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Cross Connections

Using the Cross Connect Channel or the Cross Connect Span message, the host connects two physical channels or spans. Both spans must already have a Logical Span ID. Dialogic recommends taking both ends of the connection out of service first. When either of these messages are used, the connection is made regardless of any line or trunk configurations or formats currently set.

Cross Connect Channel

Connect the data paths of the two channels. Both Channel A and Channel B should be out of service, except when cross connecting T1 and E1 channels. No signaling information can be used to detect either channel releasing. The host must use the Cross Disconnect Channel message to tear down the connection.

Cross connecting T1 and E1 channels causes automatic PCM conversion (A-law/µ-law). By default, channels on T1 spans are µ-law, and channels on E1 spans are A-law. To disable conversion, configure both channels with the same format by using the PCM Encoding Format Configure message. You must disable conversion when you are connecting through an ISDN D channel.

Cross Connect Span

Connect all data paths on Logical Span ID A to data paths on Logical Span ID B. You cannot cross connect a T1 span with an E1 span without PCM conversion. Multi-frame synchronization is not maintained between two cross-connected spans.

Cross Disconnect Channel

Disconnect the data paths of the specified channels.

Cross Disconnect Span

Use the Cross Connect Span message to disconnect all data paths of two spans that were previously connected.

Range of channels provided by T1 or E1 transmission service. A physical span is a group of channels taking up a single physical wire. A logical span is a group of channels taking up less than a single logical wire, or carried over more than one physical wire.
Digital communications link - voice, data, and video at a 1.544 Mbps rate (24 64 Kbps channels)
A digital communications link - voice, data, and video at a 2.048 Mbps rate; 30B/2D or 31B/1D (ISDN); non-North American version of T1.
See Pulse Code Modulation.
See Integrated Services Digital Network.