Free Essay

X.25 Protocol

In: Computers and Technology

Submitted By latchjohnson
Words 2304
Pages 10
X.25 Protocol

A history of the X.25 Protocol
Tim Elliott
Morrisville State College

X.25 is a Wide Area Network standard suite of protocols for packet switching developed by the International Telecommunication Union-Telecommunication Standardization Sector in the early 1970’s. It was designed to support traditional data networking over telephone wiring. Though widely used in the 1980’s, it has been largely replaced by newer IP standards such as frame relay. The purpose of this protocol is to effectively transmit data between different types of systems across a public data network. The main communication groups that ran this form of packet-switched network were the telephone companies but as technology has moved away from these slower forms, the public sector has seen this all but disappear in America. It should be said though that many places around the world still use this because of the cost to upgrade to newer hardware, but that market segment is shrinking quickly.

A history of the X.25 Protocol
In this paper, I will be talking about many of the technical aspects, the history and some of the situations where the X.25 protocol is still in use today.
In Section 1, I will talk about where it fits on the OSI layered architecture and discuss the Network and Data Link layer. In Section 2, I will describe some of the common equipment that this protocol used with the Physical Layer of the OSI model. In Section 3 I will discuss some of the problems that have been found from the protocol. Finally in Section 4, I will describe some of the areas that this is still in use today.
Section 1
The X.25 protocol truly encompasses the first three layers of the OSI model. Within the Data Link Layer, the protocols role is to exchange data across a physical link and assure that it comes through the other end intact. It has the ability to detect errors and make corrections while in use. The main procedure used by X.25 is LAPB, the Link Access Procedure Balanced. This was designed to be able to send frames between nodes in a way that was dependable and in a correct order so that the information would not become corrupted.
The first phase was the disconnected phase. This was the period that the node was not sending or receiving data. Although it was usually a phase that nothing was literally done, some data terminal’s sent out a signal before making a connection to verify that the node on the other end was not communicating with another machine. If the node on the other end was turned off, this would also alert the machine that there was no one to communicate with.
The second phase was the link setup. The node initiating the connection sent a Set Asynchronous Balanced Mode command frame, or SABM . The receiving node would reply with an acknowledgement that a connection could be made.
Once connected, there is an Information Transfer phase. This allows layer three to send its data packets to the node on the receiving end. Although it is an older standard, it has the ability to run full-duplex on over the telephone wires that this system typically runs on. When there was a high level of traffic, the cabling offered
Once all the packets are sent, the sending node sends a request to drop the connection in the Link Disconnection Phase. When the receiving node receives it, it verifies that it will drop the connection by sending a reply. If the receiving machine does not receive the request and has not received any packets within a limited time, it is assumed the transmission is done and drops the connection.

Because the X.25 protocol came out before the OSI model, its network layer was called the packet layer but translates to its equivalent. Any packet sent using the packet layer begins with a header that is three bytes long with the first four bits containing a General Format Identifier. This tells the node which of the two sequence numbers format is being use to send the data. It also contains a Logical channel number and packet type identifier. Attached to the data is a sequence number that tells the receiving node what packet to expect next. The packets will allow the receiving machine to know more data is coming, confirm data is sent and even run a parallel channel used for control information. If any data is corrupted or not received, the receiving node can send a message to stop the flow of data till it can get the missing data resent. If the sender does not send it, the receiver cannot ask for another file resent until the first one is received. Although it was possible for packets to be sent at a maximum size of 128 kbps, the most common size of data was 64 kbps. This was due to the hardware capabilities at the time although some standards such as X.21 could support up to 2 Mbps. Several virtual circuits could be routed through the cabling to make this a true multiplexing environment. This made X.2X series of protocols very popular when it was first introduced.
Section 2
A X.25 network is typically comprised of DTE’s (Data Terminal Equipment, DCE’s (data Communication Equipment, Pad’s (Packet Assembler/Disassembler) and a PSE’s (Packet Switching Node).
Data terminal equipment is the initiator or receiver of data that is sent over a serial connection, used on an X.25 network. The data it sends or receives is converted into a form that the user can understand in a graphical user interface shown on a monitor. As the name implies, this is where information will go and the circuit is ended. These machines can be terminals, personal computers, or network hosts. Many of the earlier, less powerful terminals, deemed “dummy terminals”, did not have the capacity to send out information that was suitable to go out over the network. These machines needed to be attached to Packet assembler/disassembler with data coming out of their async port. As terminals gained in power, PAD’s were no longer needed, and these terminals outgrew the need for the X.25 protocol.
When these devices, such as a character-mode terminal, are too simplistic to work on the network, they are attached to a Packet assembler/disassembler. This connects simple DTE’s with DCE’s by taking information the terminal had, and relaying it to the DCE in a way that a network device could understand and move. It has the ability to buffer information, convert the data, and then send out it out to a DCE. Oppositely it could receive packets, break them down so a dummy terminal can understand the data and relay it. These were really the external computing/network cards of lower end nodes. These were eventually phased out by the ever increasing power of terminals.
Data communication equipment (DCE) is the devices that connect to the terminals and the packet switching nodes. These are most typically modems and switches. Their function was to relay information between terminals and PSE’s. Other than just acting as a repeater for the signal, DCE’s had the important function of coding the data. This was where the sender could send data that had a redundant stream in case any data got corrupted along the way. The terminal receiving the information or another DCE for that matter, could see the error when compared to the redundant stream and disposed of it. This made for better error correction on the fly, but more data traffic to be used. Because you paid for your bandwidth by how much you used, this could double your operating costs when you have very few errors. This was a good option if you had a large amount of throughput and many machines, but if you had a small amount and had very few errors, the cost could far outweigh the gains.
Within the center of the network, are the packet-switching exchanges. These devices store and forward a bulk of a network’s data transmissions between DTE’s. These switches sent information to other terminals as a switching mode known as a virtual circuit. This was where it created and established connection between machines and then sent pre-allocated information that used a connection identifier instead of an address to send the data to. The virtual circuit would stay open until the session had ended. In cases where users wanted the connection to stay up permanently, they could use a permanent virtual circuit.
Section 3
A major disadvantage of using the X.25 protocol is performance when compared to newer protocols. Because it uses redundant data transfers, it can hamper the speed of your network. When errors are found, the terminal stops to figure out where the error came from by checking the redundant file sent. All this double checking slows the node down. Newer protocols drop corrupted packets and have all the packets resent. This speeds up the node because it is not searching or trying to fix errors, getting a replacement is quicker and easier. Because most of these older networks still have older telephone cabling, this further shows the networks down because telephone cables.
The lack of adaptability also hampered the protocol. Because it was set up for mostly old, unsophisticated devices, adding new machines that were more powerful would be a waste on the system. As machines grew in power, better forms of data transmissions were formed to fully utilize their potential. Because most businesses wanted newer devices, it made sense to phase this out.
When frame relay replaced X.25, it did packet switching on its network layer. When compared to Frame Relay, which did its switching on the data-link layer, it was noticeably slower.
Section 4
X.25 is still used today despite its many drawbacks compared to TCP/IP. One of the main areas where it is still seen today in the United States is in ATM and point-of-sale terminals. Because of the low data rates these machines use and virtually no reason to replace it, it’s still a good solution to use. Unfortunately the equipment that these machines use are getting rare and eventually they will all be replaced by newer networks. It has become more cost effective to replace it with newer machines that are in higher production. In Asia, the aeronautical business very much still uses X.25 to interconnect airfields. Because these networks still work, it makes very little sense to put a lot of money into replacing them. But as we have seen, with the shrinking amounts of X.25 hardware out there, it will inevitably be replaced by newer, more dependable networks. Even though most of the world has transitioned to tcp/ip, certain telecommunications companies are still using it as well for a consumer market. As of right now, about 2 million French users are using X.25 until the ISP shuts down the service by the middle of 2012. Solutions and Problems with X.25

The idea of making X.25 was to create a low cost alternative for data communication over public networks. In the early days of networking, it was costly to send any type of data because networking fees were so expensive to have. It was a major advancement to only have to pay for the bandwidth someone used. This allowed smaller companies to get connected to a network without paying a huge amount of money for doing very little. This lower cost helped networking become cost effective and spread to more and more companies. Another positive was the fact that the protocol could work on insufficient cabling. Since the network was not doing anything when not sending information, the cabling was not used and could handle the little traffic that it got. When there was a problem with sending data over the network, especially a poor one, X.25 incorporated error detection and correction which allowed the nodes to keep communicating and not have to restart due to dropped packets. This allowed many places to send data without having to replace all their wires, which lead to a spread of the X.25 protocol. For its time, the speed of the bandwidth was quite well. Although most terminals sent data at 64 Kbps and could send up to 128 Kbps, X.25 could support speeds of just 9.6 Kbps to 2 Mbps. There was also support for up to 4095 virtual circuits over a DTE-DCE link trough multiplexing.
A major problem facing X.25 was the lack of technology used in all aspects of it. Most of the terminals had very low abilities and as personal computers have gotten better, it has made many of the features redundant to have on a network.

Hunt, R. (1996). Frame relay: protocols, architecture, operation and performance. Computer Communications, 19, 830-847.

Arora, R.K., Khanna V. K. (1995). Design of a kernel for implementing communication protocols. Microprocessing and Microprogramming, 41, 469-485.

Kanna, V.KF. (1996). A suggested protocol for Internet access on PSDNs. Journal of Systems Architecture, 44, 909-912.

Katsavos, P., Varadharajan, V (1997). High speed network security. Computer Communications, 20, 832-847.

Tredinnick, I. (1995, June). X.25: A new lease on life with ISDN. Telecommunications, 29.6, 59.
West, C. (2010). Some notes on the history of protocol engineering. Computer Networks, 54, 3197 – 3209.

Djavanshir, R. (1996). A review and evaluation of networking technologies. Telematics and Informatics, Vol 13, pp. 33 – 48.

Purser, M. (1988). X.25 The Fulcrum for Network Standardization. Computer Communications, Vol 11, pp. 234 – 238.

(1998) X.25 Network Support. IBM AS/400e. Version 4 Manual

(2011) X.25 Protocol. Performance Technologies Inc. Manual

Similar Documents

Free Essay

Wan Connection Types

...What's the best WAN connection type for you? 14Comments more + * Email * Print * Add to Favorites * * Digg * Hacker News * LinkedIn * Reddit * Technorati By Warren Heaton August 16, 2000, 7:00am PDT When designing a wide area network (WAN), one of the most challenging issues is choosing the correct connection type. You need to consider several factors before implementation can begin—and a solid understanding of all the connection types is critical to making the right choice. Most carriers offer three connection types: 1. Circuit-switched connections 2. Packet-switched or cell-switched connections 3. Dedicated connections Each type of connection has its advantages and disadvantages. This article will summarize what each connection type has to offer, with consideration given to bandwidth, availability, cost, and ease of management. Circuit-switched connections Circuit-switched connections are currently the most popular type of WAN connection. Circuit switching transmits data streams and datagrams across dedicated physical circuits. To provide asynchronous dial-in and ISDN services, the telephone companies use circuit switching. Asynchronous dial-in The public switched telephone network (PSTN) uses circuit-switched technology to provide asynchronous services (otherwise known as normal telephone service). Asynchronous dial-in connections offer a low-bandwidth, easily managed, cost-effective solution......

Words: 817 - Pages: 4

Free Essay

Designing a Secure Network

...................................... 2 A Sample Design...................................................................................................................................3 Deciding if Frame Relay is Right for the Network.................................................................................... 4 Advantages of Frame Relay...................................................................................................................4 Disadvantages of Frame Relay.............................................................................................................. 5 Alternatives to Frame Relay.................................................................................................................. 6 X.25.................................................................................................................................................. 6...

Words: 3194 - Pages: 13

Free Essay


...The four major protocols for circuit switching and packet switching are as follows: • X.25 • Frame Relay • ATM or Asynchronous Transfer Mode protocol • TCP/IP X.25 is probably one of the very first of packet switching protocols. It performs really well, especially considering how long it has been around. X.25 uses a virtual circuit approach, mainly using POTS or plain old telephone service lines, which are different from lines such as ISDN. The POTS lines are analog copper lines, so they can experience a lot of errors. But, once the lines have been connected, X.25 connections are really reliable. It's quite an efficient way to send packets across various data networks, with the X.25 protocol redundant error checking at each of the nodes. Frame relay is different because it doesn't require the need for analog wires or overhead wires like X.25 does. But this means that Frame Relay doesn't have the added framing and processing that X.25 has that provide guaranteed data transfers. It also doesn't have link to link reliability. So if a frame is corrupted, it is discarded, which is different than TCP as it detects and recovers any and all discarded frames. Asynchronous Transfer Mode protocol is used with either a coaxial cable, twisted pair, or fiber. ATM also takes advantage of a 53-btye cell, having 48 application bytes and 5 bytes are allocated for the ATM headers. ATM shows a lot more enhancements over Frame......

Words: 487 - Pages: 2

Premium Essay

Indp 2

...Transmission Control Protocols or TCP is among the key methods utilized in Internet Protocol Suites. TCP has got two end systems, a web browser and a web server from which it operates. TCP provides delivery of a stream of bytes from a program on one computer system to another. Internet Protocols operate at a lower level compared to TCP. An IP is used for data transmission across a packet switched internetwork. In X on and X off signals, the X means transmitter. These types of signals are used to manage the movement of data between computer systems on an asynchronous serial connection. In X on, the bit configuration is the keyboard blend of Ctrl-Q and the Ctrl-S combination is for X off. There are two kinds of transmissions, parallel as well as serial. In parallel transmissions, several bits are transmitted on the same radio path at the same time, and are synchronized to a clock. Parallel devices can transfer much more data at a time because they have bigger data buses, instead of the one wire used in serial transmissions. Kudler Fine Foods Network Overview Introduction One of the considered “best fine food stores” around is the Kudler FineFoods. However, Kudler is in serious need of a network infrastructure upgradeof their old one. To introduce the latest technologies in data collection; company communication; and information protection while providing the bestdata speeds and network access; are the main goals of the enterprisenetwork. This huge step is significant as......

Words: 1083 - Pages: 5

Premium Essay

Packet Switching

...Некоммерческое Акционерное Общество АЛМАТИНСКИЙ УНИВЕРСИТЕТ ЭНЕРГЕТИКИ И СВЯЗИ Кафедра иностранных языков СЕМЕСТРОВАЯ РАБОТА №2 По дисциплине: «Английский язык» Технический перевод Специальность: 6M071900 – Радиотехника электроника и телекоммуникации Выполнила: Шаймагамбетова А.А. № з. к.: 12М3068 Группа СССп-12-01 Проверила: Бухина С.Б. __________________________ «_____»_________________________2012 год Алматы 2012 СОДЕРЖАНИЕ 1 Annotation 3 2 PACKET SWITCHING 3 3 КОММУТАЦИЯ ПАКЕТОВ 6 ТЕРМИНОЛОГИЧЕСКИЙ СЛОВАРЬ 10 СПИСОК ЛИТЕРАТУРЫ 11 Annotation This text describes packet switching, its modes and history. The main topic of this text is how packet switching works. Packet switching is a digital networking communications method that groups all transmitted data – regardless of content, type, or structure – into suitably sized blocks, called packets. The concept of switching small blocks of data was first explored by Paul Baran in the early 1960s. Independently, Donald Davies at the National Physical Laboratory (NPL) in the UK had developed the same ideas a few years. Two major packet switching modes exist; (1) connectionless packet switching, also known......

Words: 3704 - Pages: 15

Free Essay

Ntc 362

...Protocol Paper NTC/362 Fundamentals of Networking Protocol Paper Introduction Switching, whether it is packet or circuit, is an essential portion of any network. By not using the right equipment, or using it properly, you can cause massive lag time or jitter within your own system. This will result in packet collision, loss of data, and could result in loss of business. Open Systems Interconnection Protocol Model In order for two computers to be able to interchange data and information, they first must establish communicate with each other. Protocols allow for this communication to take place (Goleniewski). The Open Systems Interconnection (OSI) Model gives a logical design that is used for communication between systems. The OSI Model is layered with seven subcomponents: Application (7), Presentation (6), Session (5), Transport (4), Network (3), Data Link (2) and Physical (1). Each one of these layers presents a collection of services. These services are provided to the layers that are above and below that specific layer. In addition to these, the OSI Model also details the transfer of computer packets using layer protocols (Goleniewski). The Application layer has the role of maintaining the exchange of information between a computer’s programs and services on the network. The Presentation layer makes it possible for software applications to read information by formatting it. Support for connections between sessions is handled through the Session layer.......

Words: 1290 - Pages: 6

Free Essay

It530 - Unit 3 Frame Relay in a Wan

...medium-sized business that will need to consider WAN technology using Frame relay technology within the company for the future expansion to other towns and cities. The Frame relay analysis will include the operation of frame relay, what equipment is needed, what switching technologies are employed by frame relay and how frame relay is actually brought into the business premises. Frame Relay in a WAN Frame Relay Frame Relay is one of the most common WAN protocols. This high performance protocol operates at the Physical and Data Link layers of the OSI, performing any type of serial interface. This technology was developed at an attempt to resolve some of the communication problems that the other protocols would not. There was an increased need for higher speeds, an increased need for larger bandwidth efficiency, an increase in intelligent network devices that lower protocol processing, and the need to connect LANs and WANs. The Frame relay evolved passed the X.25 as a less careful, but less burdensome protocol designed to transmit packets across a network. (Horton, 2010) Frame relay is known all around the world in many different networks. There are many terms that describe and refer to Frame relay and Wide Area Networking in telecommunications. These terms are also noted when referring to Local Area Networking as well. The table below describes these terms. (Horton, 2010) Table 1 – Frame Relay Terms CIR Committed Information Rate – the minimum level of......

Words: 1228 - Pages: 5

Free Essay

Computer Science

...Part-1 1. What are common carriers, local exchange carriers, and interexchange carriers? A common carrier is a private company that sells or leases communication services and facilities to the public. Common carriers are profit-oriented, and their primary products are services for voice and data transmissions, both over traditional wired circuits as well as cellular services. Common carriers often supply a broad range of computer-based services, such as the manufacturing and marketing of specialized communication hardware and software. A common carrier that provides local telephone services (e.g., BellSouth) is commonly called a local exchange carrier (LEC), while one that provides long distance services (e.g., MCI) is commonly called an interexchange carrier (IXC). As the LECs move into the long distance market and IXCs move into the local telephone market, this distinction may disappear. 3. Explain how cloud architecture works. Cloud architecture is represented as a cloud with connection points. Users of circuit switched services lease the connection points (e.g., telephone lines) into the common carrier’s network, which is called the cloud. This architecture is very flexible and hides its internal details. Circuits can be established as needed between any computers attached to the cloud at any point. However, data can only be transmitted while a circuit is established, and only to the one location it connects to. These designs are simpler......

Words: 1686 - Pages: 7

Free Essay

Clns traffic between network elements and their respective OSS, making them a vital link between the service network and the network operations center (NOC). The solutions presented in this document will help telcos connect their SONET/SDH network elements to a router-based network using the Open System Interconnection (OSI) protocol, which simplifies the DCN and reduces equipment costs. Version History Version Number 1 Date April 28, 2004 Notes This document was created as a joint effort between Don Schriner in the Cisco CTO Consulting Engineering Group and Alliene Turner in Cisco IOS Documentation. This document was updated. This document was updated. 2 3 May 6, 2005 January 3, 2008 Contents The document presents the recommended Cisco architecture for building the OSI network. Several methods for implementing and scaling an OSI network are included with detailed configuration examples. Specific Cisco IOS software features such as Intermediate System-to-Intermediate System (IS-IS) multiareas, VLAN support for International Standards Organization Connectionless Network Service (ISO CLNS), Target Identifier Address Resolution Protocol (TARP), and IS-IS attach bit control are described. These architectures and software features are described in the following main sections: • •...

Words: 28935 - Pages: 116

Premium Essay

Mis589 Wk4 Mini-Case Mega Corp

...MIS589_WK4_Mini-case-MegaCorp_PC Questions: MegaCorp is a large manufacturing firm that operates 5 factories in Dallas, 4 factories in Los Angeles, and 5 factories in Albany, New York. It operates a tightly connected order management system that coordinates orders, raw materials, and inventory across all 14 factories. What type of WAN architecture and WAN service would you recommend? Why? Recommendations: When designing a WAN, numerous factors must be considered. Organizations attempting to connect multiple factories or offices and remote personnel must take into account a number of variables that will impact overall costs and network functionality. When designing and implementing wide area networks (WANs) that integrate voice, video, asynchronous and synchronous data and LAN traffic, all aspects of the organization's goals must be factored into the WAN design. Specific attention must also be paid to upfront cost, line charges, network throughput, security, and the inclusion of application and emerging technologies. Requirements will change, depending on whether you are creating a new network, modifying an existing network or integrating an existing network with other networks. Assuming there is an existing network, the next step is to inventory the network, identifying the circuits and all associated hardware (routers, firewalls) and software supporting the network, and summarizing all network-related expenses. Finally, access to network performance statistics (such as......

Words: 622 - Pages: 3

Premium Essay

Voice, Video, Network

...VOICE, VIDEO, AND DATA NETWORK CONVERGENCE VOICE, VIDEO, AND DATA NETWORK CONVERGENCE ARCHITECTURE AND DESIGN, FROM VOIP TO WIRELESS JUANITA ELLIS CHARLES PURSELL JOY RAHMAN Amsterdam Boston London New York Oxford San Francisco Singapore Sydney Tokyo Paris San Diego This book is printed on acid-free paper. Copyright 2003, Elsevier Science (USA). All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permissions may be sought directly from Elsevier’s Science & Technology Rights Department in Oxford, UK: phone: (+44) 1865 843830, fax: (+44) 1865 853333, e-mail: You may also complete your request on-line via the Elsevier Science homepage (, by selecting “Customer Support” and then “Obtaining Permissions.” Explicit permission from Academic Press is not required to reproduce a maximum of two figures or tables from an Academic Press chapter in another scientific or research publication provided that the material has not been credited to another source and that full credit to the Academic Press chapter is given. Academic Press An imprint of Elsevier Science 525 B Street, Suite 1900, San Diego, California 92101-4495, USA Academic Press 84 Theobald’s Road, London WC1X......

Words: 125371 - Pages: 502

Premium Essay

Unit 7 Assigment

...Unit 7 Assignments Multiple Choice: 1. A 2. A,B 3. A,B 4. B 5. D 6. B,D 7. A 8. A 9. C 10. D 11. C 12. C 13. B,C 14. C 15. B,C 16. B,D 17. C 18. D 19. C,D 20. B,C Key Terms: Switched circuit- A circuit created by the phone company in reaction to signaling (the user tapping telephone keys or a modem sending in the same digits), with the telco tearing down the circuit when the user is finished. Dedicated circuit- An electrical circuit created by a telco on behalf of a customer, with the circuit staying up all the time, dedicated for use by the one customer that ordered the circuit. Also known as a leased line, leased circuit, and point-to-point line Circuit switching- The overall process by which a series of telco devices called circuit switches connect a circuit from one customer device to the other, with the device’s logic taking incoming bits on one segment in the link and forwarding those bits out the matching outgoing segment, without storing the bits Packet switching- the process of forwarding customer data in a WAN by looking at the header of the messages sent into the WAN by the customer and making a per-message decision as to where to forward each message. Leased line- A physical link between two locations, provided by a telco, that allows two-way communication between sites. Because the customer does not own the physical line between sites, but rather pays a monthly fee for the......

Words: 1047 - Pages: 5

Premium Essay

Management Sciences

...Chapter 1 Data Communications Introduction 1 Chapter Objectives: Defined data communications Introduced data communications needs Communications model Overview of networks Introduce Internet 2 Data, Data Communication Data is an entity that convey some meaning based on some mutually agreed upon rules/conventions between a sender and a receiver. Data Communication deals with the transmission of signals in a reliable and efficient manner 3 Data Communication Topics covered include: Signal Transmission Transmission Media Signal Encoding Interfacing Data link control Multiplexing 4 Computer Science and Data Communications Merger In 1970s and 1980s The computer communications revolution has produced several remarkable facts. There is no fundamental difference between data processing (computers) and data communications (transmission and switching equipment). There is no fundamental difference among data, voice, and video communications. The distinction among single processor computer, multiprocessor computer, local network, metropolitan network, and long-haul network has blurred. 5 Today’s Trends Three different forces have consistently driven the architecture and evolution of data communications and networking facilities: Traffic growth Development of new services Advances in technology 6 Communication Traffic Both local (within a building or building complex) and Long distance having transmission of Voice, video and data The increased emphasis on office......

Words: 2260 - Pages: 10

Free Essay

Ntc 362

...Kudler Fine Foods Integrative Network Design Project Kudler Fine Foods has requested for an overhaul of its computer network infrastructure to a more efficient networking system to provide broader network communications to other stores. The service request calls for changing the administration network to a WLAN, design a WAN to link all of it stores, and add VoIP to all stores. Kudler Fine Foods need to communicate to its entire store locations so a Wide Area Network (WAN) needs to be designed with keeping the network within its budget and high end service in mind. To meet this requirement Kudler Fine Foods will purchase a Frame Relay service from its telecom provider. There are other methods for designing WANs then using a Frame Relay like X.25 and ATM, however, my initial choice was based by performance measures, cost, and network expansion to Kudler Fine Foods network requirements. All of its store locations will be using full and fractional T-1 lines which its headquarters location will use full T-1 while other locations will use fractional. In addition, the equipment used in the WAN design will be Data Terminal Equipment (DTE) and routers with plug-in WAN Interface Card (WIC) that will provide and efficient communication link to all of its stores. Further, a dual-hub network topology will be the used to expand the network as well as reduce the number of Permanent Virtual Circuit (PVC) connections while still maintaining redundant connections for faults that occur. A......

Words: 669 - Pages: 3

Free Essay


...Protocol Choices April 28, 2013 Team 5 (John Castro, Ruben Barragan, Teri Jordin, Saul Nolasco) There are many choices to make when you are deciding how your network will communicate with each other. There are a lot of protocols to take into consideration that will help make this possible. We have decided that for our WAN protocols, we will go with using frame relay. We will explain why we have chosen to go with frame relay, but first we will explain why the other choices are did not fit our needs at ABC company. HDLC is one of the protocols that we had a hard time coming to a conclusion with. It is a very good protocol and could have done well for the ABC Company but there are a few things that come with HDLC that made us come to the final decision of why not to use it. First of all, HDLC is a type of point-to-point protocol, which means that it costs a lot more money to have. The reason why it will cost more is because this means that every different branch has to be connected to each other. Almost like in a mesh topology form and that is wasting a lot of money there. PPP is the other protocol that we had a hard time deciding whether or not we were going to use over the other two. PPP is another point-to-point protocol that networks use in order to be able to communicate with each other. As a matter of fact, PPP is an acronym for point-to-point protocol. Once again, we have decided that PPP will waste too much money because every branch will need......

Words: 855 - Pages: 4