analog phones and centralized ipt deployment

[sarahr202]

Hi everybody.

Please consider the following scenario of centralised ip telephony deployment.

ip phone-1---sw-----Cisco call manager-------wan--------------Voice-gateway------------analog phone1

                             |                                                                                     |

                             |                                                                                     |

                           ip phone 2                                                            analog phone2

The above diagram shows a centralized ipt( ip telephony deployment) .  Let say analog phone1 wants to dial analog phone 2. My question is which device will provide dial tone to analog phone1 ? Is it voice gateway or cisco call manger in the above set up?

thanks and have a great weekend.

[Aaron Harrison · Accepted solution]

Hi

That would be provided by the analogue gateway - in as much as the analogue port on the gateway generates the tone. It may be controlled by CUCM - i.e. CUCM tells it to send dial tone, so it does. It's not a tone that is generated on the CUCM server and send over as an RTP stream...

Aaron

[sarahr202]

Thanks Aaron.

so with analog phones connected to a voice gateway we have two options:

1) configure voice gateway to generate and provide dial tone to connected analog phone. In this case there  CUCM has no role. Voice gateway simply provides dial tone when it senses a off -hook condition  on its analog interface.

2) CUCM dictates voice gateway when to generate dial done and when to send it over its analog interface .

Is my understanding correct?

Thanks and have a great weekend.

[Aaron Harrison · Accepted solution]

Hi

More or less, yes. If the gateway is just running h.323 or SIP then the dial tone and all other signalling is controlled locally.

If it's bound to MGCP (i.e. for CUCM) or STCAPP (SCCP, for CUCM or CME) then it will be at least partially controlled by the call-agent.

Aaron

[sarahr202]

Hi Aaron

Analog phone1-----voice gateway----PSTSN---analog phone2

If it's bound to MGCP (i.e. for CUCM) or STCAPP (SCCP, for CUCM or CME) then it will be at least partially controlled by the call-agent

Keeping in mind the above, assume voice gateway is running STCAPP, now we need to have call agent which then partially control voice gateway. 

Am i correct?

When we say call agent partially control voice gateway above, What exactly call agent is partially controlling above?

thanks and have a great weekend.