how can I check my router for telephony-service?

[Samiullah Osman]

I have a cisco 3900 router, when I type telephony-service it dose`t work. can I use cisco 3900 for ip phones?

[Roger Kallberg]

I assume that you refer to using your router for CME, Call Manager Express? If so yes you can use a 3900 router. Please have a look at this document for details on how to setup CME. Cisco Unified Communications Manager Express System Administrator Guide 

[Samiullah Osman]

Thanks for replying me.

we have 12 cisco ip phones in office and I want to configure them. I can do it using packet tracer but those commands don`t work in my cisco router. commands like: telephony-service 

[Roger Kallberg]

Have you checked if you have enabled voice services on your router? These are Right To Use, but there is no actual check that the platform is licensed. For more information on this please see this document. Software Activation Configuration Guide, Cisco IOS Release 15M&T