lap

LAP

(1) (Link Access Procedure) An ITU family of data link protocols that are subsets of HDLC, which was derived from IBM's SDLC protocol. See HDLC.

LAP-B (Link Access Procedure - Balanced)
LAP-B is used in X.25 networks. Multilink Procedure (MLP) is a LAP-B extension that supports multiple, simultaneous links for increased throughput.

LAP-D (Link Access Procedure for the D Channel)
LAP-D is used for the D channel in ISDN networks and is defined in the ITU Q.920 and Q.921 recommendations. See ISDN.

LAP-M (Link Access Procedure for Modems)
LAP-M is used in V.42 error correcting modems. Although transmission between the computer and modem is asynchronous, transmission between LAP-M modems is synchronous.

LAP-X (Link Access Procedure Half-Duplex)
Used in ship-to-shore transmission.

(2) (Link Access Protocol) The data link protocol in an AppleTalk network. Support for the various data link types are known as ELAP (Ethernet LAP), TLAP (Token Ring LAP), FLAP (FDDI LAP) and LLAP (LocalTalk LAP).

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lap¹

the area formed by the upper surface of the thighs of a seated person

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lap²

1. a rotating disc coated with fine abrasive for polishing gemstones

2. any device for holding a fine abrasive to polish materials

3. Metallurgy a defect in rolled metals caused by the folding of a fin onto the surface

4. a sheet or band of fibres, such as cotton, prepared for further processing

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lap [lap]

(civil engineering)

The length by which a reinforcing bar must overlap the bar it will replace.

(materials)

An abrasive material used for lapping.

(metallurgy)

A defect caused by folding and then rolling or forging a hot metal fin or corner onto a surface without welding. Also known as fold.

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LAP - LISP Assembly Program. The assembly language embedded into early Lisp. LAP was also used by the Liar compiler for MIT Scheme and MACLISP. [Sammet 1969, p. 597].