Is there any way or any calculation / formula exist with regard to calculating how many DSP resources are needed.While Planning I am getting confused at different level. i.e
Router( assume) 3845 has some DSP resources; 6500 - CMM module also has DSP resources;Cisco Call Manager has DSP resources.IP phones has DSP in it .. What's the best practice with regard to calculating DSP and planning it at Enterprise level( let say 15K userbase)
Thanks in Advance..
Try the DSP calculator under this link:
I was not able to calculate exactly as per the link..There are lot of parameter which needs to be filled in there.. Moreover is it wise to tell that the attached doc is the best way to calculate...!!! It will be great if you can share some case study from your past experience or some sample of calculation..
Thanks and regards,
Hi Mani, you should take another look to the DSP tool, it's very useful when you know how it works, I always use it.
You don't need to fill all the parameters, only those that are interesting for you.
First you have to select the router model and the IOS and the page appears next is for the calls. For instance, if you want to have 30 simultaneous calls you'll need a E1 and the tool is going to tell yo the DSPs needed. After you have the DSPs for the calls, the next screen is about the resources for "conference and transcoding".
If need to know more about resources, see the srnd guide at:
sorry but I am still having trouble with using this tool:-(.. I am not able to see any option for selection of PVDM2 modules.. May be for me this tool is too new:-) to use.
Hi Mani, you don't need to select the PVDM2 modules the tool is going to tell you this information.
For instance, you can select a cisco2801 with an E1 interface and say that you need 30 simultaneous calls, the tool is going to tell you need the next requeriments:
one PVDM2-32 or two PVDM2-16
It's telling you that you'll need 2 DSPs,and this is cover with one PVDM2-32 or two PVDM2-16
So, this tool is going to give you the numbers of DSPs and the PVDM2 modules you need.
Pls, rate if useful.
Engage a Cisco Unified Telephony partner to do this for you?
If you have 15,000 phones you can't do this without help...
I do agree with your response of engaging a Cisco Unified Telephony Partner but isn't it a foolish thing that if I have the number with me given by that partner and I don't know whether it is optimized one or simply selling more boxes/module....One should always know the basic and then only can justify the expenses...
Sorry if it sound harsh...
With best regards,
The values given in the DSP calculator should give you the most accurate estimate of the resources you are going to need for a given volume of required voice resources. The best part of engaging the partner is sharing their experience of the "when things go wrong" times when even with all the right parts and pieces you still get bit by the "gotchas".
The partners have run into it before and can offer a lot of advice on how to workaround the issue from experience in the field the customer may or may not have.
Justifying the expenses can be much easier if the partner helps you accurately access your DSP resources in the first place.