摘要 |
<p>PCT No. PCT/GB95/01856 Sec. 371 Date May 19, 1997 Sec. 102(e) Date May 19, 1997 PCT Filed Aug. 4, 1995 PCT Pub. No. WO96/04726 PCT Pub. Date Feb. 15, 1996A communications path not using a deterministic signal frame structure is provided with performance monitoring by using known Alarm Indication Signal (AIS) type monitoring on the path but scrambling traffic signals in a scrambler to avoid them being mistaken for an AIS. At the receiving end of the path the received signals are monitored for the presence of an AIS, followed by a descrambler to unscramble the received signals before transmitting them to a receiving piece of CPE. An adverse state detector may also be provided, to avoid the scrambler scrambling traffic signals to that they look like an AIS.</p> |