The purpose of this papers it to examine in detail the operation of one of the wide area network that we discussed in class. This paper discusses the difference between frame relay networks and other point to point networks, advantages, addressing schemes, and different protocols supported. The paper will explain virtual circuits briefly before moving to its other characteristics because they are the key to understanding frame relay concept in general. Other than virtual circuits, we will see its addressing scheme, how frame relay guaranty bandwidth with its committed information rate and how to detect and avoid congestion.
Frame relay is an implementation of a wide area network through packet switching. Frame relay offers more benefits than simple point to point wide area networks. It does not require a dedicated leased line unlike other point to point networks. Frame relay networks allow more than two network devices to attach to the same network. Some of the reasons why Frame relay is an efficient way of implementing wide area networks are the use of virtual circuit and having their own addressing scheme. Frame relay has its own data link header and trailer. They have their own protocol called data link connection identifier (DLCI). Frame relay networks relay one access links which are virtual circuits. The difference between frame relay networks and point to point networks is that in point to point, the leased line runes from one location to the. Each location will require the presence of its own router. In frame relay, the leased line run from routers to special frame relay switches.
Frame relay is considered packet switched network because all frames are send through different hops by the service provider which have multiple routers interconnected to each other. A leased line is installed between the frame relay switch and a one of the interconnected routers in the cloud. This leased line creates an access link. The devices located in the customer’s premises are called DTE (Data terminal equipment) whereas the equipment that is owned by the service provider is called Data circuit-terminating equipment (DCE) which is located in the frame relay network. There is a logical path between each DTE. This logical path is what is called virtual circuit (VC). There are two types of virtual circuits: Permanent Virtual Circuit (PVC) and Switched virtual circuit. PVC is established and configured by the telecom service provider. SVC is dynamically allocated to the user and depending on how much network bandwidth the customer is utilizing. Full meshed frame relay network is when there is direct permanent virtual circuit between all sites. Partial mesh network is where there is some but not all of the links are PVCs.
Each router has an address that is used to identify itself and interact with the other router. This
Address is called DLCI. Two routers communicate based their DLCI, establish a virtual circuit and whenever...