释义 |
Reference Model The ITU-T specifications for integrated services digital network (ISDN) use an alphabetical reference model to describe the various Reference Points (i.e., connection points or interfaces) on the customer side of the network.Those points are R, S,T, U, and Q, as illustrated in Figure R-1. See also Reference Point R, Reference Point S, Reference Point T, Reference Point U, and Reference Point Q. 74570c18.qxd 9/12/07 12:39 AM Page 413 |