Introduction
In computer networking and telecommunications, Multi Protocol Label Switching (MPLS) is a data-carrying mechanism that belongs to the family of packet-switched networks.
When it comes to getting network traffic from point A to point B, no single way suits every application. Voice and video applications require minimum delay variation, while mission-critical applications require hard guarantees-of-service and rerouting.
So far, only circuit-switched networks have provided the differentiated services and guarantees required by many of these applications. But a new technology called Multiprotocol Label Switching (MPLS) is changing all that. With MPLS, you can support all the above applications on an IP network without having to run large subsets of the network with completely different transport mechanisms, routing protocols, and addressing plans.
Although the standard is a work in progress, many vendors and service providers are announcing MPLS products and services. As such, now seems like a good time to learn how the technology works, how it can be deployed, and what issues still need to be addressed.
MPLS operates at an OSI Model layer that is generally considered to lie between traditional definitions of Layer 2 (data link layer) and Layer 3 (network layer), and thus is often referred to as a "Layer 2.5" protocol. It was designed to provide a unified data-carrying service for both circuit-based clients and packet-switching clients which provide a datagram service model. It can be used to carry many different kinds of traffic, including IP packets, as well as native ATM, SONET, and Ethernet frames.
MPLS was originally proposed by a group of engineers from Ipsilon Networks, but their "IP Switching" technology, which was defined only to work over ATM, did not achieve market dominance. Cisco Systems, Inc. introduced a related proposal, not restricted to ATM transmission, called "Tag Switching" when it was a Cisco proprietary proposal, and was renamed "Label Switching" when it was handed over to the IETF for open standardization. The IETF work involved proposals from other vendors, and development of a consensus protocol that combined features from several vendors' work.
One original motivation was to allow the creation of simple high-speed switches, since for a significant length of time it was impossible to forward IP packets entirely in hardware. However, advances in VLSI have made such devices possible. Therefore the advantages of MPLS primarily revolve around the ability to support multiple service models and perform traffic management. MPLS also offers a robust recovery framework that goes beyond the simple protection rings of synchronous optical networking (SONET/SDH).
The direction of this paper is to describe a telecommunications switch and show its purpose and multitasking abilities. This paper will use the AT&T 5ESS Switch to give a real world example of a top rated telecommunications switch. The end result will be an understanding of how a switch works and what it can do. Also, it will show why the AT&T 5ESS Switch is #1 in today's telecommunication world.
The internet explosion has changed how we go about our everyday lives. The thirst for information and the need to ‘always be connected’ is spawning a new era of communications. This new era will continue to spur the need for higher bandwidth technologies to keep pace with processor performance. Because of Moore’s law, computing today is limited less by the computer’s performance than by the rate at which data can travel between the processor and the outside world. Fiber-optic solutions are replacing copper-based solutions, which can no longer meet the bandwidth and distance requirements needed for worldwide data communications [3]. Over the last decade, optical communication technologies have migrated steadily from long-haul backbones to the network edge, invading metropolitan area networks (MANs) and campus-level ...
Token ring networks have since declined in usage and the standards activity has since come to a standstill as switched Ethernet has dominated the LAN/layer 2 networking market.
The system chosen to replace the legacy PBX switching system will be the NEC’s NEAX 2000 IPS. The headquarters of ACME Electronics is spread between four buildings. The NEC NEAX 2000 IPS supports distributed processor architecture. This means that the processing requirements of the system are shared between more than processor. This allows for faster response times and redundant operation. If one processor fails, the other can take over. Two of the four buildings are equipped with 1 Pentium 200 MHz Processor dedicated to the inter-communications system.
Parker, T., & Siyan, K. (2002). TCP/IP Layers and Protocols | Overview of TCP/IP | InformIT. Retrieved November 2013, from http://www.informit.com/articles/article.aspx?p=28782&seqNum=3
Sending data through the internet efficiently has always posed many problems. The two major technologies used, Ethernet and Asynchronous Transfer Mode (ATM), have done an admirable job of porting data, voice and video from one point to another. However, they both fall short in differing areas; neither has been able to present the "complete" package to become the single, dominant player in the internet market. They both have dominant areas they cover. Ethernet has dominated the LAN side, while ATM covers the WAN (backbone). This paper will compare the two technologies and determine which has a hand-up in the data trafficking world.
In simple terms, the OSI model defines a networking framework for implementing protocols. Is defines seven levels to accomplish this. Control is passed from one level to the next, starting at the Application level (Level Seven) and working its way through the levels until it reaches and completes Level One, the Physical level. Once this cycle has been completed, control moves to the next station on the network and back up the hierarchy.
Explain how the two important transport protocols deliver messages on behalf of the application and discuss the differences between them
Within the last five years, businesses have begun to need to share data across wide areas. This has prompted efforts to convert principally LAN-based protocols into WAN-friendly protocols. The result has spawned an entire industry of consultants who know how to manipulate routers; gateways and networks to force principally broadcast protocols across point-to-point links. Frequently the protocol of choice has been TCP/IP which is also the primary protocol run on the Internet. The emerging ubiquitous ness of TCP/IP allows companies to interconnect with each other via private networks as well as through public networks.
Digital Subscriber Line new technology that takes advantage of standard copper telephone line to provide secure, reliable, high-speed Internet access. DSL refers to the family of digital subscriber line technologies, such as ADSL, HDSL, and RADSL. Connection speed for DSL ranges from 1.44 Mbps to 512 Kbps downstream and around 128 Kbps upstream. Unlike traditional connections DSL such as analog modems and IDSN, DSL deliver continuous “always on” access. That means multimedia-rich websites, e-mail, and other online applications are available anytime. DSL makes it possible for you to remain online even while you’re talking on the telephone-without jeopardizing the quality of either connection. DSL is available in a spectrum of speeds. Some are best home use, while others are designed to accommodate rigorous business demands. Whether for business or the home, DSL, offers unsurpassed price/performance value compared to other online options. There are the five facts that one should know about DSL. It is remarkably fast. With DSL service, you can benefit from Internet speeds that are up to 12 minutes faster than a typical ISDN connection and 50 times faster than traditional 28.8 Kbps modems. This means that in the 12 seconds it takes to read this information, you could have downloaded a 2 megabyte presentation file or web photograph. It would take 10 more minutes (600 more seconds!) to download the same with a traditional 28.8 Kbps. It’s highly reliable. One can depend on DSL because its proven technology takes full advantage of the existing telecommunications infrastructure. It’s inherently secure. DSL network provides a dedicated Internet connection via private telephone wires, you can bypass dial-up intruders or shared network hackers. Unlike traditional dial-upp modems or cable modems. DSL protects your valuable data with the most secure connection available. It’s surprising affordable. DSL is widely recognized as the most cost-effective connectivity solution for small buisness. DSL delivers industrial- strength like speed to multiple users at only 25% of typical TI costs. There is no better price option available. DSL is also an exceptional value for home users. At about $2 a day for services that meets the needs of most people. The connection is always on. It’s ready to run every minute of the day. There’s no more logging on and off. No more busy signals or disconnects. This gives you the freedom to focus on what you want to accomplish on line rather than focusing on trying to get connected.
TCP/IP operates at both levels 3 and 4 of the OSI model. The TCP portion of TCP/IP operates at level 3 (Network) as its primary function is to control the flow of data. IP operates at level 4 (Transport) of the OSI model. IP is the protocol responsible for the actual transmission of packet across the network.
In packet switching the data which is to be transmitted is divided into the packets. In this switching the communication path is not dedicated to one communication party but one path or link is used by the packets from different parties. During transmission the packet finds the path to the destination. The paths for the transmission are not defined from the source and they are decided when the packet has reached a certain node. The packet contains the header that carries all the information about the IP addresses of the source and the destination. With the help of this information the switches and the routers in the paths decides which hops are used to reach the specific destination.
The primary goal in routing multicast connections is to make efficient use of the network resources and to establish fast connections for data transmission. The network is often defined by a graph G(V,E) . Multicast routing protocols are been used in practical systems such as multicast backbone(M bone).M bone chooses the shortest path to each destination using the IP routing mechanism.Multicast routing in ATM Switch performs two basic functions such as switch and queuing.
Kozierok, Charles M. The TCP/IP Guide: A comprehensive, illustrated Internet protocols reference. San Francisco: No Starch Press, 2005.
· Switches – Subdivide a network into smaller logical pieces. Operates from the Data Link layer of the OSI model. By having multiple ports, they can make better use of limited bandwidth and prove more cost efficient then bridges. Each port on the switch acts like a bridge, and each device connected to a switch effectively receives its own dedicated channel. In other words, a switch can turn a shared channel into several channels.