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New Member

Implemeting Unified Comm.s on multibranch with support of PBX

Hi, Our customer wants to implement Unified Communications solutions for multi branch. It has 20 branches with each of 15 users in one city. But I don't know which infrastructure model, switches and end user products are suitable for this situation? Can anyone help me?

Hall of Fame Super Gold

Re: Implemeting Unified Comm.s on multibranch with support of PB


It really depends on budget in this case.

If you are tight, suggest you go with the central model in which a possibly redundant CM at main site handles all the phones.

Switch doesn't really matter, that is if you can have it with poe will be better.

Else you couls insyall as CU520 w/ 16 users support in each branch, this will make each site indipendant, however will be more expensive and have an higher support demand.

New Member

Re: Implemeting Unified Comm.s on multibranch with support of PB


Thanks for your reply. What models are redundant CM? How many users it can handle if headquarter has 200 users and plus other branches?

Is it possible to combine these 2 ways together central model and some CU520 at some branches?

Hall of Fame Super Gold

Re: Implemeting Unified Comm.s on multibranch with support of PB

Hi, all CM models are redundant (cluster), you buy a minimum of two servers for the redundancy. You need to get in touch with cisco or a reputable partner to get an idea of model and prices, however for example the mcs-7816 is the smaller rackmount unit and would support 200 user perfectly even without redundancy.

Then if you can put an intelligent device at the branches too, this will give you the so called SRST that if the line to hub goes down, phones can still be used locally and if you have a pots line locally, it will be used. This line or lines is also always the one used for emergency calls.

However, for SRTS, you won't use the CM520 but a real router with voice, going fro the 1861 for 8 users, or the 2801 up to 24 users. The device can also termiate you WAN/MAN connections, do firewall, VPN and all the things a router does.

These are the architecture alternatives in extreme simplification. If you can read the

it has all the details. Note, implementation for 20 branches is not trivial and requires experience, time and a lot of attention to details. It is highly recommended you choose an experienced certified cisco partner if it is your first IPT project.