance network efficiency and provide load balancing. LS-MPR is an on-demand multipath routing protocol, which selects best possible multiple paths based on ascending order of hop count and availability of common polarization between neighboring mobile nodes. The performance of the LS-MPR is compared with that Ad-hoc On Demand Distance Vector (AODV) and Dynamic Source Routing (DSR). The network performance is checked with and without node mobility, throughput, Packet Delivery Ratio (PDR), least jitter, low interference and low end-to-end delay. Directional antenna is a very efficient and low cost smart antenna technology. It can achieve better performance, higher throughput, and better resource utilization with omnidirectional antennas multi-path routing cannot be exploited very well since packets routed on one of the paths cause an interference zone that typically encompasses the other paths and thereby limits the number of packets routed on these paths. Keywords: Multipath Routing, Load Sharing Multipath Routing (LS-MPR) Ad-hoc On Demand Distance Vector (AODV) Dynamic Source Routing (DSR).
Definition
A decentralized type of wireless network, allowing people and devices to seamlessly internetwork in areas with no pre-existing communication infrastructure, It can turn the dream of networking at any place and at time into reality. We are almost there by the way .Ex- Bluetooth enabled mobile phones such as 3G, laptops, handheld digital devices, personal digital assistants, or wearable computers
The document discusses routing protocols in mobile ad hoc networks. It describes the characteristics of ad hoc networks and why routing is different compared to traditional networks due to factors like host mobility and dynamic topology. The document categorizes and explains examples of different types of routing protocols including table-driven, on-demand, and hybrid protocols. It provides examples of specific protocols like DSDV, AODV, DSR, and ZRP and compares their key aspects.
Use of NS-2 to Simulate MANET Routing AlgorithmsGiancarlo Romeo
The document summarizes the use of the NS-2 network simulator to simulate mobile ad hoc network (MANET) routing algorithms. It describes creating scenarios of mobile nodes, generating network traffic between nodes, running simulations of different routing protocols, and analyzing the resulting trace files to calculate throughput. Key aspects covered include the NS-2 architecture, scenario and traffic generation procedures, simulation and analysis procedures, and options configured for the simulations.
This document provides an overview and tutorial on using the ns-2 network simulator. It covers the basics of ns-2 including its architecture, using OTcl and C++, event-driven simulation, tracing packets, creating network topologies, inserting errors, setting up routing, creating connections using TCP and applications, and visualizing simulations using Nam. The tutorial aims to help users understand the basic concepts of ns-2, set up their own network topologies and simulations, add traffic, run simulations, and use visualization tools.
Ns-2 is a discrete event network simulator used for modeling wired and wireless network protocols. It has two main components - the C++ simulator engine for fast packet-level processing, and the OTcl scripting language for configuration and control. Simulation involves setting up nodes, links, agents, applications and traffic before scheduling events and running the simulation. Traces can then be analyzed to evaluate network performance.
An ad hoc network is a type of wireless network that does not require a central router or base station. Nodes communicate directly with each other or through intermediate nodes in a multi-hop fashion without any fixed infrastructure. Routing and resource management are distributed. Common types include wireless mesh networks, wireless sensor networks, and hybrid wireless networks. Ad hoc networks face challenges related to medium access, routing, security, and resource constraints due to the lack of centralized control.
This document is a master's thesis that explores vehicular ad hoc networks (VANETs) through simulations. It contains 11 chapters that cover topics like wireless technology standards, the AODV routing protocol, network simulation tools, traffic simulation, connectivity analysis in VANETs, secure broadcasting protocols, and hybrid internet access in VANETs. The thesis evaluates these topics through simulations using the NS-2 network simulator and a multi-agent traffic simulator to model VANETs on highways and in urban environments.
The document discusses ad hoc networks and wireless sensor networks. It defines an ad hoc network as a temporary network composed of mobile nodes without preexisting infrastructure that is self-organizing. Wireless sensor networks are introduced as a collection of sensor nodes densely deployed to monitor conditions and cooperatively pass data back to central nodes. The document outlines key characteristics of both networks including their temporary and adaptive nature, multi-hop routing, and challenges of mobility, power constraints, and dynamic topology changes.
ZigBee is a wireless networking standard focused on low-cost, low-power consumption devices for monitoring and control applications. It uses the IEEE 802.15.4 standard for the physical and MAC layers and provides data rates from 20-250kbps depending on frequency band. ZigBee networks can support hundreds of devices with flexible star, peer-to-peer, or cluster tree topologies and address devices using short or IEEE addresses. The technology is well-suited for wireless control in industrial, commercial, and home automation applications where low data rates and power usage are priorities.
Mobile communication systems have evolved from 1G to 4G over several generations, with each generation bringing major improvements. 1G systems provided basic mobile voice calling. 2G introduced digital networks and services like texting. 3G focused on higher speed data and the beginning of mobile broadband. 4G aims to provide high-speed broadband to support a wide range of services for high mobility applications. The document provides an overview of this evolution from 1G analog networks to the emerging 4G standards.
Mobile Networking and Ad hoc routing protocols validationIOSR Journals
This document discusses mobile networking and ad hoc routing protocols. It begins with an overview of cellular phone networks and their growth in usage. It then describes mobile ad hoc networks and some of the challenges in designing routing protocols for them. The document evaluates two model checking tools, SPIN and UPPAAL, and discusses their ability to verify properties of ad hoc routing protocols through formal validation methods.
This document provides an overview of 4G technology, including its goals of drastically increasing data transfer speeds and reducing transmission interruptions when moving between networks. It discusses technologies that fall under the 4G umbrella such as UMTS, OFDM, MIMO, and WiMAX. It also outlines some problems with 4G including potential interference with other devices and an inability to keep up with demand growth.
4G (Fourth Generation) Mobile System is an expected system that aims at integrating present wireless networking technologies and to be give support to these different technologies in order to solve the pending challenges facing the present wireless technologies. The 4G mobile system is a vision under research that is proposed to be out in the year 2010, there is news that claims that there are headways made already, and that there are some systems with the expected features of 4G but it is yet to be seen.
This document provides an overview of the evolution of mobile network technologies from 2G to 5G, including:
- 2G networks provided limited data and were circuit-switched, while 2.5G networks like GPRS used packet switching. 3G aimed to support higher speeds up to 2Mbps but faced challenges.
- 4G networks are IP-based and aim to provide broadband access and seamless global roaming. Technologies like HSPDA and IMS help support higher data rates and multimedia services.
- 5G is envisioned to fully support wireless internet applications through technologies enabling flexible dynamic ad-hoc networks, with speeds over 100Mbps. It represents both evolutionary improvements and revolutionary capabilities like
5G is the next generation of wireless technology that will provide significantly faster data speeds, reduced latency, and the ability to connect many more devices simultaneously. The document discusses the evolution of wireless technologies from 1G to 5G, providing details on the key features and capabilities of each generation. It then describes the proposed 5G architecture and working, highlighting aspects like its IP-based design, use of cognitive radio technology, and open wireless and transport protocols. The remaining sections cover the expected features, advantages, challenges and applications of 5G networks.
The document discusses the concepts of 5G cellular networks and cognitive radio (CR). It proposes combining the two technologies, with 5G terminals being CR terminals. The key points are:
1) 5G aims to interconnect all existing wireless technologies into a single high-performance worldwide network, while CR allows secondary users to access unused spectrum.
2) CR offers a way to integrate different wireless technologies functionally, providing a complete 5G wireless access network.
3) CR technology could represent future 5G terminals and implement the "WISDOM" concept of integrating wireless networks by providing new control planes, protocols, and improved network monitoring, adaptation, and performance.
(3G) Technology, one of the leading Technologies in today’s wireless technology. NTT DoCoMo of Japan on October 1, 2001 is the first one to commercially launch this service. It was first implemented on CDMA phones. Now this service is coming with GSM. Third Generation (3G) mobile devices and services will transform wireless communications into on-line, real-time connectivity. 3G wireless technology will allow an individual to have immediate access to location-specific services that offer information on demand.
This document provides a comparative study of Bluetooth, 802.11, and HIPERLAN wireless standards. It begins with an introduction to wireless LAN standards and classifications of wireless LANs. It then discusses key aspects of various wireless standards, including IEEE 802.11, HIPERLAN, and Bluetooth. It compares their operating frequencies, data transmission rates, and other technical specifications. The document also includes figures illustrating wireless network architectures and standards. In conclusion, it provides a brief literature review on topics related to planning, designing, and implementing wireless local area networks.
Performance Analysis of WiMAX and LTE Using NS-2IJERA Editor
The increasing use of wireless devices and in particular smart phones has resulted the need for greater capacity
and higher speed than the existing network technologies. Hence, LTE (Long Term Evolution) and WiMAX
(Worldwide Interoper- ability for Microwave Access) became the two leading technologies. Services are
increasingly shifting from voice to data and from circuit-switched to packet-switched ones. Battle between LTE
and WiMAX technologies is already heating up with WiMAX being ahead due to availability of standards
through IEEE 802.16 and is up and running but lacks in substantial roll out plans due to cost. The targets for
LTE indicate bandwidth increases as high as 100 Mbps on the downlink, and up to 50 Mbps on the uplink.
However, this potential increase in bandwidth is just a small part of the overall improvement LTE aims to
provide. This study illustrates the model and representation of LTE links and traffics using NS-2 network
simulator and observation of TCP performance investigated. The Evaluation of the network performance with
TCP is mainly based on congestion window behavior, throughput, average delay and lost packet.
Performance comparison of umts and lte on the basis of data ratesIAEME Publication
This document compares the 3G and 4G mobile communication technologies of UMTS and LTE. UMTS (3G) uses WCDMA technology and has a maximum theoretical downlink speed of 42Mbps, while LTE (4G) uses OFDM and more advanced MIMO schemes, providing much higher maximum theoretical downlink speeds of 100Mbps with the ability to reach 1Gbps. The document outlines the network architectures and standards of UMTS and LTE. It also lists the objectives of 4G networks in providing improved quality of service, mobility, bandwidth and a fully IP-based network compared to 3G technologies.
Today wireless services are the most preferred services of the world. The rapid increase in
the service is due to the advancement of technology consecutively. As a subscriber becomes more
aware of the mobile phone technology, he/she will seek for an appropriate package all together, and
including all the advanced features of a cellular phone can have. Hence, the search for new
technology is always the main intention of the prime cell phone giants to out innovate their
competitors. In addition, the main purpose of the fifth generation wireless networks (5G Wireless
networks) is planned to design the best wireless world that is free from limitations and hindrance of
the previous generations. 5G technologies will change the way most high bandwidth users access
their Mobile Radio Communication (MRC). So, this paper represents, great evolution of 1G (First
Generation) to 4G yield 5G, introduction to 5G technologies, why there is a need for 5G, advantages
of 5G networks technology, exceptional applications, Quality of Service (QoS), 5G network
architecture.
Frontiers of Wireless and Mobile CommunicationsSai Varrshini
This document discusses emerging wireless technologies and their impact. It provides an overview of key technologies like MIMO, cooperative communications, and dynamic spectrum access. It summarizes the evolution of radio technologies from 2G to 4G standards and increasing link speeds. It also examines short-range wireless technologies and research challenges in building cognitive radios and software-defined radios to efficiently utilize spectrum.
Frontiers of wireless and mobile communications v0.02Sai Varrshini
The document discusses a paper on frontiers in wireless technology. It describes how wireless transmission has reached billions of bits per second and mobile services have become internet-based. Emerging technologies like dynamic spectrum access, software-defined radio and MIMO have the potential to increase radio link speeds from MBps to GBps and support new networking concepts. The paper examines the impact of these wireless techniques on audiovisual and multimedia applications.
Mobile computing allows users to access network services from anywhere at any time using portable devices. It involves using computers while on the move, enabling connectivity and new applications anywhere infrastructure exists. Key challenges include disconnections, low bandwidth, security risks, and supporting a variety of devices. Future advances may include artificial intelligence, smaller devices through integrated circuitry, and faster processors. Open areas remain around interference, regulations, bandwidth limitations, and security in shared environments. Mobile generations have progressed from 1G analog cellular to 2G digital cellular to 3G supporting high-speed data and 4G aims for all-IP networks with speeds over 100Mbps.
Mobile computing allows users to access network services and computational resources from anywhere using portable devices like laptops, smartphones, and tablets. It is defined as computing using portable devices that maintain network connectivity while on the move. Mobile computing faces challenges like low bandwidth, disconnection, and security risks compared to wired networks. Future advancements may include increased use of artificial intelligence and integrated circuits to develop more compact devices with faster processors. Mobile computing has transitioned through generations from 1G analog cellular to 2G digital cellular to 3G broadband cellular and beyond to 4G and 5G.
NTT DoCoMo and the Future Implications of HighLuke Markey
NTT DoCoMo has pioneered 4G mobile networks through its domestic ecosystem in Japan. The document discusses the evolution of mobile networks from 1G to 4G, highlighting NTT DoCoMo's innovations. Key aspects of NTT DoCoMo's 4G network include using existing frequency carrier technology from older standards to increase bandwidth, and adopting the LTE-Advanced standard to build upon existing 3G infrastructure through gradual upgrades. This allows for a simpler transition to fully realizing the goals of 4G networks for high-speed mobile broadband.
The document discusses 5G mobile technologies and the evolution of networks from 1G to 5G. Some key points:
1) 5G will provide significantly higher bandwidth and data transmission rates compared to previous generations. It will allow seamless connectivity globally.
2) Each generation (1G to 5G) provides improved technologies over the last, increasing bandwidth, functionality and connectivity. 5G will be based on an all-IP infrastructure using IPv6 to provide uniform services.
3) 5G aims to use network resources more efficiently through techniques like combining bandwidth from multiple overlapping networks and intelligent distribution of internet access within buildings.
The document compares LTE and WiMAX technologies. It discusses their evolution from earlier standards to 4G versions (LTE-Advanced and WiMAX 2.0). While technically similar, some key differences that gave LTE an advantage included LTE's shorter frame duration which enabled lower latency, as well as its earlier standardization and broader operator support. Looking forward, WiMAX plans to integrate with LTE in a heterogeneous network approach, as LTE has become the dominant 4G standard.
This document provides an overview of next generation wireless communication technologies, focusing on 5G. It discusses the evolution from 1G to 4G wireless standards. 5G aims to support higher bandwidth, lower latency, and more connections than previous standards. 5G works using millimeter waves, small cell networks, and beamforming to direct signals. Key features of 5G include speeds over 1 Gbps, low latency under 1 ms, increased bandwidth and device connectivity, near 100% coverage and availability, and reduced energy usage. While 5G promises major improvements, it may also enable laziness and reduce productivity if overused.
Similar to IJCER (www.ijceronline.com) International Journal of computational Engineering research (20)
Driving Business Innovation: Latest Generative AI Advancements & Success StorySafe Software
Are you ready to revolutionize how you handle data? Join us for a webinar where we’ll bring you up to speed with the latest advancements in Generative AI technology and discover how leveraging FME with tools from giants like Google Gemini, Amazon, and Microsoft OpenAI can supercharge your workflow efficiency.
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Guest Speaker Segment with Hannah Barrington: Dive into the world of dynamic real estate marketing with Hannah, the Marketing Manager at Workspace Group. Hear firsthand how their team generates engaging descriptions for thousands of office units by integrating diverse data sources—from PDF floorplans to web pages—using FME transformers, like OpenAIVisionConnector and AnthropicVisionConnector. This use case will show you how GenAI can streamline content creation for marketing across the board.
Ollama Use Case: Learn how Scenario Specialist Dmitri Bagh has utilized Ollama within FME to input data, create custom models, and enhance security protocols. This segment will include demos to illustrate the full capabilities of FME in AI-driven processes.
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Your One-Stop Shop for Python Success: Top 10 US Python Development Providersakankshawande
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For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/how-axelera-ai-uses-digital-compute-in-memory-to-deliver-fast-and-energy-efficient-computer-vision-a-presentation-from-axelera-ai/
Bram Verhoef, Head of Machine Learning at Axelera AI, presents the “How Axelera AI Uses Digital Compute-in-memory to Deliver Fast and Energy-efficient Computer Vision” tutorial at the May 2024 Embedded Vision Summit.
As artificial intelligence inference transitions from cloud environments to edge locations, computer vision applications achieve heightened responsiveness, reliability and privacy. This migration, however, introduces the challenge of operating within the stringent confines of resource constraints typical at the edge, including small form factors, low energy budgets and diminished memory and computational capacities. Axelera AI addresses these challenges through an innovative approach of performing digital computations within memory itself. This technique facilitates the realization of high-performance, energy-efficient and cost-effective computer vision capabilities at the thin and thick edge, extending the frontier of what is achievable with current technologies.
In this presentation, Verhoef unveils his company’s pioneering chip technology and demonstrates its capacity to deliver exceptional frames-per-second performance across a range of standard computer vision networks typical of applications in security, surveillance and the industrial sector. This shows that advanced computer vision can be accessible and efficient, even at the very edge of our technological ecosystem.
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
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Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
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The original Czech 🇨🇿 version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
Discover top-tier mobile app development services, offering innovative solutions for iOS and Android. Enhance your business with custom, user-friendly mobile applications.
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5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
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Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
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Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
-Insightful presentations covering two practical applications of the Power Grid Model.
-An update on the latest advancements in Power Grid -Model technology during the first and second quarters of 2024.
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Conversational agents, or chatbots, are increasingly used to access all sorts of services using natural language. While open-domain chatbots - like ChatGPT - can converse on any topic, task-oriented chatbots - the focus of this paper - are designed for specific tasks, like booking a flight, obtaining customer support, or setting an appointment. Like any other software, task-oriented chatbots need to be properly tested, usually by defining and executing test scenarios (i.e., sequences of user-chatbot interactions). However, there is currently a lack of methods to quantify the completeness and strength of such test scenarios, which can lead to low-quality tests, and hence to buggy chatbots.
To fill this gap, we propose adapting mutation testing (MuT) for task-oriented chatbots. To this end, we introduce a set of mutation operators that emulate faults in chatbot designs, an architecture that enables MuT on chatbots built using heterogeneous technologies, and a practical realisation as an Eclipse plugin. Moreover, we evaluate the applicability, effectiveness and efficiency of our approach on open-source chatbots, with promising results.
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Northern Engraving | Nameplate Manufacturing Process - 2024Northern Engraving
Manufacturing custom quality metal nameplates and badges involves several standard operations. Processes include sheet prep, lithography, screening, coating, punch press and inspection. All decoration is completed in the flat sheet with adhesive and tooling operations following. The possibilities for creating unique durable nameplates are endless. How will you create your brand identity? We can help!
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Join us to learn how UiPath Apps can directly and easily interact with prebuilt connectors via Integration Service--including Salesforce, ServiceNow, Open GenAI, and more.
The best part is you can achieve this without building a custom workflow! Say goodbye to the hassle of using separate automations to call APIs. By seamlessly integrating within App Studio, you can now easily streamline your workflow, while gaining direct access to our Connector Catalog of popular applications.
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Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
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This presentation will help you understand the power of Microsoft 365. However, we have mentioned every productivity app included in Office 365. Additionally, we have suggested the migration situation related to Office 365 and how we can help you.
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The Microsoft 365 Migration Tutorial For Beginner.pptx
IJCER (www.ijceronline.com) International Journal of computational Engineering research
1. International Journal Of Computational Engineering Research (ijceronline.com) Vol. 2 Issue. 5
Mobile Networking and Ad hoc networking technologies
1
Simanta Sarma, 2Dr. Sarbananda Das
1
(HOD & Asstt. Professor, Department of Computer Science, S.B.M.S College, Sualkuchi, Assam, India)
2
(Rtd. Principal, North Gauhati College, North Guwahati, Assam, India)
Abstract: In this paper we describe mobile network & mobile ad hoc networking technology. Moreover we discuss
generation of mobile network and a lean and efficient routing protocol for wireless ad hoc networks. We report on its
implementation, on performance comparisons and on a formal validation result. Moreover we discuss Formal Protocol
Verification and operating over infrared or Bluetooth. This paper evaluates two model checking tools, SPIN and
UPPAAL, using the verification of the Ad hoc Routing protocol as a case study. Insights are reported in terms of
identifying important modeling considerations and the types of ad hoc protocol properties that can realistically be verified.
Keywords. Cellular Phone network, mobile ad hoc networks, routing protocols, Wireless networks, ad hoc routing,
routing protocol Implementation, formal validation, model checking, Infrared or Bluetooth.
1. INTRODUCTION:
Cellular communications has experienced explosive growth in the past two decades. Today millions of people around the
world use cellular phones. In modern area Cellular phones are most important factor in human life. Cellular phones allow
a person to make or receive a call from almost anywhere. Likewise, a person is allowed to continue the phone
conversation while on the move. Cellular communications is supported by an infrastructure called a cellular network,
which integrates cellular phones into the public switched telephone network. Cellular service has seen tremendous
acceptance, especially in the last few years, with millions of new subscribers each year and the new subscriber rate
growing. Some estimates predict that half a billion cellular phones will be in service by the end of the next decade. AD-
HOC networks are typically described as a group of mobile nodes connected by wireless links where every node is both a
leaf node and a router.
1.1 EVOLUTION OF MOBILE NETWORKS:
The first systems offering mobile telephone service (car phone) were introduced in the late 1940s in the United States and
in the early 1950s in Europe. Those early single cell systems were severely constrained by restricted mobility, low
capacity, limited service, and poor speech quality. The equipment was heavy, bulky, expensive, and susceptible to
interference. Because of those limitations, less than one million subscribers were registered worldwide by the early 1980s.
1.1.1 GENERATIONS OF MOBILE COMMUNICATION:
1G (First Generation):
The introduction of cellular systems in the late 1970s and early 1980s represented a big leap in mobile communication
especially in capacity and mobility. Semiconductor technology and microprocessors made smaller, lighter weight and
more sophisticated mobile systems a practical reality for many more users. These 1G cellular systems still transmit only
analog voice information. The most prominent 1G system is Advanced Mobile Phone System (AMPS), Nordic Mobile
Telephone (NMT), and Total Access Communication System (TACS).
2G (Second Generation):
The development of 2G cellular systems was driven by the need to improve transmission quality, system capacity, and
coverage. 2G cellular systems include GSM, Digital AMPS (D-AMPS), code division multiple access (CDMA), IS-95
and Personal Digital Communication (PDC). The most important distinction in 1G and 2G is that 1G networks use analog
signals, while 2G networks use digital. Today, multiple 1G and 2G standards are used in worldwide mobile
communications. Many standards are used only in one country or region, and most are incompatible. GSM is the most
successful family of cellular standards (GSM900, GSM–railway [GSM–R], GSM1800, GSM1900, and GSM400).
3G (Third Generation):
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3G systems promise faster communications services, including voice, fax and Internet, anytime and anywhere with
seamless global roaming. The first 3G network was deployed in Japan in 2001. 3G technology supports 144 Kbps
bandwidth, with high speed movement (e.g. vehicles), 384 Kbps (e.g. on campus) & 2 Mbps for stationary. "True" 3G
Third-generation specifications call for even higher speeds 144 kbps in vehicles, 384 Kbps for pedestrians outdoors, and
2.48 Mbps in indoor offices. Some carriers are calling their current deployments 3G. This is contested by others as being
the lowest rung of the 3G specification, and hence prefers to use the term 2.5G. As expected, each of the 2.5G
technologies has a forward path to the 3rd generation.
EDGE (Enhanced Data Rates for Global [or GSM] Evolution) is the true 3G offering along the GSM path. It provides
data rates three times greater than GSM/GPRS, with speeds in the range 100 - 130 kbps (up to 200 kbps in bursts).
EDGE was rolled out across Canada in 2004. Being an extension of GSM/GPRS, EDGE will be widely available
internationally, and supported by network operators in many countries, and over 60 network operators in over 40
countries have committed to EDGE for their next generation services.
There are a couple of forward paths from CDMA2000 offering substantially higher data rates. Neither of the CDMA
based carriers (Telus Mobility, Bell Mobility) had announced offerings or pilots at the time or writing.
Next Generation
There are specifications for higher speed services. We will update you when these become closer to reality in
Canada.
1.2. BRIEF HISTORY
Many channel allocation algorithms have been proposed during the last thirty years for cellular networks to avoid channel
interference and efficiently utilize the limited frequencies. These algorithms can be classified into three types: fixed,
flexible, and dynamic. Among them, dynamic channel allocation (DCA) strategies have been the focus of recent research.
With DCA strategies, a cell may use any channel that will not cause channel interference. Typically, each channel is
associated with a priority; when a cell needs a channel, it picks the available channel which has the highest priority. All
the previous algorithms, which are referred to as centralized channel allocation algorithms, rely on a mobile switching
centre (MSC) to accomplish channel allocation.
2. MOBILE AD-HOC NETOWRK
Theoretical mobile ad hoc networking research [CCL03] started some decades ago. But commercial digital radio
echnologies appeared in the mid-nineties. Since then, few proposal for enabling ad hoc communications were made. The
first technology (IEEE802.11, also referred to as Wi-Fi [ANS99]) is still strongly leading the market, although there is
great room for improvement. This section provides an overview and a technical description of the technologies that have
been proposed hitherto. A common feature of most wireless networking technologies is that they operate in the unlicensed
Industrial Scientific and Medical (ISM) 2.4GHz band. Because of this choice of frequency band, the network can suffer
interferences from microwave ovens, cordless telephones, and other appliances using this same band plus, of cours, other
networks. In particular, Farrell and Abukharis studied the impact on Bluetooth on IEEE802.11g [ST04]
2.1 Packet radio
Packet radio [GFS78] was used for the earliest versions of mobile ad hoc networks. It was sponsored by DARPA in the
1970s. It allows the transmission of digital data over amateur radio channels. Using special radio equipment, packet radio
networks allowing transmissions at 19.2 kbit/s, 56 kbit/s, and even 1.2 Mbit/s have been developed. Since the modems
employed vary in the modulation techniques they use, there is no standard for the physical layer of packet radio networks.
Packet radio networks use the AX.25 data link layer protocol, derived from the X.25 protocol suite and designed for
amateur radio use. AX.25 has most frequently been used to establish direct, point-topoint links between packet radio
stations, without any additional network layers. However, in order to provide routing services, several network layer
protocols have been developed for use with AX.25. Most prominent among these are NET/ROM, ROSE, and TexNet. In
principle, any network layer protocol may be used, including the Internet protocol (IP), which was implemented in the
framework of the AMPRNet project.
2.2 IEEE802.11
Wi-Fi is a wireless networking technology based on the IEEE802.11 specifications. The first—and still most used—Wi-Fi
standard is referred to as IEEE802.11b in the scientific literature. It was then declined into IEEE802.11a, IEEE802.11g
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and IEEE802.11n. IEEE802.11i and IEEE802.11h, which respectively focus on Quality of Service (QoS) and security, are
out of the scope of this document. All Wi-Fi technologies operate on the 2.4GHz band, except from IEEE802.11a which
operates within the 5GHz band. These technologies use significantly different PHY layers which, from the user point of
view, make them differ in term of the bandwidth (i.e. the data rate) that they provide. Typically, Wi-Fi enabled devices
have coverage distances ranging from 50 to more than 100 meters. In practice, this coverage distance depends greatly on
the nature of the antenna and on the environment in which the devices evolve.
2.2.1 IEEE802.11a
IEEE802.11a uses Orthogonal Frequency Division Multiplexing (OFDM). It is the only wireless radio technology that
works in the 5GHz band. The main idea behind OFDM is that since low-rate modulations (i.e modulations with relatively
long symbols compared to the channel time characteristics) are less sensitive to multipath, it should be better to send a
number of low rate streams in parallel than sending one high rate waveform. OFDM then works by dividing one high-
speed signal carrier into several lower-speed subcarriers, which are transmitted in parallel. High-speed carriers, which are
20MHz wide, are divided into 52 sub channels, each approximately 300KHz wide. OFDM uses 48 of these sub channels
for transporting data, while the four others are used for error correction. OFDM delivers higher data rates and a high
degree of multipath reflection reconstruction, thanks to its encoding scheme and error correction.
2.2.2 IEEE802.11b
IEEE 802.11b uses Direct Sequence Spread Spectrum (DSSS) as the physical layer technique for the standard. DSSS uses
a complex technique which consists in multiplying the data being transmitted by a noise signal. This noise signal is a
pseudo-random sequence of 1 and −1 values, at a frequency much higher than the original signal. The resulting signal
wave looks much like white noise. This white noise can be filtered at the receiving end in order to recover the original
data. This filtering happens by again multiplying the same pseudo-random sequence by the received signal (because 1 ×
1= 1, and −1 × −1 = 1). This process, known as ―de-spreading‖, mathematically constitutes a correlation of the
transmitted pseudo-random sequence with the receiver’s assumed sequence. For allowing de-spreading to work correctly,
the transmit and received sequences must synchronized. So far, IEEE 802.11b is the implementation of the IEEE 802.11
standard that has been most heavily studied in the framework of mobile ad hoc networks.
2.2.3 IEEE802.11g
IEEE802.11g, just like IEEE802.11a, uses orthogonal frequency-division multiplexing (OFDM), it then boasts similar
bandwidths. OFDM is described in Section 2.2.1. But unlike IEEE802.11a, IEEE802.11g works in the 2.4 GHz band.
Since the draft 802.11g standard combines fundamental features from both 802.11a and 802.11b, it leads to the
development of devices that can inter-operate with technologies based on both of the previous versions of the
specification.
2.3 Bluetooth
Bluetooth is essentially the same kind of microwave radio technology that has given us wireless door chimes and
automatic garage door openers. It was initially restricted to an operating distance of just 10 meters and a speed of
approximately 1 Mbit/s. When Bluetooth devices come within range of each other, they establish contact and form a
temporary network called a Personal Area Network (PAN). In the Bluetooth terminology, this is also known as a Pico net.
A multi-hop ad hoc network formed by the interaction of Bluetooth devices is called a Scatter net. When using Bluetooth,
the devices must establish a network session before being able to transmit any data. Bluetooth uses the Frequency-
Hopping Spread Spectrum (FHSS) technique. Unlike IEEE802.11 which establishes a communication link on a certain
frequency (a channel), FHSS breaks the data down into small packets and transfers it on a wide range of frequencies
across the available frequency band. Bluetooth transceivers jump among 79 hop frequencies in the 2.4 GHz band at the
rate of 1,600 frequency hops per second. 10 different types of hopping sequences are defined, 5 of the 79 MHz range/79
hop system and 5 for the 23 MHz range/23 hop system.
This technique trades off bandwidth, in order to be robust and secure. More precisely, Spread Spectrum communication
techniques have been used for many years by the military because of their security capabilities.
2.4 Hiperlan
The HiperLAN2 standard is very close to 802.11a/g in terms of the physical layers it uses—both use OFDM technology—
but is very different at the MAC level and in the way the data packets are formed and devices are addressed. On a
technical level, whereas 802.11a/g can be viewed as true wireless Ethernet, HiperLAN2 is more similar to wireless
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Asynchronous Transfer Mode (ATM). It operates by sharing the 20MHz channels in the 5GHz spectrum in time, using
Time Division Multiple Access (TDMA) to provide QoS through ATM-like mechanisms. It supports two basic modes of
operation: centralized mode and direct mode. The centralized mode is used in the cellular networking topology where
each radio cell is controlled by an access point covering a certain geographical area.
2.5 ZigBee
ZigBee-enabled devices conform to the IEEE 802.15.4-2003 standard. This standard specifies its lower protocol layers,
the physical layer (PHY), and the medium access control (MAC). It targets Low-Rate Wireless Personal Area Network
(WPAN). ZigBee-style networks research began in 1998. Zigbee was intended to operate in contexts in which both Wi-Fi
and Bluetooth are not suitable. Zigbee operates in the unlicensed 2.4 GHz, 915 MHz and 868 MHz ISM bands. It uses
direct-sequence spread spectrum (DSSS) coding. This makes the data rate to reach 250 kbit/s per channel in the 2.4 GHz
band, 40 kbit/s per channel in the 915 MHz band, and 20 kbit/s in the 868 MHz band. The maximum output power of
ZigBee antennas being generally 1 mW, the transmission range of ZigBee nodes is between 10 and 75 meters.
Observations have shown that the transmission range is heavily dependent on the environment.
2.6 Broadband wireless networking
WiMAX (IEEE 802.16) stands for Worldwide Interoperability for Microwave Access. IEEE 802.16 boasts data rates up
to 70 Mbit/s over a distance of 50 km. However practical limits from real world tests seem to be between 500 kbit/s and 2
Mbit/s at a distance of around 5-8kms. WiBro is a wireless broadband internet technology being developed by the Korean
telecoms industry. It has been announced that WiBro base stations will offer an aggregate data throughput of 30 to 50
Mbit/s and cover a radius of up to 5 km. The technology will also offer Quality of Service.
HIPERMAN [HPF03, HPF04], which stands for High Performance Radio Metropolitan Area Network, is a European
alternative to WiMAX. The standards were created by the European Telecommunications Standards Institute (ETSI). It
provides a wireless network communication in the 2-11 GHz bands. The adequation of these technologies to ad hoc
networking is discussable, since they would permit to establish ad hoc networking at a level at which technologies for
infrastructure networks (like GSM or UMTS) are available.
3. Protocol Validation
3.1 Survey of Methods
Computer networking protocol validation is commonly done using a combination of simulation and testing. These are
both valid approaches that to some extent complement each other. Simulation offers the possibility to run a large batch of
tests under identical circumstances whereby some parameter can be varied and the effect studied. A very common
assisting tool, or framework, is the network simulator - ns-2 [26]. Live testing is often applied to some extent during
protocol development. An important application for the method is when checking interoperability between different
implementations. Live testing poses the difficulty of conducting several comparable tests, but if done in a structured way
it may very well expose errors or problems not visible in simulations. The gray zone problem, reported by Lundgren et al.
[34] is one example of such a discrepancy. In Paper C initial results from a structured live testing study are presented. The
tool we use is called the APE testbed [38]. A third alternative is to use formal verification in order to be sure to cover all
situations possible in a system model. Testing and simulation are not exhaustive methods and cannot guarantee that there
are no undiscovered subtle errors or design flaws in a protocol. The objective of formal verification is to improve on
reliability by reasoning about systems using mathematical logic. A formal system model can thereby be checked to fully
comply with a given set of requirements. There have been comparatively few efforts at formal verification of ad hoc
routing protocols. The reason for this is twofold. First, there is the presumption that the methods are difficult to use which
is to some extent true since there really is a threshold to cross before becoming proficient. The deductive methods usually
require more experience before it is possible to carry out a proof for a non trivial system. Even then, it is often a very time
consuming process. In the case of deductive methods they have a potential to be very powerful and can be used to
construct proofs for large or even infinite state systems. However, the proof may be notoriously difficult to find or it may
not even exist because the problem is not well formulated. Algorithmic verification methods, commonly known as model
checking [9], have been more successful in terms of industrial deployment because of their easier usage. These methods
have another problem that surfaces for systems composed from a set of different components that can interact in a non
deterministic manner. Many possible interleaving of execution are thereby possible, leading to exponential growth of the
searched state space; the state explosion problem [47]. These new techniques thus have the potential for verifying infinite
state systems automatically by abstract interpretation [15] followed by, for example, symbolic model checking [36]. There
is ongoing work on many fronts in order to lower the threshold of use as well as on coping with the state explosion
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problem. Here, we concentrate on some of the more user friendly tools, namely automatic model checkers. Our hope is to
advocate the use of formal verification by the average protocol designer.
3.2 Formal Protocol Verification
3.2.1 System Description Languages
In order to verify a particular protocol it first has to be described in a structured and unambiguous way. For this, there are
two main choices. Either, one can write an implementation in a regular programming language such as C and thereafter
verify the code directly. This approach has been used by Engler and Musuvathi [18] to find errors in different AODV
implementations. It is most often not used for exhaustive verification but rather as a method of finding program bugs,
even though Engler and Musuvathi were also able to identify a routing loop error in the AODV specification. The second
approach to describing the protocol is to use a formal description language. This can either be a subset of first order
predicate logic or some more high level formalism such as PROMELA (PROcess Meta LAnguage) used in the SPIN [23]
tool. In reality, these languages are just representations of transition systems. It is essential that the formal description
matches that of the real system implementation, but normally some parts have to be abstracted away from in order to
make the problem feasible for verification. In the case of deductive verification the proof may otherwise be too difficult to
construct and in the case of model checking the state space can easily blow up. When abstracting, one has to make sure
that the system model retains the same behavior as the implementation for the properties of interest.
3.2.2 Requirement Properties and Specification Languages
Requirements on the system are commonly expressed in a temporal logic such as LTL (Linear Temporal Logic) [43] or
CTL (Computation Tree Logic) [10]. Requirement properties can be categorized as either liveness or safety properties
[29]. Characteristic for a safety property is that a violation is detectable using a finite system run. It can informally be
described using the sentence ―something bad will never happen‖ provided that the property holds in all reachable system
states. In contrast, a liveness property corresponds to the sentence ―something good will eventually happens‖. In order to
produce a counter example for a liveness property it is sometimes necessary to study infinite system runs. An example of
a liveness property is the one we used in Paper B and Paper D, expressed somewhat simplified: under the appropriate
premises, a given routing protocol will eventually find a route to a particular destination.
3.2.3 Applying the Method
Model Checking
There are two main advantages of model checking in comparison to deductive methods. The first one is that once the
system model has been constructed and the verification properties devised, the process is completely automatic and
outputs a ―yes‖ or ―no‖ answer. The other advantage is the possibility to generate error traces in case a property is not
fulfilled by the system. This makes it possible for the user to modify the model accordingly. The main disadvantage of
model checking is its limitation to finite state systems. It can, however, be used in hybrid infinite state verification
approaches where model checking is, for example, a component in a CEGAR (Counter-Example Guided Abstraction
Refinement) loop [12]. Furthermore, model checking of symbolically represented systems can be regarded as infinite state
since the original system may contain an unlimited element (such as continuous time). Using model checking, one can
check safety as well as liveness properties. Model checking algorithms work by exploring the state space whereby the
search stops at the first violation or when the complete execution tree has been examined. Methods can be divided into
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explicit state and symbolic model checking depending on if the individual states or groups (sets) of states are used to
represent the state space.
Deductive Verification
In deductive verification the goal is to prove that a conclusion, the property to be verified, can be drawn from a given set
of premises, the system description. This was previously a tedious manual process which has been speeded up with the
emergence of semi-automatic tools, so called theorem provers. One advantage of this method is that it can be used to
prove properties of infinite state systems, for example a protocol running in a network with an Unbounded number of
nodes. An invariant is an assertion that is true in all states of a system. A safety property, expressed as an invariant, can be
proven using mathematical induction. First it needs to be proven that the initial system configuration implies the assertion.
In the inductive step it is then checked whether all state transitions preserve the property, that is, if the assertion holds
before the transition it will also hold after it. Hence, the verification does not require an explicit state space search. This
avoids the state explosion problem at the cost of a more cumbersome proof process. The manual method was used by
Ogier [40] to make a proof of correctness for the TBRPF [39] protocol. For the discovery module he further presents a
proof that the neighbor information exchanged is sufficient for the functionality of the protocol.
3.2.4 The State Explosion Problem and Remedies
The state explosion problem in model checking refers to the situation in which the state space storage overhead grows
exponentially with the size of the model. This problem occurs because of the large number of possible interleaving
between processes in a reactive concurrent system. Verification may thereby fail simply because the available amount of
computer memory is limited. There have been a number of suggestions for coping with the state explosion, that is, to
make verification feasible for realistically sized systems. We list the major remedies below following the description by
Clarke et al. [9].Symbolic representation. Symbolic representation refers to the use of compact data structures for
representing state space. For example, by encoding the transition relations of a Kripke structure as a Binary Decision
Diagram (BDD) it is possible to save storage by exploiting the often inherent regularity of a hardware or software system.
Constraint system representation of continuous parameters such as clock ranges, which is done in UPPAAL, is another
example of a symbolic representation. In that case it would not even be possible to store all time points explicitly
regardless of the amount of available memory.Partial order reduction. Partial order reduction [24] is an optimization, for
example implemented in the SPIN tool. If a group of concurrently executing processes do not exchange any data
throughout their lifetime, then it does not make a difference for the end result if they are run one after the other or in
parallel. This makes verification simpler since the processes can be verified in isolation. However, once processes
cooperate, for example by message passing, which is certainly the case for protocol implementations, then the possible
interleaving of operation have to be taken into account when verifying the system. Partial order reduction is a way of
disregarding process interleavings that produce the same global state as some other interleaving. Note that the verification
property also needs to be taken into account since it might introduce additional data dependencies between processes.
Keeping as much as possible local to each modeled process can thus promote partial order reduction.
Compositional reasoning. This technique [2] involves decomposing the system into components which are verified
separately and in isolation from the rest. Global properties can then be inferred from the composition of the components.
If there are mutual dependencies between components one can still verify each component separately under the
assumption that the other components work as expected; assume-guarantee reasoning. There are both manual and
automatic approaches available for compositional reasoning.
4. Related Work
Routing below the IP layer for ad hoc networks was independently adapted by [1] using label switching which is
equivalent to the selectors. A similar project is [2] where the authors also aim at putting L2.5 routing logic inside the
(wireless) network interface card. For AODV, formal validations have been carried out by the Verinet group [19]. Using a
theorem prove and a SPIN model of AODV in a 2 node setup (with an AODV router environment), it is in fact a loop free
routing protocol. The Verinet group [23] have carried out formal validation of AODV [13] and identified a flaw that could
lead to loop formation. This was done using the HOL [24] theorem prover and a SPIN model of AODV in a two node
setup (with an AODV router environment). They have also suggested a modification and verified that, after this, the
protocol was loop free. Their approach verified the general case, but the methodology involves substantial user
interaction.
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5. Conclusions
This work is to our knowledge the first to study a range of topologies in order to determine where the limit actually is
when performing model checking on an ad hoc routing protocol. We have introduced the ad hoc routing protocol which
targets the common-case of network clouds with 10-15 nodes and a diameter of up to three hops. We believe that such
settings will be the most popular ones where ad hoc networks can and will be put into operation. More specially, in larger
settings and for IEEE 802.11 there are such severe degradations occurring under any ad hoc routing scheme that we do
not consider this to be a relevant use case that a routing protocol should try to address. When verifying both the data and
control aspects of the protocol using SPIN and when verifying the timing properties using UPPAAL the size of network,
i.e. the number of nodes involved, as well as the nature of the topological scenarios is limited due to state space storage
overhead. Even if parallel model checking approaches were used, our conclusion is that it is at this point not feasible to
provide a proof for topologies of any significant size by modeling the protocol directly. On the other hand, our study
enables us not only to analyze the modeling considerations that have to be imposed, but also provides us with a solid
starting point for the further work we intend to pursue in the direction of infinite-state verification of ad hoc routing
protocols.
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