to Karthikeyan S:
BCF is Base Control Function, it is logical entity for Nokia base stations , phisically it is unit in base station, logically in is a main idetnifier for base station site on nokia bsc…
PCM – pulce code modulation , it is common name for G.703/G.704 protocoltransmission links, G.703 describes phisical data of transmission, i.e. duration of pulse, voltage etc, G.704 describes logical structure of the G.703 frames…. it is layer 1 in GSM terms
LAPD link is layer 2 protocol, there are 2 types of LAPD links: BCF SIG and TRX SIG, BCF SIG used to manage BCF, i.e. whole base station, to lock/unlock base station, to deliver alarms from site to BCS, but it is used only for managing, all GSM signalling goes through TRX SIG …
alex
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