#Frame relay simplediagrams serial

Other protocols that use HDLC frames include SDLC, Frame Relay, and X.25. We have discussed HDLC in earlier sections, and the HDLC frame is given below. This results in simple link management procedures, and more efficient data transfers.įrame Relay Protocol: FR is an HDLC protocol based network. Unlike SVC, there is no call setup, and call termination procedures in PVC. SVCs are advantageous when you have burst traffic, and you don't want to block the network bandwidth for a given virtual circuit 24hours a day. If there is some more data to be transmitted at a later time, an SVC is negotiated again.

Call termination: The virtual circuit between end nodes is terminated.

An SVC call is terminated after a certain period of idle time

Idle: The connection between end nodes is still active, but no data is transferred.

Data transfer: Data is transmitted between the end nodes over the virtual circuit.

Call setup: The virtual circuit between two Frame Relay end nodes is established.

An SVC communication session has four states: Switched Virtual Circuit(SVC): A switched virtual circuits (SVC) provide temporary connection between end nodes (DTEs) across a Frame Relay network.

Note that PVC does not terminate the virtual circuit even when there is no data being transferred between the end nodes.

Idle state: No data is transferred between the end nodes.

Data transfer state: Data is transmitted between the end nodes over the virtual circuit.

A PVC can have two operational states as given below:

This type of connection (PVC) is used when it is required to consistently transfer data between the end nodes. The virtual circuit is always available irrespective of whether any data is being transmitted or not. Permanent Virtual Circuit (PVC): PVC is a permanent connection between the end nodes (DTEs) within a Frame Relay network. A virtual circuit provides a logical connection between end nodes for the flow of information. In data circuits, the term virtual circuit is also used in similar sense. Remember that a circuit provides connection between end nodes by means of an electrical connection. The DLCI configured on both spoke routers is the same as the DLCI is locally significant between the WAN Cloud and each customer.Before going ahead with Frame Relay protocol, and its operation, we discuss virtual circuits. The spoke routers have only one virtual circuit configured to reach the hub router.

#Frame relay simplediagrams serial

The clock rate defines the speed on the serial interface interface Serial0/0/0Ĭlock rate 2000000 Frame relay spoke routers configuration (R1 and R2) The encapsulation frame-relay command is mandatory on the main serial interface before configuring frame-relay sub interfaces. The DLCI number defines a single virtual connection through the WAN and are the Frame Relay equivalent to a hardware address. Each frame relay sub-interface is mapped with the DLCI number of the corresponding circuit configured in the Packet Tracer WAN emulation Cloud.

The hub router is configured with two sub-interfaces to create a virtual circuit with each spoke. Virtual circuits, LMI types, and DLCI are configured using the Serial and Frame Relay tabs of the 'Cloud-PT' device.įrame Relay configuration - ISR router configuration Frame relay hub router configuration (R0) Router are connected to the Frame Relay switch using serial connections. This device can be configured as a Frame Relay switch. The increased error-handling sophistication at end stations and the improved reliability of communication lines allows the Frame Relay protocol to discard bad frames and thus eliminate time-consuming error-handling processing.Ĭisco Packet Tracer 7.2.1 includes a 'Cloud-PT' device for WAN emulation.In addition, each device can use more than the allowed bandwidth as necessary, and thus operate at higher speeds. Consequently, many virtual circuits can exist across a given transmission line, which is an improvement compared to dedicated leased lines. Virtual circuits consume bandwidth only when they transport data.The success of the Frame Relay protocol is based on the following two factors: Frame Relay offers an attractive alternative to both dedicated lines and X.25 networks for WAN links. Frame Relay is a protocol standard for WAN internetworking which provides a fast and efficient method of transmitting packets through the network.