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small office

small office

small office

I'm new to the IP office, so I appoligize for my ignorace. We were trying to determine if the Small office could use a T1 for voice connectivity? The tech notes state the T1 is able to use 64kb clear channel and 56k data only. With no signaling in clear channel, I don't see how it is possible to order a T1 for voice from the LEC. Anybody run into this yet. Thanks in advance.

RE: small office

A DS1 circuit with 23 ports available for user calls with the 24th port used for telco signalling control is provided by telco as ISDN PRI. This is known as a clear channel (a.k.a. common channel) circuit. Each user channel can communicate up to 64 kbps.

A DS1 circuit with all 24 ports available for user calls uses robbed bit signalling, meaning that one bit from each port is robbed for telco signalling control. This reduces each user channel's bandwidth to 56 kbps. This circuit is typically referred to as a T1.

All that being said, for a small office I can't imagine needing either 23 or 24 lines for incoming/outgoing PSTN calls. Telco should be able to bring in a fractional DS1 circuit for a cheaper price. That or else a small hunt group of loop start or DID lines.

Have you checked on this?

RE: small office

from IP ip office product discription:-

IP400 Office T1 PRI Card

the Ip Office T1 PRI card provides a single primary rate interface for supporting fractional leased lines, of up to 256k bandwith on IP & Frame Relay services

Not available in all territories, check for availability

Like greg I would suggest that a system of this size would not require Primary rate lines, the 4 circuit (8 channel) Bri should be more than enough

RE: small office

The small office (IP401 in UK I think - just got released in the States) does not support Digital T1 traffic, right now it is only for WAN connectivity and VoIP trunks.

I think this will be added later, but for now if you want a T1 for local lines, you will have to go with the 403,6,or12 with the T1 interface.

RE: small office

Thanks guys.....this makes things clearer. I will have to do some more research.

RE: small office

At several small offices I am using PRI circuits provisioned with 8 - 16 voice channels with the remaining channels used for internet connectivity providing a VPN connection to our corporate office. This has turned out to be a very cost effective solution (usually $600 - $800 monthly), and still gives me all of the features of PRI (DID's, etc).

RE: small office

You're paying that much for PRI? Where are you geographically located? My company is paying around $400/month and I thought that was average for the U.S.

RE: small office

Primarily in the SouthEast and MidWest. This seems to be standard pricing from local telcos (SBC and BellSouth) for PRI, DID's, mixed-use with 512k to internet. Thet are providing the drop and insert mux.

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