e1 / isdn 30

[carl_townshend]

Hi all, can anyone tell me if these are the same, as they both have 32 channels ?

[allan.thomas]

PRI ISDN or ISDN30 is also known as E1 both have 30-channels and 2 D-channels.

Regards

Allan.

[rolf.stange]

Hey

This is not correct with the to D-channels.

An E1 has 30 B-channels 1 D-channel an 1 channel for synchronysation.

timeslot 0 = synchronysation

timeslot 1 to 15 = B-channel

timeslot 16 = D-channel

timeslot 17 to 31 = B-channel

[allan.thomas]

I agree E1 or ISDN30 is typically referred to as 30B+1D, 30 bearer channels for voice and data, and a single 'data' or 'delta' channel for signalling, plus a further channel synchronisation and maintenance.

Interpretations can be somewhat misleading concerning the syncronisation channel, and in some case reference as a data channel, hence 30B+2D

Apologies for the confusion..

Regards

Allan.