Cisco2611 question

[guefischer]

Hi, we want to start with some real VoIP-Tests. We need a connection to the PSTN. We have a PSTN-line (E1 - 30 channels) connected to a MAX 4000. Now we hope to get a 2611 with 2 E1 - one to PSTN and the second to the MAX 4000. I think/hope this will run!?

Because of our small budget - what is is the smallest

extendable configuration: CISCO 2611, CAB-ACE,

MEM2600-32U48D, MEM2600-8U16FS, NM-HDV+PVDM-12 (how much?)+VWIC-2MFT-E1+Software

Can we do a free configuration of the E1-Interfaces? On start we could do our job with 8 channels to PSTN and

4 to MAX 4000 - so one PVDM-12 would fit (mathematically) or need I 2 PVDM-12 or more?

Günther Fischer

[dgoodwin]

If you like, you can only purchase some of the PVDMs for now and add more later. Each PVDM-12 will support 12 channels of voice using medium complexity codec (e.g. G.711 or G.729) or 6 channels using high complexity (e.g. G.723.1).

If you want to get enough DSP capacity to support 60 calls then you can buy NM-HDV-2E1-60 bundle, or if you want to support 30 channels of voice but have 2 E1 connections then you can buy

NM-HDV

VWIC-2MFT-E1

PVDM-12 (quantity 3)

[guefischer]

Thank you, but a part answer to my question I miss:

Could I use one PVDM-12 and define 8 channels to one

E1 and 4 to another or have I to buy 2 PVDM-12 to

use 2 E1. And at last do you know about connecting the MAX 4000 to 2611 and then route some numbers to the MAX and other to VoIP from the PSTN side?

Thank you - Günther

[dgoodwin]

With a single PVDM-12 you can handle 12 channels of medium complexity voice (e.g. G.711) on the HDV module. It doesn't matter if those channels are split amongst multiple T1/E1 circuits or not.

As far as connecting one of the E1s to the MAX4000, you can certainly do this, but for modem calls I don't know that you will get the connect rates you are looking for, I think the most you may get is V.34 rates, not V.90 or V.92, since the DSPs in the 2600 would be responsible for carrying the modem tones.

[guefischer]

Thank you very much - my last short question: we need

Euro-ISDN data connections to the MAX so we could miss

the newer modem standards like V.90. I think this should work - right?

Günther

[selectica]

Günther,

I'm not 100% sure of what you are asking but it sounds like what you really want is drop-and-insert. This would allow you to connect 1 E1 from the PSTN and route 8 channels (or x number of the channels) to another E1 connected to your MAX 4000 without using any DSPs.

The 2611 is very limited since it only has one network module and you are already talking about connected 2 E1s. You should consider a 3640 or 3660 which has more capacity for connecting to PBXes, etc. Click on the URL below and carefully read the information as there are many restrictions and requirements.

http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t7/t1_mf_t6.htm

Multiplexed Voice and Data: 2-port T1/E1 VWICs can provide Drop-and-Insert multiplexing services with integrated DSU/CSUs. For example, when used with a Digital T1 Packet Voice Trunk Network Module, Drop and Insert allows you to take 64Kb DS0 channels from one T1 and digitally cross-connect them to 64Kb DS0 channels on another T1. Drop and Insert, sometimes called Time-Division Multiplexing (TDM) Cross-Connect, uses circuit switching and does not use the digital signal processors (DSPs) that VoIP technology employs.

Hope this helps.

Edward Munro

Network Engineer

Selectica, Inc.

emunro@selectica.com

[guefischer]

More about what I want: We have now a MAX4000 on a PSTN line E1 (30 channel) with a calling number like 037136704 and the are 1000 Subnumbers I didn't need for now. To start with a Testequipment for VoIP we want to use a 2611 and we hope we could put the 2611 to this PSTN line and the MAX4000 behind the 2611. If there

come a call to 03713670400 it should go to the MAX all

other as VoIP into the Ethernet. And all calls from the MAX should go to the PSTN.

Could the 2611 do that?