SCCP vs. SIP for new phones & CME sanity check

[b.henshaw]

We're looking at implementing a CallManager Express based solution on a new 2801 router. I have two questions regarding this.

1. We have a choice of SCCP or SIP software for the IP phones (7912G & 7940G). I can't find much information on the practical difference between the two when used with CME. Can anyone provide input on what factors may make one choose a particular version over another? Obviously if we choose SCCP and want to move to a different call management solution later, we can change to the SIP software. Though it could be easier to start with the SIP firmware in the first place if it doesn't lack any features or support in CME 3.4.

2. We're looking at buying a particular bundle (for use in Australia) which includes a 2801 with the Advanced IP Security feature set, 24 CCME client licenses, AIM-VPN and PVDM2-8, plus a 2 port BRI VIC.

This will be used with 2x ISDN2 services and a 100 number indial range. The majority of call routing will be outgoing and ingoing via BRI.

Can anyone see any particular flaws in this plan? (other than that I need to buy some books and do some heavy reading rather than just trawling the Cisco site for documentation)

[peter.rowe]

The hardware bundle you mention sounds good, but you will be at the maximum amount of phones possible with a 2801, which in my opinion is not a good state of afairs! (plan for expansion from day 1 - it always happens!)

http://www.cisco.com/univercd/cc/td/doc/product/voice/its/cme34/cme34spc.htm

Also the SIP software is brand new to CME 3.4, so you will be in uncharted waters if you go for a pure SIP environment at this stage. I have tried upgrading but have been having a lot of BRI layer2 issues when upgrading the IOS on my 1760..

Whereas the SCCP CME is becoming more stable there are still a few issues with GroupPickup etc, but nothing that in my opinion is a showstopper.

hope this helps, if you go for SIP let me know how it goes!

[b.henshaw]

Thanks for the feedback. It sounds as though SCCP may be the way to go for the moment. We'll be developing this alongside our current POTS lines anyway, so we'll have time to see whether SCCP or SIP behaves better.

Although the bundle comes with the feature license for 24 phones (which is the maximum number the 2801 can handle, as you mentioned), we're only going to have 6 to start with, and two incoming BRI's. So that's a reasonable amount of room to move for us - capacity for 18 extra phones, and we won't be exceeding 8 channels (4 BRI's) any time soon so to go that far would only need another BRI VIC and potentially another PVDM card depending on conferencing and transcoding requirements.