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New Member

MTP ??


i want please from someone to clarify the concept behind MTP and where it is usefull and where it is used

i read that (MTPs are used to extend supplementary services to H.323 endpoints that do not support empty

capabilities sets. When needed, an MTP is allocated and connected into a call on behalf of an

H.323 endpoint. When an MTP is inserted into the RTP streams, the media streaming are

connected between the MTP and H323 device, where the RTP stream is not torn down for the

duration of the call. The media streaming connected to the other side of the MTP can be

connected and torn down as needed to implement features such as hold, transfer, and so forth)

and there are HW based MTPs and SW based MTPs !!!

so can someone please explain more what is meant by the above paragraph

and where do we actually need to implement MTPs

and if all end points are sccp do we need to implement MTP as well?

appreciate ur help and thanks

New Member

Re: MTP ??


I'm studying CIPT and I was exactly in same the same case than you about MTP, sometimes it can be very very difficult to understand what the autor meant because they don't give any example at all. Last week I manage to find an explanation :

for example when I user or a phone receive a call that come from an H323 gateway,, it's not possible to transfer the call to another phone because some old version of H323 gateway can't handle it.

so with MTP, when the user press the transfer button, the call is caught automatically by MTP, so with MTP you can stock the active call in memory while the user is doing the transfer. this is true with other services also HOLD ...., new versions of H323 don't need MTP, as they support natively this service.

So we can see MTP as a little "room" when calls are parked while we are handling or using a feature such as call HOLD, TRANSFER ...

as far I know this concern only H323, not sccp ... could someone confirm ??

hope this help.


Re: MTP ??

You are right, its only required for h323 based devices that doesnt support empty capabilities set. The server itself supports software based MTP for integrations such as an Intercluster trunk to another callmanager, ICT to CME systems etc. You may want to check the MTP option under the trunk setup to enable supplementary services such as hold, transfer etc.

When any other codec other than g711 is involved, Cisco's software based MTp services on callmanager will not help. For g729 support, you will have to rely on a hardware based MTP which is nothing but a transcoder.