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Desert View Frame Relay Documentation
Frame Relay will be implemented on the T1 link between the Public Access router and the Internet Service Provider.

• DLCI number: 69
  
• Value of the CIR: 1544 Kbps
  
• Data communication equipment needed to implement Frame Relay on the router:
  WIC-1DSU-T1: 1-port Serial with Fractional T1/T1 DSU/CSU WAN Interface Card

Frame Relay Benefits

• Cost – The pricing on a Frame Relay link is based on the committed information rate (CIR) promised by the provider, which is less than the cost of a dedicated link of same speed.
• Speed – The CIR commits the service provider to a minimum guaranteed rate, but in times of low traffic, the maximum possible speed is limited only by the capacity of the link itself. The CIR of this link is 1.544Mbps, the same as a T1 line, but rates up to 2Mbps are typical on Frame Relay links, and can theoretically go even higher.
• Efficient Bandwidth Usage – Frame Relay can automatically adjust to congestion with the use of Forward Explicit Congestion Notification (FECN) and Backward Explicit Congestion Notification (BECN) frames. These tell the sender to reduce the transmission speed, and tell the Frame Relay network to find alternate paths around the congestion.
• Multiplexing – DLCI numbers allow multiple logical conversations to take place simultaneously on the same physical link. If in the future the Washington Elementary School District needed to be connected to networks in other school districts, this could easily be accomplished using permanent virtual circuits (PVCs) across the Frame Relay network.
• LMI – If in the future the school district needs to be connected to other school district networks, the use of LMI extensions can make configuration and maintenance of the link easier. LMIs can be used to transmit keepalives and determinate the status of PVCs on the Frame Relay network, dynamically create and update the Frame Relay map, and to send multicasts to multiple destinations.