Frame Relay

 Frame Relay is a way of sending information over a WAN by dividing data into packets
 It operates at the Physical and Data Link layers of the OSI reference model
 It relies on upper-layer protocols such as TCP for error correction
 Frame Relay is a switched data link-layer protocol that handles multiple virtual circuits using (HDLC) encapsulation
 Frame Relay interface can be either a carrier-provided public network or a network of privately owned equipment, serving a single enterprise
Frame Relay –benefits
Reduced internetworking costs
 Statistically multiplexed traffic from multiple sources over private backbone
networks can reduce the number of circuits and corresponding cost of bandwidth
 Lower Equipment Costs
 Lower cost than dedicated leased lines
Increased performance & reduced network complexity
 Reduces the amount of processing (as compared to X.25)
 Efficiently utilizing high speed digital transmission lines, frame relay can improve performance and response times of applications.
Increased interoperability via international standards
 Frame relay can be implemented over existing technology
 Access devices often require only software changes or simple hardware modifications to support the interface standard
 Existing packet switching equipment and T1/E1 multiplexers often can be upgraded to support frame relay over existing backbone networks.
Frame Relay overwiew
Packet Switched
Uses Virtual Circuits (Connection Oriented Service)

 Logical connection created between two (DTE) devices across a Frame Relay packet-switched network (PSN)