V110 » History » Revision 2
Revision 1 (laforge, 05/01/2022 03:51 PM) → Revision 2/7 (laforge, 11/20/2022 07:49 PM)
h1. ITU-T Recommendation V.110 V.110 is an ITU standard for bit-rate adaptation of low-speed async serial signals (600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 19200, 24000, 28800 or 38400 bit/s) to 64 kbit/s 64kBps ISDN B-channels. It was primarily used in the context of interworking between GSM Circuit Switched Data (CSD) and ISDN. h2. Details h3. Frame structure The protocol uses an 80bit (10 byte) frame. The Frame contains a frame sync pattern (similar to e.g. E1 TS0 or TRAU frames) consisting of the first byte and the first bit of every following byte. Each frame consists of * 17 bits of above-mentioned frame sync pattern plus: * 48 D-bits (D1..D48) * 7 E-bits (E1..E7) * 8 S/X-bits (S1,S3,S4,S6,S8,S9) h3. Rate Adaptation Functions h4. RA1 The rate-adaptation function RA1 converts from the V-series rates (e.g. 2400bps) to an intermediate rate of 8/16/32/64 kbit/s. h4. RA2 RA2 converts from the RA1 output rate of 8/16/32/64 kbit/s to 64 kbit/s
