Frame Relay

Frame Relay is a fast packet-switching technology introduce in 1992. Since this technology falls into the category of packet-switching family, we should know the definition of packet switching.

Packet Switching is a store and forward switching technology for queuing networks where user messages are broken down into small pieces called packets. Each packet has its own associated overhead containing the destination address and control information. Packets are sent from source to destination over shared facilities and use a statistical time-division multiplexing concept to share the resources.

Fast Packet Switching is a combination of packet switching and faster networking using high-speed communications and low-delay networking. Fast packet is a “hold an forward” technology designed to reduce delay, reduce overhead and processing, improve speed, and reduce costs. It is designed to run on a high-speed circuits with low (or no) error rates.

Comparing the X.25 network with the Frame Relay Services, both use statistical TDM. The OSI layer used by the X.25 is the layer 3(Network). While the Frame Relay uses the Layer 2(Data Link). X.25 uses ACK and NAK, and requests retransmissions. The Frame Relay on the other hand, only requests retransmissions by higher-level protocols. The Packet/Frame Size of the X.25 is up to 128 bytes on average network and up to 512 bytes in some implementations. It also has a transmission speed of up to 64 Kbps. The Packet/Frame Size of the Frame Relay however, is up to 1610 bytes in networks and up to 4096 bytes in some vendor products. It has a transmission speed that starts at 56 Kbps up to 50 Mbps, Depending on the vendor.

Now, comparing Frame Relay and IP, Frame Relay is multiprotocol support and has a predictable and reliable performance. It also has a Robust Network management Capabilities. But it is only in WAN. IP on the other hand is an Any-to-any connectivity. But it does have a limited quality of service an security concerns. It is in LAN or WAN.

Frame Relay Selected for Wireless Data on GPRS, this is because it is widely deployed as a networking architecture. It is also base on the PVC from the PCU to the network device called a  Serving GPRS Support Node which operates at speeds up to 2.048 Mbps. The standards allow for the sharing of the circuitry from many devices by interleaving the data frames on the same physical channel. Also, it does minimize the overhead on the channel.