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Primary Rate Interface equipment: overview
553-2901-200 Standard 11.00 August 1996
Note:
X11 release 14 requires QPC757 vintage B or higher. A QPC757
vintage C is required if the ISL Revert to Conventional Signaling feature
is configured. X11 release 15 requires a QPC757 vintage C or later. The
QPC757 vintage D is recommended for combination ISL/PRI networks
using NACD or Network Message Services and ISL networks using
modems.