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New Member

PRI and bandwidth

I was asking a so called voice engineer about a PRI.

I asked him what the bandwidth of the PRI was and he was condescending and said:

"It isn't bandwidth, it is a PRI"

Isn't there still bandwidth associated with PRI's even if it is used for voice?

Hall of Fame Super Silver

Re: PRI and bandwidth

Yes, just like a regular 56K phone line. A PRI is composed of 23 B-channles and 1 D-channel where each channel is 64 kbps. So a full PRI is 1.536 Mbps. However either way you look at it, it will still allow for fixed number of calls (23) and you cannot send any more calls over it. So, the bandwidth concept does not directly apply to a PRI as it simply provides for up to 23 calls.



Hall of Fame Super Gold

Re: PRI and bandwidth

Perhaps the voice engineer forgot about the data capabilities of ISDN. Each channel is 64K digital clear channel, and can be aggregated using MLPPP for bandwidth-on-demand.

Cisco routers supporting voice also allow simultaneous data on PRI for any dial-up need that you may have.

Hope this helps, please rate post if it does!