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IPT desgin question.


I have a secnario where at the HQ there will be some 70 IP Phones with CM. There are 30 branches connected to the HQ via an IP MPLS service provider VPN backbone. I need to have atleast one IP Phone in each of the branch.

My question is

1. Can I use the same CM at the HQ to provide call processing for all the 30 branch IP Phones.

2. Do i need to ask the service provider to make any changes on the CPE routers.

3. Assuming delay, jitter, bandwidth ( jst one call ) is not an issue on the link, can I simply plug 1 IP Phone at the branch and have the phone registered with the CM at the HQ.

4. Is it necessary to have voice enabled routers at the branch level too ?




Hall of Fame Super Silver

Re: IPT desgin question.

1. Definitely, it's called multiple site centrelized call processing design

2. I would recommand talking to the SP about your QoS markings as MPLS actually looks at the headers

3. Reconfigure the access layer switch switchports to include voice VLAN, create DHCP scope for the VLAN and add scope 150 that points to TFTP server (CCM), if you want to use static IP on the phone and you can hard code the TFTP IP. Then plug in the phone.

4. You will need voice enabled routers if the remote sites need access to local PSTN, usually that's the case, you make local calls via the local GW. This will require T1/E1/FXO ports on the router.


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