FRAME RELAY
A medium-performance, frame-oriented Layer 2 protocol standard for LAN internetworking. Evolved from packet-switching and ISDN, frame relay tranmission uses either a PVC predefined point-to-point connection or SVC, established on a call-by-callbasis. Unlike packet=switching, once a frame enters the network it is not unpacked until delivered to its destination, allowing much higher throughputs through intermediate devices.
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