This document provides an overview of Bluetooth technology. It describes Bluetooth as a wireless technology standard for short-range communication between devices like mobile phones, laptops, headphones, and other peripherals. It outlines Bluetooth's key features like operating in the 2.4GHz spectrum, using frequency hopping spread spectrum, and supporting ad-hoc network formation between up to 7 devices in a piconet. The document also summarizes Bluetooth's protocol stack and describes functions of layers like L2CAP, SDP, and security services.
- Bluetooth allows for connection of peripheral devices like headsets and joysticks through short-range wireless communication. It uses frequency-hopping spread spectrum in the 2.4GHz band for robust connectivity.
- Bluetooth devices can operate in a piconet with one master device and up to seven slave devices. Multiple piconets can interconnect to form a scatternet, allowing many devices to communicate in an area.
- The Bluetooth protocol stack includes layers for radio transmission, baseband control, link management, logical link/multiplexing, service discovery, and adoption of protocols like TCP/IP, OBEX, and telephony control.
Bluetooth is a wireless technology standard that allows short-range connections between devices like mobile phones, headphones, and laptops using radio waves in the 2.4 GHz spectrum. It uses frequency hopping spread spectrum technology and establishes piconets between one master device and up to seven slave devices to enable communication between connected devices. Bluetooth supports both synchronous and asynchronous connections and can be used to transfer data, voice, and interface with other wireless protocols like TCP/IP.
This document discusses Bluetooth and Mobile IP. It provides an overview of Bluetooth including its consortium, scenarios, specifications, and protocol architecture. It then discusses Mobile IP and the motivation for its development to allow for IP mobility as nodes change networks while maintaining ongoing connections and their IP address. The key requirement for Mobile IP is transparency, allowing mobile devices to keep their IP address and continue communication after changing networks.
Bluetooth is a wireless technology standard for exchanging data over short distances. It creates personal area networks (PANs) between devices like mobile phones, computers, and other electronic devices. Bluetooth operates in the unlicensed 2.4 GHz radio frequency band and uses frequency-hopping spread spectrum to avoid interference and jamming. It allows for both point-to-point and point-to-multipoint connections and can connect up to eight devices in a piconet. Common applications of Bluetooth include wireless headphones, connecting devices in cars, and wireless speakers.
This document discusses data networking and client-server communication. It covers distributed systems, network protocols, the OSI reference model, networking terminology like LANs and topologies, transmission networks, Ethernet, connecting to the internet, transport protocols like TCP and UDP, and IP addressing. Key concepts include layered network protocols, circuit-switched vs packet-switched networks, and connection-oriented vs connectionless protocols.
Consortium: Ericsson, Intel, IBM, Nokia, Toshiba…
Scenarios:
connection of peripheral devices
loudspeaker, joystick, headset
support of ad-hoc networking
small devices, low-cost
bridging of networks
e.g., GSM via mobile phone - Bluetooth - laptop
Simple, cheap, replacement of IrDA, low range, lower data rates, low-power
Worldwide operation: 2.4 GHz
Resistance to jamming and selective frequency fading:
FHSS over 79 channels (of 1MHz each), 1600hops/s
Coexistence of multiple piconets: like CDMA
Bluetooth is a wireless technology standard for exchanging data over short distances. It was created in 1994 initially to replace cables connecting devices like mobile phones, laptops, and peripherals. Bluetooth specifications allow for ad-hoc connections between up to eight devices within a range of around 30 feet. Devices are organized into piconets, with one device acting as the master to synchronize connections. Bluetooth aims to be a low-cost, low-power solution for connecting various consumer electronic devices and building personal area networks.
This document provides an overview of wireless communication technologies. It discusses wireless standards including Bluetooth, WiFi, and WiMAX. It describes key concepts such as wireless network architectures, frequency bands, modulation techniques, and multiple access methods. Generations of cellular networks are defined along with their associated data rates. Examples of wireless devices and services are given to illustrate real-world applications of these technologies.
- Bluetooth allows for connection of peripheral devices like headsets and joysticks through short-range wireless communication. It uses frequency-hopping spread spectrum in the 2.4GHz band for robust connectivity.
- Bluetooth devices can operate in a piconet with one master device and up to seven slave devices. Multiple piconets can interconnect to form a scatternet, allowing many devices to communicate in an area.
- The Bluetooth protocol stack includes layers for radio transmission, baseband control, link management, logical link/multiplexing, service discovery, and adoption of protocols like TCP/IP, OBEX, and telephony control.
Bluetooth is a wireless technology standard that allows short-range connections between devices like mobile phones, headphones, and laptops using radio waves in the 2.4 GHz spectrum. It uses frequency hopping spread spectrum technology and establishes piconets between one master device and up to seven slave devices to enable communication between connected devices. Bluetooth supports both synchronous and asynchronous connections and can be used to transfer data, voice, and interface with other wireless protocols like TCP/IP.
This document discusses Bluetooth and Mobile IP. It provides an overview of Bluetooth including its consortium, scenarios, specifications, and protocol architecture. It then discusses Mobile IP and the motivation for its development to allow for IP mobility as nodes change networks while maintaining ongoing connections and their IP address. The key requirement for Mobile IP is transparency, allowing mobile devices to keep their IP address and continue communication after changing networks.
Bluetooth is a wireless technology standard for exchanging data over short distances. It creates personal area networks (PANs) between devices like mobile phones, computers, and other electronic devices. Bluetooth operates in the unlicensed 2.4 GHz radio frequency band and uses frequency-hopping spread spectrum to avoid interference and jamming. It allows for both point-to-point and point-to-multipoint connections and can connect up to eight devices in a piconet. Common applications of Bluetooth include wireless headphones, connecting devices in cars, and wireless speakers.
This document discusses data networking and client-server communication. It covers distributed systems, network protocols, the OSI reference model, networking terminology like LANs and topologies, transmission networks, Ethernet, connecting to the internet, transport protocols like TCP and UDP, and IP addressing. Key concepts include layered network protocols, circuit-switched vs packet-switched networks, and connection-oriented vs connectionless protocols.
Consortium: Ericsson, Intel, IBM, Nokia, Toshiba…
Scenarios:
connection of peripheral devices
loudspeaker, joystick, headset
support of ad-hoc networking
small devices, low-cost
bridging of networks
e.g., GSM via mobile phone - Bluetooth - laptop
Simple, cheap, replacement of IrDA, low range, lower data rates, low-power
Worldwide operation: 2.4 GHz
Resistance to jamming and selective frequency fading:
FHSS over 79 channels (of 1MHz each), 1600hops/s
Coexistence of multiple piconets: like CDMA
Bluetooth is a wireless technology standard for exchanging data over short distances. It was created in 1994 initially to replace cables connecting devices like mobile phones, laptops, and peripherals. Bluetooth specifications allow for ad-hoc connections between up to eight devices within a range of around 30 feet. Devices are organized into piconets, with one device acting as the master to synchronize connections. Bluetooth aims to be a low-cost, low-power solution for connecting various consumer electronic devices and building personal area networks.
This document provides an overview of wireless communication technologies. It discusses wireless standards including Bluetooth, WiFi, and WiMAX. It describes key concepts such as wireless network architectures, frequency bands, modulation techniques, and multiple access methods. Generations of cellular networks are defined along with their associated data rates. Examples of wireless devices and services are given to illustrate real-world applications of these technologies.
This document provides an introduction to wireless technologies. It discusses wireless communication standards, computer networks, and reference models for network architecture. It covers frequencies and regulations, wireless communication technologies like signals, bandwidth, modulation, and propagation. It describes analog versus digital transmission and examples of each. It also summarizes key wireless systems over time like cellular generations, Bluetooth, Wi-Fi, WiMAX and wireless telephony. Finally, it discusses electromagnetic waves, the electromagnetic spectrum, and considerations around signal propagation and analysis.
LAN technologies allow computers to communicate over a shared medium. They use hardware addressing and MAC addresses to allow direct communication between any two hosts. Network interface cards connect computers to the physical network and use MAC addresses to identify devices. Common LAN technologies include Ethernet, Fast Ethernet, Gigabit Ethernet, and Wi-Fi, which use CSMA/CD protocols and packet framing to share the transmission medium.
HIPERLAN was a wireless network standard developed in Europe as an alternative to IEEE 802.11. It aimed to provide higher data rates and quality of service compared to early 802.11 standards. HIPERLAN Type 1 achieved data rates up to 2Mbps in the 1990s. HIPERLAN Type 2 was developed later to support connection-oriented networking at up to 54Mbps, with quality of service, security, and flexibility to connect to different wired networks. While prototypes existed, commercial products were still in development in the early 2000s as the standard competed with improving 802.11 variants.
Bluetooth is a wireless technology named after the 10th-century Danish king Harald Bluetooth. It allows for short-range wireless connections between devices like headsets, computers, and cell phones. Bluetooth devices operate on a shared frequency hopping spread spectrum that allows multiple devices to operate within range without interference. Devices can operate in a piconet, where one device acts as the master that controls communication, or scatternets, where devices participate in multiple overlapping piconets. Bluetooth provides security features like authentication and encryption to securely transmit data between connected devices.
King Harald Bluetooth unified warring Viking tribes in the 10th century. In the 21st century, a wireless Bluetooth network is named after him. Bluetooth allows for personal ad-hoc networks, cable replacement, and landline data/voice access through access points. It operates in the unlicensed 2.4GHz band using frequency hopping and supports data rates up to 1Mbps.
This document provides an overview of wireless personal area networks (WPANs), including Bluetooth, ZigBee, and Ultra-Wideband. It describes the key features and applications of each technology, how their protocols are structured, and how they compare to each other. Bluetooth supports data rates up to 2 Mbps over short ranges and is used in devices like phones, laptops, and printers. ZigBee focuses on low power consumption and supports thousands of nodes in a mesh network for uses like smart homes and buildings. Ultra-Wideband provides high data rates over short ranges and is used in applications like TVs, DVD players, and mobile devices.
This document provides an overview of computer networks, including their basic components, topologies, and technologies. It discusses network adapters, cables, wireless devices, common topologies like bus, star, and ring, and technologies such as Ethernet, Token Ring, ATM, and FDDI. It also covers ways to expand networks, including through the use of repeaters, hubs, bridges, switches, routers, and gateways, as well as remote access options and connectivity standards.
This document provides an overview of computer networks, including their basic components, topologies, and technologies. It discusses network adapters, cables, wireless devices, common topologies like bus, star, and ring. Network technologies covered include Ethernet, Token Ring, ATM, FDDI, and Frame Relay. The document also examines ways to expand networks, such as through repeaters, hubs, bridges, switches, routers, and various methods for remote access connectivity over telephone lines, ISDN, and ADSL.
The document provides information about line transmission and summarizes key details about the European E1 digital transmission format, the VMX0100 versatile multiplexer, and synchronous digital hierarchy (SDH). It describes that the E1 format reserves two channels for signaling and control, with time slot 0 for transmission management and time slot 16 for signaling. It then provides an introduction to the VMX0100 multiplexer, describing its features such as E1 and fractional E1 interfaces, voice ports, and data interfaces. The document discusses transmission mediums, cards, user interfaces, and applications of the VMX0100. It concludes with an introduction to SDH, describing its frame structure and advantages over the plesiochronous digital hierarchy such as support
Bluetooth is an open wireless technology standard for exchanging data over short distances. It was developed in 1994 initially to replace cables connecting devices like mobile phones and laptops. Bluetooth specifications define a protocol stack and use a radio technology called frequency-hopping spread spectrum in the 2.4GHz band. It allows for ad-hoc network topologies like piconets and scatternets. Profiles define how Bluetooth can be used in different applications. Bluetooth is now used in many consumer electronics products and future uses may include applications like home automation and location-based services.
The document discusses the Public Switched Telephone Network (PSTN) architecture and components. It describes how PSTN uses digital trunks between central office switches and analog lines from phones to the central office. It also discusses digitization of voice signals, the major components of PSTN including local loops, trunks, and switching offices.
Ethernet and Fast Ethernet standards define the physical implementation of local area networks using twisted pair cable and fiber optics. Ethernet uses CSMA/CD access method over coaxial cable or twisted pair up to 100 meters, while Fast Ethernet operates at 100 Mbps over twisted pair or fiber. Repeaters can extend the length of an Ethernet segment by regenerating the signal past the maximum segment distance.
A complete power point presentation to know how Public Switching Telephone Network works. Useful for those in the working field or for the ones who want to know more or submitting any project report..
This document discusses various topics related to WAN technologies including backup and restoration of Cisco IOS images, resolving hostnames, WAN connection types, encapsulation protocols, and an overview of technologies like ISDN, Frame Relay, ATM, and PPP. Specific configuration examples are provided for setting up PPP and CHAP authentication between two routers over a serial interface.
This document provides an overview of Orthogonal Frequency Division Multiplexing (OFDM). It discusses how OFDM works by dividing a high bit rate stream into several parallel low bit rate streams. It also explains how OFDM is robust against frequency selective fading due to multipath propagation. Key aspects of OFDM like guard intervals, cyclic prefixes, and bit loading are described to mitigate issues like intersymbol interference and intercarrier interference. Common OFDM applications like WiFi, WiMax, DAB, and HDTV are listed.
This document provides an overview of wireless LAN and Bluetooth technologies. It describes IEEE 802.11 standards for wireless LAN including the basic service set, extended service set, infrastructure and ad-hoc modes. It covers the physical layers, MAC protocols and services of 802.11. It also summarizes ATM and its extension to wireless networks, issues in the transition, proposed W-ATM architectures, advantages and disadvantages. Finally it defines Bluetooth technology, the protocol stack and unlicensed frequency band used.
Bluetooth Details
I run a knowledge sharing YouTube channel called (SILICON CHIPS TAMILAN). Please like, share, subscribe, and support me.
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https://siliconchipstamilan.blogspot.com/2022/12/what-is-outlook-mail.html
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The document discusses managing Cisco IOS images and configuring WAN connections. It covers topics such as copying flash images using TFTP, resolving hostnames, password recovery, and configuring encapsulation protocols like HDLC and PPP. Specific configuration examples are provided for setting the CHAP authentication protocol on serial interfaces between two routers.
This document provides an introduction to wireless technologies. It discusses wireless communication standards, computer networks, and reference models for network architecture. It covers frequencies and regulations, wireless communication technologies like signals, bandwidth, modulation, and propagation. It describes analog versus digital transmission and examples of each. It also summarizes key wireless systems over time like cellular generations, Bluetooth, Wi-Fi, WiMAX and wireless telephony. Finally, it discusses electromagnetic waves, the electromagnetic spectrum, and considerations around signal propagation and analysis.
LAN technologies allow computers to communicate over a shared medium. They use hardware addressing and MAC addresses to allow direct communication between any two hosts. Network interface cards connect computers to the physical network and use MAC addresses to identify devices. Common LAN technologies include Ethernet, Fast Ethernet, Gigabit Ethernet, and Wi-Fi, which use CSMA/CD protocols and packet framing to share the transmission medium.
HIPERLAN was a wireless network standard developed in Europe as an alternative to IEEE 802.11. It aimed to provide higher data rates and quality of service compared to early 802.11 standards. HIPERLAN Type 1 achieved data rates up to 2Mbps in the 1990s. HIPERLAN Type 2 was developed later to support connection-oriented networking at up to 54Mbps, with quality of service, security, and flexibility to connect to different wired networks. While prototypes existed, commercial products were still in development in the early 2000s as the standard competed with improving 802.11 variants.
Bluetooth is a wireless technology named after the 10th-century Danish king Harald Bluetooth. It allows for short-range wireless connections between devices like headsets, computers, and cell phones. Bluetooth devices operate on a shared frequency hopping spread spectrum that allows multiple devices to operate within range without interference. Devices can operate in a piconet, where one device acts as the master that controls communication, or scatternets, where devices participate in multiple overlapping piconets. Bluetooth provides security features like authentication and encryption to securely transmit data between connected devices.
King Harald Bluetooth unified warring Viking tribes in the 10th century. In the 21st century, a wireless Bluetooth network is named after him. Bluetooth allows for personal ad-hoc networks, cable replacement, and landline data/voice access through access points. It operates in the unlicensed 2.4GHz band using frequency hopping and supports data rates up to 1Mbps.
This document provides an overview of wireless personal area networks (WPANs), including Bluetooth, ZigBee, and Ultra-Wideband. It describes the key features and applications of each technology, how their protocols are structured, and how they compare to each other. Bluetooth supports data rates up to 2 Mbps over short ranges and is used in devices like phones, laptops, and printers. ZigBee focuses on low power consumption and supports thousands of nodes in a mesh network for uses like smart homes and buildings. Ultra-Wideband provides high data rates over short ranges and is used in applications like TVs, DVD players, and mobile devices.
This document provides an overview of computer networks, including their basic components, topologies, and technologies. It discusses network adapters, cables, wireless devices, common topologies like bus, star, and ring, and technologies such as Ethernet, Token Ring, ATM, and FDDI. It also covers ways to expand networks, including through the use of repeaters, hubs, bridges, switches, routers, and gateways, as well as remote access options and connectivity standards.
This document provides an overview of computer networks, including their basic components, topologies, and technologies. It discusses network adapters, cables, wireless devices, common topologies like bus, star, and ring. Network technologies covered include Ethernet, Token Ring, ATM, FDDI, and Frame Relay. The document also examines ways to expand networks, such as through repeaters, hubs, bridges, switches, routers, and various methods for remote access connectivity over telephone lines, ISDN, and ADSL.
The document provides information about line transmission and summarizes key details about the European E1 digital transmission format, the VMX0100 versatile multiplexer, and synchronous digital hierarchy (SDH). It describes that the E1 format reserves two channels for signaling and control, with time slot 0 for transmission management and time slot 16 for signaling. It then provides an introduction to the VMX0100 multiplexer, describing its features such as E1 and fractional E1 interfaces, voice ports, and data interfaces. The document discusses transmission mediums, cards, user interfaces, and applications of the VMX0100. It concludes with an introduction to SDH, describing its frame structure and advantages over the plesiochronous digital hierarchy such as support
Bluetooth is an open wireless technology standard for exchanging data over short distances. It was developed in 1994 initially to replace cables connecting devices like mobile phones and laptops. Bluetooth specifications define a protocol stack and use a radio technology called frequency-hopping spread spectrum in the 2.4GHz band. It allows for ad-hoc network topologies like piconets and scatternets. Profiles define how Bluetooth can be used in different applications. Bluetooth is now used in many consumer electronics products and future uses may include applications like home automation and location-based services.
The document discusses the Public Switched Telephone Network (PSTN) architecture and components. It describes how PSTN uses digital trunks between central office switches and analog lines from phones to the central office. It also discusses digitization of voice signals, the major components of PSTN including local loops, trunks, and switching offices.
Ethernet and Fast Ethernet standards define the physical implementation of local area networks using twisted pair cable and fiber optics. Ethernet uses CSMA/CD access method over coaxial cable or twisted pair up to 100 meters, while Fast Ethernet operates at 100 Mbps over twisted pair or fiber. Repeaters can extend the length of an Ethernet segment by regenerating the signal past the maximum segment distance.
A complete power point presentation to know how Public Switching Telephone Network works. Useful for those in the working field or for the ones who want to know more or submitting any project report..
This document discusses various topics related to WAN technologies including backup and restoration of Cisco IOS images, resolving hostnames, WAN connection types, encapsulation protocols, and an overview of technologies like ISDN, Frame Relay, ATM, and PPP. Specific configuration examples are provided for setting up PPP and CHAP authentication between two routers over a serial interface.
This document provides an overview of Orthogonal Frequency Division Multiplexing (OFDM). It discusses how OFDM works by dividing a high bit rate stream into several parallel low bit rate streams. It also explains how OFDM is robust against frequency selective fading due to multipath propagation. Key aspects of OFDM like guard intervals, cyclic prefixes, and bit loading are described to mitigate issues like intersymbol interference and intercarrier interference. Common OFDM applications like WiFi, WiMax, DAB, and HDTV are listed.
This document provides an overview of wireless LAN and Bluetooth technologies. It describes IEEE 802.11 standards for wireless LAN including the basic service set, extended service set, infrastructure and ad-hoc modes. It covers the physical layers, MAC protocols and services of 802.11. It also summarizes ATM and its extension to wireless networks, issues in the transition, proposed W-ATM architectures, advantages and disadvantages. Finally it defines Bluetooth technology, the protocol stack and unlicensed frequency band used.
Bluetooth Details
I run a knowledge sharing YouTube channel called (SILICON CHIPS TAMILAN). Please like, share, subscribe, and support me.
YouTube Link : https://www.youtube.com/channel/UCenZp9ho_PP0K5iYrdocvrw
Notes Link Below attached
https://siliconchipstamilan.blogspot.com/2022/12/what-is-outlook-mail.html
My YouTube chancel Link
https://www.youtube.com/channel/UCenZp9ho_PP0K5iYrdocvrw
My Facebook page Link
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The document discusses managing Cisco IOS images and configuring WAN connections. It covers topics such as copying flash images using TFTP, resolving hostnames, password recovery, and configuring encapsulation protocols like HDLC and PPP. Specific configuration examples are provided for setting the CHAP authentication protocol on serial interfaces between two routers.
2. Wireless Networks Spring 2005
Bluetooth
Consortium: Ericsson, Intel, IBM, Nokia, Toshiba…
Scenarios:
o connection of peripheral devices
• loudspeaker, joystick, headset
o support of ad-hoc networking
• small devices, low-cost
o bridging of networks
• e.g., GSM via mobile phone - Bluetooth - laptop
Simple, cheap, replacement of IrDA, low range, lower data rates,
low-power
o Worldwide operation: 2.4 GHz
o Resistance to jamming and selective frequency fading:
• FHSS over 79 channels (of 1MHz each), 1600hops/s
o Coexistence of multiple piconets: like CDMA
o Links: synchronous connections and asynchronous connectionless
o Interoperability: protocol stack supporting TCP/IP, OBEX, SDP
o Range: 10 meters, can be extended to 100 meters
Documentation: over 1000 pages specification: www.bluetooth.com
3. Wireless Networks Spring 2005
Bluetooth Application Areas
Data and voice access points
o Real-time voice and data transmissions
Cable replacement
o Eliminates need for numerous cable attachments for
connection
Low cost < $5
Ad hoc networking
o Device with Bluetooth radio can establish connection with
another when in range
4. Wireless Networks Spring 2005
Protocol Architecture
Bluetooth is a layered protocol architecture
o Core protocols
o Cable replacement and telephony control protocols
o Adopted protocols
Core protocols
o Radio
o Baseband
o Link manager protocol (LMP)
o Logical link control and adaptation protocol (L2CAP)
o Service discovery protocol (SDP)
5. Wireless Networks Spring 2005
Protocol Architecture
Cable replacement protocol
o RFCOMM
Telephony control protocol
o Telephony control specification – binary (TCS BIN)
Adopted protocols
o PPP
o TCP/UDP/IP
o OBEX
o WAE/WAP
6. Wireless Networks Spring 2005
Protocol Architecture
BT Radio (2.4 GHZ Freq. Band):
Modulation: Gaussian Frequency Shift Keying
Baseband: FH-SS (79 carriers), CDMA (hopping
sequence from the node MAC address)
Audio: interfaces directly with the baseband. Each
voice connection is over a 64Kbps SCO link. The
voice coding scheme is the Continuous Variable
Slope Delta (CVSD)
Link Manager Protocol (LMP): link setup and
control, authentication and encryption
Host Controller Interface: provides a uniform
method of access to the baseband, control
registers, etc through USB, PCI, or UART
Logical Link Control and Adaptation Layer (L2CAP):
higher protocols multiplexing, packet
segmentation/reassembly, QoS
Service Discover Protocol (SDP): protocol of
locating services provided by a Bluetooth device
Telephony Control Specification (TCS): defines the
call control signaling for the establishment of
speech and data calls between Bluetooth devices
RFCOMM: provides emulation of serial links
(RS232). Upto 60 connections
HCI
Bluetooth Radio
Baseband
Audio Link Manager (LMP)
L2CAP
RFCOMM TCS SDP
TCP/UDP
PPP
AT
Commands
OBEX
Application
OBEX: OBject EXchange (e.g., vCard)
7. Wireless Networks Spring 2005
Usage Models
File transfer
Internet bridge
LAN access
Synchronization
Three-in-one phone
Headset
8. Wireless Networks Spring 2005
Piconets and Scatternets
Piconet
o Basic unit of Bluetooth networking
o Master and one to seven slave devices
o Master determines channel and phase
Scatternet
o Device in one piconet may exist as master or slave in
another piconet
o Allows many devices to share same area
o Makes efficient use of bandwidth
10. Wireless Networks Spring 2005
Network Topology
Piconet = set of Bluetooth nodes synchronized to a master node
o The piconet hopping sequence is derived from the master MAC address
(BD_ADDR IEEE802 48 bits compatible address)
Scatternet = set of piconet
Master-Slaves can switch roles
A node can only be master of one piconet. Why?
Piconet 1
Master
Master
Piconet 2
Scatternet
Slave
11. Wireless Networks Spring 2005
Scatternets
piconets
Each piconet has one master and up to 7 slaves
Master determines hopping sequence, slaves have to synchronize
Participation in a piconet = synchronization to hopping sequence
Communication between piconets = devices jumping back and forth
between the piconets
12. Wireless Networks Spring 2005
Radio Specification
Classes of transmitters
o Class 1: Outputs 100 mW for maximum range
• Power control mandatory
• Provides greatest distance
o Class 2: Outputs 2.4 mW at maximum
• Power control optional
o Class 3: Nominal output is 1 mW
• Lowest power
Frequency Hopping in Bluetooth
o Provides resistance to interference and multipath effects
o Provides a form of multiple access among co-located
devices in different piconets
13. Wireless Networks Spring 2005
Frequency Hopping
Total bandwidth divided into 1MHz physical
channels
FH occurs by jumping from one channel to
another in pseudorandom sequence
Hopping sequence shared with all devices on
piconet
Piconet access:
o Bluetooth devices use time division duplex (TDD)
o Access technique is TDMA
o FH-TDD-TDMA
15. Wireless Networks Spring 2005
Physical Links
Synchronous connection oriented (SCO)
o Allocates fixed bandwidth between point-to-point
connection of master and slave
o Master maintains link using reserved slots
o Master can support three simultaneous links
Asynchronous connectionless (ACL)
o Point-to-multipoint link between master and all slaves
o Only single ACL link can exist
16. Wireless Networks Spring 2005
Bluetooth Packet Fields
Access code – used for timing
synchronization, offset compensation,
paging, and inquiry
Header – used to identify packet type and
carry protocol control information
Payload – contains user voice or data and
payload header, if present
17. Wireless Networks Spring 2005
Bluetooth Piconet MAC
Each node has a Bluetooth Device Address (BD_ADDR). The master
BD_ADDR determines the sequence of frequency hops
Types of connections:
Synchronous Connection-Oriented link (SCO) (symmetrical, circuit switched, point-to-point)
Asynchronous Connectionless Link (ACL): (packet switched, point-to-multipoint, master-
polls)
Packet Format:
o Access code: synchronization, when piconet active derived from master
o Packet header (for ACL): 1/3-FEC, MAC address (1 master, 7 slaves), link type,
alternating bit ARQ/SEQ, checksum
f(k) f(k+1) f(k+2) f(k+3) f(k+4) f(k+4) f(k+4) f(k+7)
Master
Slave 1
Slave 2
bits
access code packet header payload
72 54 0-2745 bits
MAC address type flow ARQN SEQN HEC
3 4 1 1 1 8
18. Wireless Networks Spring 2005
Types of Access Codes
Channel access code (CAC) – identifies a
piconet
Device access code (DAC) – used for
paging and subsequent responses
Inquiry access code (IAC) – used for
inquiry purposes
Preamble+sync+trailer
19. Wireless Networks Spring 2005
Packet Header Fields
AM_ADDR – contains “active mode” address of
one of the slaves
Type – identifies type of packet
o ACL: Data Medium (DM) or Data High (DH), with
different slot lengths (DM1, DM3, DM5, DH1, DH3, DH5)
o SCO: Data Voice (DV) and High-quality voice (HV)
Flow – 1-bit flow control
ARQN – 1-bit acknowledgment
SEQN – 1-bit sequential numbering schemes
Header error control (HEC) – 8-bit error detection
code
20. Wireless Networks Spring 2005
Payload Format
Payload header
o L_CH field – identifies logical channel
o Flow field – used to control flow at L2CAP level
o Length field – number of bytes of data
Payload body – contains user data
CRC – 16-bit CRC code
21. Wireless Networks Spring 2005
Error Correction Schemes
1/3 rate FEC (forward error correction)
o Used on 18-bit packet header, voice field in
HV1 packet
2/3 rate FEC
o Used in DM packets, data fields of DV packet,
FHS packet and HV2 packet
ARQ
o Used with DM and DH packets
22. Wireless Networks Spring 2005
ARQ Scheme Elements
Error detection – destination detects errors,
discards packets
Positive acknowledgment – destination returns
positive acknowledgment
Retransmission after timeout – source retransmits
if packet unacknowledged
Negative acknowledgment and retransmission –
destination returns negative acknowledgement for
packets with errors, source retransmits
23. Wireless Networks Spring 2005
Types of packets
SCO packets: Do not have a CRC (except for the data part of DV)
and are never retransmitted. Intended for High-quality Voice
(HV).
ACL packets: Data Medium-rate (DM) and Data High-rate (DH)
Type Payload
(bytes)
FEC CRC max-rate kbps
HV1 10 1/3 No 64
HV2 20 2/3 No 64
HV3 30 No No 64
DV 10+(1-10)D 2/3D Yes D 64+57.6D
Type Payload
(bytes)
FEC CRC Symm.
max-rate kbps
Asymm.
max-rate (DL/UL)
DM1 0-17 2/3 Yes 108.8 108.8/108.9
DM3 0-121 2/3 Yes 258.1 387.2/54.4
DM5 0-224 2/3 Yes 286.7 477.8/36.3
DH1 0-27 No Yes 172.8 172.8/172.8
DH3 0-183 No Yes 390.4 585.6/86.4
DH5 0-339 No Yes 433.9 723.2/185.6
24. Wireless Networks Spring 2005
Channel Control
Major states
o Standby – default state
o Connection – device connected
Interim substates for adding new slaves
o Page – device issued a page (used by master)
o Page scan – device is listening for a page
o Master response – master receives a page response from
slave
o Slave response – slave responds to a page from master
o Inquiry – device has issued an inquiry for identity of
devices within range
o Inquiry scan – device is listening for an inquiry
o Inquiry response – device receives an inquiry response
26. Wireless Networks Spring 2005
Inquiry Procedure
Potential master identifies devices in range that
wish to participate
o Transmits ID packet with inquiry access code (IAC)
o Occurs in Inquiry state
Device receives inquiry
o Enter Inquiry Response state
o Returns FHS (Frequency Hop Synchrnonization) packet
with address and timing information
o Moves to page scan state
27. Wireless Networks Spring 2005
Inquiry Procedure Details
Goal: aims at discovering other neighboring devices
Inquiring node:
o Sends an inquiry message (packet with only the access code: General
Inquiry Access Code: GIAC or Dedicated IAC: DIAC). This message is sent
over a subset of all possible frequencies.
o The inquiry frequencies are divided into two hopping sets of 16 frequencies
each.
o In inquiry state the node will send upto NINQUIRY sequences on one set of 16
frequencies before switching to the other set of 16 frequencies. Upto 3
switches can be executed. Thus the inquiry may last upto 10.24 seconds.
To be discovered node:
o Enters an inquiry_scan mode
o When hearing the inquiry_message (and after a backoff procedure) enter
an inquiry_response mode: send a Frequency Hop Sync (FHS) packet
(BD_ADDR, native clock)
After discovering the neighbors and collecting information on their
address and clock, the inquiring node can start a page routine to setup
a piconet
28. Wireless Networks Spring 2005
Page Procedure
Master uses devices address to calculate a
page frequency-hopping sequence
Master pages with ID packet and device
access code (DAC) of specific slave
Slave responds with DAC ID packet
Master responds with its FHS packet
Slave confirms receipt with DAC ID
Slaves moves to Connection state
29. Wireless Networks Spring 2005
Page Procedure Details
Goal: e.g., setup a piconet after an inquiry
Paging node (master):
o Sends a page message (i.e., packet with only Device
Access Code of paged node) over 32 frequency hops
(from DAC and split into 2*16 freq.)
o Repeated until a response is received
o When a response is received send a FHS message to
allow the paged node to synchronize
Paged node (slave):
o Listens on its hopping sequence
o When receiving a page message, send a page_response
and wait for the FHS of the pager
30. Wireless Networks Spring 2005
Slave Connection State Modes
Active – participates in piconet
o Listens, transmits and receives packets
Sniff – only listens on specified slots
Hold – does not support ACL packets
o Reduced power status
o May still participate in SCO exchanges
Park – does not participate on piconet
o Still retained as part of piconet
31. Wireless Networks Spring 2005
States of a Bluetooth Device
STANDBY
inquiry page
connected
transmit
PARK HOLD SNIFF
unconnected
connecting
active
low power
BT device addressing:
• BD_ADDR (48 bits)
• AM_ADDR ( 3bits): ACTIVE, HOLD, or SNIFF
• PM_ADDR (8 bits): PARK Mode address (exchanged with the AM_ADDR when entering PARK mode)
• AR_ADDR (8 bits): not unique used to come back from PARK to ACTIVE state
ACTIVE (connected/transmit): the device is uniquely identified by a 3bits AM_ADDR and
is fully participating
SNIFF state: participates in the piconet only within the SNIFF interval
HOLD state: keeps only the SCO links
PARK state (low-power): releases AM_ADDR but stays synchronized with master
32. Wireless Networks Spring 2005
Bluetooth Audio
Voice encoding schemes:
o Pulse code modulation (PCM)
o Continuously variable slope delta (CVSD)
modulation
Choice of scheme made by link manager
o Negotiates most appropriate scheme for
application
33. Wireless Networks Spring 2005
Bluetooth Link Security
Elements:
o Authentication – verify claimed identity
o Encryption – privacy
o Key management and usage
Security algorithm parameters:
o Unit address
o Secret authentication key (128 bits key)
o Secret privacy key (4-128 bits secret key)
o Random number
34. Wireless Networks Spring 2005
Link Management
Manages master-slave radio link
Security Service: authentication,
encryption, and key distribution
Clock synchronization
Exchange station capability information
Mode management:
o switch master/slave role
o change hold, sniff, park modes
o QoS
35. Wireless Networks Spring 2005
L2CAP
Provides a link-layer protocol between entities
with a number of services
Relies on lower layer for flow and error control
Makes use of ACL links, does not support SCO
links
Provides two alternative services to upper-layer
protocols
o Connectionless service
o Connection-oriented service: A QoS flow specification is
assigned in each direction
Exchange of signaling messages to establish and
configure connection parameters
38. Wireless Networks Spring 2005
Motivation for Mobile IP
Routing
o based on IP destination address, network prefix (e.g.
129.13.42) determines physical subnet
o change of physical subnet implies change of IP address to have
a topological correct address (standard IP) or needs special
entries in the routing tables
Specific routes to end-systems?
o change of all routing table entries to forward packets to the
right destination
o does not scale with the number of mobile hosts and frequent
changes in the location, security problems
Changing the IP-address?
o adjust the host IP address depending on the current location
o almost impossible to find a mobile system, DNS updates take
too much time
o TCP connections break, security problems
39. Wireless Networks Spring 2005
Mobile IP Requirements
Transparency
o mobile end-systems keep their IP address
o continuation of communication after interruption of link
possible
o point of connection to the fixed network can be changed
Compatibility
o support of the same layer 2 protocols as IP
o no changes to current end-systems and routers required
o mobile end-systems can communicate with fixed systems
Security
o authentication of all registration messages
Efficiency and scalability
o only little additional messages to the mobile system required
(connection typically via a low bandwidth radio link)
o world-wide support of a large number of mobile systems in the
whole Internet
40. Wireless Networks Spring 2005
Terminology
Mobile Node (MN)
o system (node) that can change the point of connection
to the network without changing its IP address
Home Agent (HA)
o system in the home network of the MN, typically a router
o registers the location of the MN, tunnels IP datagrams to the COA
Foreign Agent (FA)
o system in the current foreign network of the MN, typically a
router
o forwards the tunneled datagrams to the MN, typically also the
default router for the MN
Care-of Address (COA)
o address of the current tunnel end-point for the MN (at FA or MN)
o actual location of the MN from an IP point of view
o can be chosen, e.g., via DHCP
Correspondent Node (CN)
o communication partner
41. Wireless Networks Spring 2005
Example network
mobile end-system
Internet
router
router
router
end-system
FA
HA
MN
home network
foreign
network
(physical home network
for the MN)
(current physical network
for the MN)
CN
42. Wireless Networks Spring 2005
Data transfer to the mobile
Internet
sender
FA
HA
MN
home network
foreign
network
receiver
1
2
3
1. Sender sends to the IP address of MN,
HA intercepts packet (proxy ARP)
2. HA tunnels packet to COA, here FA,
by encapsulation
3. FA forwards the packet
to the MN
CN
43. Wireless Networks Spring 2005
Data transfer from the mobile
Internet
receiver
FA
HA
MN
home network
foreign
network
sender
1
1. Sender sends to the IP address
of the receiver as usual,
FA works as default router
CN
44. Wireless Networks Spring 2005
Overview
CN
router
HA
router
FA
Internet
router
1.
2.
3.
home
network
MN
foreign
network
4.
CN
router
HA
router
FA
Internet
router
home
network
MN
foreign
network
COA
45. Wireless Networks Spring 2005
Network integration
Agent Advertisement
o HA and FA periodically send advertisement messages into
their physical subnets
o MN listens to these messages and detects, if it is in the home
or a foreign network (standard case for home network)
o MN reads a COA from the FA advertisement messages
Registration (always limited lifetime!)
o MN signals COA to the HA via the FA, HA acknowledges via
FA to MN
o these actions have to be secured by authentication
Advertisement
o HA advertises the IP address of the MN (as for fixed
systems), i.e. standard routing information
o routers adjust their entries, these are stable for a longer time
(HA responsible for a MN over a longer period of time)
o packets to the MN are sent to the HA,
o independent of changes in COA/FA
46. Wireless Networks Spring 2005
Agent advertisement
preference level 1
router address 1
#addresses
type
addr. size lifetime
checksum
COA 1
COA 2
type sequence number
length
0 7 8 15 16 31
24
23
code
preference level 2
router address 2
. . .
registration lifetime
. . .
R B H F M G V reserved
ICMP-Type = 0; Code = 0/16; Extension Type = 16
TTL = 1 Dest-Adr = 224.0.0.1 (multicast on link) or 255.255.255.255 (broadcast)
R: registration required
B: busy
H: home agent
F: foreign agent
M: minimal encapsulation
G: generic encapsulation
V: header compression
47. Wireless Networks Spring 2005
Registration
t
MN HA
t
MN FA HA
Goal: inform the home agent of current location of MN (COA-FA or co-located COA)
Registration expires automatically (lifetime)
Uses UDP port 434
48. Wireless Networks Spring 2005
Mobile IP registration request
home agent
home address
type lifetime
0 7 8 15 16 31
24
23
rsv
identification
COA
extensions . . .
S B DMGV
UDP packet on port 343
Type = 1 for registration request
S: retain prior mobility bindings
B: forward broadcast packets
D: co-located address=> MN decapsulates packets
49. Wireless Networks Spring 2005
Encapsulation
original IP header original data
new data
new IP header
outer header inner header original data
50. Wireless Networks Spring 2005
Encapsulation I
Encapsulation of one packet into another as payload
o e.g. IPv6 in IPv4 (6Bone), Multicast in Unicast (Mbone)
o here: e.g. IP-in-IP-encapsulation, minimal encapsulation or
GRE (Generic Record Encapsulation)
IP-in-IP-encapsulation (mandatory in RFC 2003)
o tunnel between HA and COA
Care-of address COA
IP address of HA
TTL
IP identification
IP-in-IP IP checksum
flags fragment offset
length
TOS
ver. IHL
IP address of MN
IP address of CN
TTL
IP identification
lay. 4 prot. IP checksum
flags fragment offset
length
TOS
ver. IHL
TCP/UDP/ ... payload
51. Wireless Networks Spring 2005
Encapsulation II
Minimal encapsulation (optional) [RFC2004]
o avoids repetition of identical fields
o e.g. TTL, IHL, version, TOS
o only applicable for unfragmented packets, no space left
for fragment identification
care-of address COA
IP address of HA
TTL
IP identification
min. encap. IP checksum
flags fragment offset
length
TOS
ver. IHL
IP address of MN
original sender IP address (if S=1)
S
lay. 4 protoc. IP checksum
TCP/UDP/ ... payload
reserved
52. Wireless Networks Spring 2005
Optimization of packet forwarding
Triangular Routing
o sender sends all packets via HA to MN
o higher latency and network load
“Solutions”
o sender learns the current location of MN
o direct tunneling to this location
o HA informs a sender about the location of MN
o big security problems!
Change of FA
o packets on-the-fly during the change can be lost
o new FA informs old FA to avoid packet loss, old FA now
forwards remaining packets to new FA
o this information also enables the old FA to release
resources for the MN
53. Wireless Networks Spring 2005
Change of foreign agent
CN HA FAold FAnew MN
t
request
update
ACK
data data
MN changes
location
registration
update
ACK
data
data data
warning
update
ACK
data
data
registration
54. Wireless Networks Spring 2005
Reverse tunneling (RFC 2344)
Internet
receiver
FA
HA
MN
home network
foreign
network
sender
3
2
1
1. MN sends to FA
2. FA tunnels packets to HA
by encapsulation
3. HA forwards the packet to the
receiver (standard case)
CN
55. Wireless Networks Spring 2005
Mobile IP with reverse tunneling
Routers accept often only “topological correct“ addresses
(firewall)
o a packet from the MN encapsulated by the FA is now
topological correct
o furthermore multicast and TTL problems solved (TTL in the
home network correct, but MN is to far away from the receiver)
Reverse tunneling does not solve
o problems with firewalls, the reverse tunnel can be abused to
circumvent security mechanisms (tunnel hijacking)
o optimization of data paths, i.e. packets will be forwarded
through the tunnel via the HA to a sender (double triangular
routing)
The new standard is backwards compatible
o the extensions can be implemented easily and cooperate with
current implementations without these extensions
56. Wireless Networks Spring 2005
Mobile IP and IPv6
security is integrated and not an add-on, authentication of
registration is included
COA can be assigned via auto-configuration (DHCPv6 is one
candidate), every node has address autoconfiguration
no need for a separate FA, all routers perform router
advertisement which can be used instead of the special
agent advertisement
MN can signal a sender directly the COA, sending via HA not
needed in this case (automatic path optimization)
“soft” hand-over, i.e. without packet loss, between two
subnets is supported
o MN sends the new COA to its old router
o the old router encapsulates all incoming packets for the MN and
forwards them to the new COA
o authentication is always granted
57. Wireless Networks Spring 2005
Problems with Mobile IP
Security
o authentication with FA problematic, for the FA typically belongs
to another organization
o no protocol for key management and key distribution has been
standardized in the Internet
o patent and export restrictions
Firewalls
o typically mobile IP cannot be used together with firewalls,
special set-ups are needed (such as reverse tunneling)
QoS
o many new reservations in case of RSVP
o tunneling makes it hard to give a flow of packets a special
treatment needed for the QoS
Security, firewalls, QoS etc. are topics of current research
and discussions!