100% Encryption limitation on CUCM 8/9 ??

[nishjhony]

Hi Team,

I would like to understand the possible limitation for 100% encryption of IP Phones registered in CUCM 8/9.

I heard that 100% encryption will bring down the size of the cluster. For eg: If we have 30000 IP Phones without encryption, after 100% encryption we can only have 25000 IP Phones registered to the CUCM cluster.

I would like to understand the possible reason for the above.

Licensing and bandwidth is not the reason I believe.

[Jaime Valencia]

Simply because the encryption procedure takes more CPU, and the amount of call control traffic generated is more than on a not encrypted deployment.

[nishjhony]

Hi Jaime,

Thanks for the reply. I really appreciate it.

Can you also please direct me to any document supporting this?

I need to prepare the deck and present it.

Thank You.

[nishjhony]

Hi Jaime,

After analysing your reply, my reply is you are speaking about the operation part (call control traffic). But my question is about the registration of IP Phone.

Yeah I agree that 100% encryption will make CPU over loaded during the operation. This can be considered as the second drawback of 100% encryption.

My question is will 100% encryption bring down the number of IP Phones regestering to the CUCM. If so what is the exact reason? Is there any Cisco document for this?

Thank You.

[Jaime Valencia]

Registration messages and keepalives are also encrypted.