[Asterisk-doc] Connecting to a PRI

[Roderick Montgomery]

Mats Karlsson wrote:
 > Jeff Gehlbach wrote:
 >
 >>I can't comment on E1, but one slight correction on PRI channelization
 >>terminology: the "D" designation of the signalling channel stands for
 >>"delta", not "data".  The same applies for the 16Kbps "D" channel used
 >>in BRI.
 >
 > And Jeff, the D channel is data and B is for bearer in the ISDN language.
 >
 > The D channel is used for signaling and data transfer like text messages
 > between ISDN devices.
 >
 > So the doc is correct on this point.

Mats, the D channel carries control messages and is frequently -- though 
incorrectly -- called the "data" channel. This confuses many newcomers to 
digital telephony, because the B channels are also capable of carrying data.

The correct name of the D channel is "delta," and the name for a B channel 
is "bearer." In addition to being symantically correct, we should avoid 
mis-naming the D channel as a "data" channel to prevent confusion.

Please feel free to verify; google for "isdn delta bearer".

All the best,
rm
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  Roderick Montgomery   rod at thecomplex.com   <URL:http://thecomplex.com/>
the fool stands only to fall, but the wise trip on grace... [Sarah Masen]
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