HDLC

networking

Stands for: High-Level Data Link Control

High-Level Data Link Control - the ISO framing standard that underlies a whole family of serial protocols.

HDLC defines how to delimit and error-check frames on a synchronous serial link, and it is foundational: X.25's LAPB, Frame Relay, ISDN's LAPD, and Cisco's default serial encapsulation are all HDLC-derived. It descends from IBM's SDLC, generalized by ISO into a vendor-neutral standard. You rarely configure 'HDLC' by name, but its frame structure is quietly under much of classic WAN networking.

Also known as: hdlc, high-level data link control, lapb

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