Frame Relay is a WAN technology that uses virtual circuits (VCs) to connect multiple remote sites over a single serial interface on a router in a more cost-effective way than leased lines. There are two types of VCs - permanent VCs that remain active and switched VCs that are dynamically created. Each VC is identified by a unique data-link connection identifier (DLCI). Frame Relay uses these VCs to create logical connections between devices on a physical circuit.
These slides cover a topic on X.25, Frame relay and ATM in Data Communication. All the slides are explained in a very simple manner. It is useful for engineering students & also for the candidates who want to master data communication & computer networking.
These slides cover a topic on X.25, Frame relay and ATM in Data Communication. All the slides are explained in a very simple manner. It is useful for engineering students & also for the candidates who want to master data communication & computer networking.
The IEEE 802 is a family of IEEE standards dealing with Local Area Networks and Metropolitan Area Networks. The IEEE 802 family of standards is maintained by the IEEE 802 LAN/MAN Standards Committee (LMSC).
The most widely used standards are for the Bridging and Virtual Bridged LANs (802.1), Ethernet family (802.3), Token Ring (802.5) and Wireless LAN (802.11).
Although the OSI reference model is universally recognized, the historical and technical open standard of the Internet is Transmission Control Protocol / Internet Protocol (TCP/IP).
The TCP/IP reference model and the TCP/IP protocol stack make data communication possible between any two computers, anywhere in the world, at nearly the speed of light.
TCP/IP have 5 layers, whereas OSI model have 7 layers in its Model. TCP/IP is known for the secured connection and comunication. I have explained all functions and definitions of layers in TCP/IP Model
These slides cover a topic on Spread spectrum in Data Communication. All the slides are explained in a very simple manner. It is useful for engineering students & also for the candidates who want to master data communication & computer networking.
Frame Relay is a high-performance WAN protocol that operates at the physical and data link layers of
the OSI reference model. Frame Relay originally was designed for use across Integrated Services Digital
Network (ISDN) interfaces. Today, it is used over a variety of other network interfaces as well.
Frame relay is a type of WAN connection use to connect one site to many remote sites through a single
physical circuit; this operation makes it easy to construct reliable and inexpensive networks.
The IEEE 802 is a family of IEEE standards dealing with Local Area Networks and Metropolitan Area Networks. The IEEE 802 family of standards is maintained by the IEEE 802 LAN/MAN Standards Committee (LMSC).
The most widely used standards are for the Bridging and Virtual Bridged LANs (802.1), Ethernet family (802.3), Token Ring (802.5) and Wireless LAN (802.11).
Although the OSI reference model is universally recognized, the historical and technical open standard of the Internet is Transmission Control Protocol / Internet Protocol (TCP/IP).
The TCP/IP reference model and the TCP/IP protocol stack make data communication possible between any two computers, anywhere in the world, at nearly the speed of light.
TCP/IP have 5 layers, whereas OSI model have 7 layers in its Model. TCP/IP is known for the secured connection and comunication. I have explained all functions and definitions of layers in TCP/IP Model
These slides cover a topic on Spread spectrum in Data Communication. All the slides are explained in a very simple manner. It is useful for engineering students & also for the candidates who want to master data communication & computer networking.
Frame Relay is a high-performance WAN protocol that operates at the physical and data link layers of
the OSI reference model. Frame Relay originally was designed for use across Integrated Services Digital
Network (ISDN) interfaces. Today, it is used over a variety of other network interfaces as well.
Frame relay is a type of WAN connection use to connect one site to many remote sites through a single
physical circuit; this operation makes it easy to construct reliable and inexpensive networks.
A WAN (Wide Area Network) is a network that covers a broad area (i.e., any telecommunications
network that links across metropolitan, regional, national or international boundaries) using leased
telecommunication lines. Business and government entities utilize WANs to relay data among
employees, clients, buyers, and suppliers from various geographical locations. In essence, this mode of
telecommunication allows a business to effectively carry out its daily function regardless of location. The
Internet can be considered a WAN as well, and is used by businesses, governments, organizations, and
individuals for almost any purpose imaginable.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
2. Frame Relay is a scalable WAN solution that is often used
as an alternative to leased lines when leased lines prove to
be cost unaffordable. With Frame Relay, you can have a
single serial interface on a router connecting into multiple
remote sites through virtual circuits.
3. Virtual Circuits (VCs)
A VC is a logical connection between two devices; therefore, many of
these VCs can exist on the same physical connection. The advantage
that VCs have over leased lines is that they can provide full connectivity
at a much lower price. VCs are also full-duplex: you can simultaneously
send and receive on the same VC.
There are two types of VCs: permanent VCs (PVCs) and switched or
semipermanent VCs (SVCs).
PVC is similar to a leased line: it is configured up front by the carrier
and remains up as long as there is a physical circuit path from the
source to the destination.
SVC are similar to telephone circuit-switched connections: whenever
you need to send data to a connection, an SVC is dynamically built and
then torn down once your data has been sent.
Disadvantage of PVCs is that they require a lot of manual configuration
up front to establish the VC. Another disadvantage is that they aren't
very flexible: if the PVC fails, there is no dynamic rebuilding of the PVC
around the failure.
4. LMIThree different standards are defined for LMI:-
ANSI's Annex D standard, T1.617
ITU-T's Q.933 Annex A standard
The Gang of Four
Because LMI is locally significant, each Frame Relay DTE in your network does not have
to use the same LMI type The main function of LMI is to allow the Frame Relay DTE and
DCE to exchange status information about the VCs and themselves Cisco has default
timers for their status enquiry and full status update messages. Status enquiry messages
are sent every ten seconds, by default. Every sixth message is a full status update message.
The three possible states that your PVC can be in are
Active— Active is good. Active means that everything is up and operational.
Inactive— Inactive is bad. Inactive means that you are connected to your Frame Relay
provider, but there is a problem with the far-end connection. The problem is most likely
between the far-end router and its connection to the Frame Relay provider. You should
contact your provider to troubleshoot the issue.
Deleted— Deleted is also bad. Deleted means that there is a problem between your
router and the Frame Relay provider's equipment. You should contact your provider to
troubleshoot this issue.
5. DLCI
Each VC has a unique local address, called a DLCI. Circuits are
identified by data-link connection identifiers (DLCI). DLCIs are
assigned by your provider and are used between your router and the
Frame Relay provider. In other words, DLCIs are locally significant.
This means that as a VC traverses various segments in a WAN, the DLCI
numbers can be different for each segment. DLCIs are locally
significant. The carrier’s switches take care of mapping DLCI numbers
for a VC between DTEs and DCEs.
Nonbroadcast Multiaccess
Nonbroadcast multiaccess (NBMA) is a term used to describe WAN
networks that use VCs for connectivity Frame Relay is a nonbroadcast
multi-access (NBMA) medium, which means that broadcast traffic is
not allowed to traverse Frame Relay traffic.
Split Horizon Issues
The main problem of NBMA environments arises when the network is
partially meshed for a subnet. This can create problems with routing
protocols that support split horizon.
6. Solutions to Split Horizon Problems
Given the preceding problem with routing protocols that use split horizon,
there are solutions that you can use to overcome this issue:
Use static routes instead of dynamic routing protocols. This is not a scalable
solution.
Disable split horizon with the no ip split-horizon command.This could create a
loop, If you are not careful
Have a fully meshed topology where every router has a PVC to every other
router. This can get expensive.
Use subinterfaces. This is your best option.
Ubinterfaces
A subinterface is a subset of an existing physical interface. As far as the router is
concerned, the subinterface is a separate interface. By creating subinterfaces,
each circuit can be on its own subnet. There are two types of subinterfaces:
Point-to-point— This maps a single IP subnet to a single subinterface and
DLCI.
Multipoint— This maps a single IP subnet to multiple DLCIs on a
subinterface.
7. Inverse-Arp
Frame Relay needs a mechanism to map Layer 3 addresses withLayer 2
Frame Relay DLCIs. This can be done through a static map command
(shown later in the configuration section) or through inverse-arp. Just
like Ethernet ARP, inverse-arp is used to map a Layer 3 address to a
Layer 2 address. However, Ethernet ARP maps an IP address to a MAC
address and inverse-arp works to map an IP address (or other protocol)
to a DLCI.
FECN (Forward explicit congestion notification)
This value in the Frame Relay frame header is set by the carrier switch
(typically) to indicate congestion inside the carrier network to the
destination device at the end of the VC; the carrier may be doing this to
your traffic as it is on its way to its destination.
BECN (backward explicit congestion notification)
This value is set by the destination DTE (Frame Relay device) in the
header of the Frame Relay frame to indicate congestion (from the
source to the destination) to the source of the Frame Relay frames (the
source DTE, the router). Sometimes the carrier switches can generate
BECN frames in the backward direction to the source to speed up the
congestion notification process. The source can then adapt its rate on
the VC appropriately.
8. Access rate
This is the speed of the physical connection (such as a T1)
between your router and the Frame Relay switch.
CIR (committed information rate)
This is the average data rate, measured over a fixed period of
time, that the carrier guarantees for a VC.
BC (committed burst rate)
This is the average data rate (over a period of a smaller fixed time
than CIR) that a provider guarantees for a VC; in other words, it
implies a smaller time period but a higher average than the CIR
to allow for small bursts in traffic.
9. BE (excessive burst rate)
This is the fastest data rate at which the provider will ever service the
VC. Some carriers allow you to set this value to match the access rate.
DE (discard eligibility)
This is used to mark a frame as low priority. You can do this manually,
or the carrier will do this for a frame that is nonconforming to your
traffic contract (exceeding CIR/BC values).
Oversubscription
When you add up all of the CIRs of your VCs on an interface, they
exceed the access rate of the interface: you are betting that all of your
VCs will not run, simultaneously, at their traffic-contracted rates.