Protocol
ISDN BRI
Basic Rate Interface · 2B+D
Lab ready Full lab
ISDN Basic Rate Interface providing two 64 kb/s B-channels plus a 16 kb/s D-channel for Q.931 signaling (2B+D). S/T and U interfaces differ electrically; LAPD carries D-channel frames. Still appears on legacy PBX trunks and some specialist access lines.
Tags
isdn2b+dlapdaccess
Sources
- ITU-T I.430 / Q.921 / Q.931
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