Handoff

The transfer or control of a cellular phone call in progress from one cell to another, without any discontinuity.

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Handover

The passing of a call signal from one base station to the next as the user moves out of range or the network software re-routes the call.

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HCS

Hierarchical Cell Structure; the architecture of a multi-layered cellular network where subscribers are handed over from the macro to the micro to the pico layer depending on the current network capacity and the needs of the subscriber.

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HDLC

High level Data Link Control.

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HIPERLAN

High Performance Radio Local Access Network; a wireless local area network being standardized by ETSI (also HIPERLAN2).

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HLR

Home Location Register the functional unit responsible for managing mobile subscribers. Two types of information reside in the HLR: subscriber information and part of the mobile information that allow incoming calls to be routed to the mobile subscriber. The HLR stores the IMSI, MS ISDN number, VLR address, and subscriber data on supplementary services.

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HSCSD

High Speed circuit Switched Data; a special mode in GSM networks that provides higher data throughput by cocatenating a number of timeslots, each delivering 14.4bit/s, much higher data speeds can be achieved.

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HSPSD

High Speed Packet Switched Data.

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HTTP

HyperText Transport Protocol is a communications protocol used to connect to servers on the Web. Its primary function is to establish a connection with a Web server and transmit HTML pages to the client browser or any other files required by an HTTP application.

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HTTP Proxy

A proxy server that specializes in HTML (Web page) transactions.

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