Early offer requires media resources Delayed offer does not require it
SIP Early Offer Support over Unified CM SIP Trunks SIP negotiates media exchange by means of the Session Description Protocol (SDP), where one side offers a set of capabilities to which the other side answers, thus converging on a set of media characteristics. SIP allows the initial offer to be sent either by the caller in the initial INVITE message (Early Offer) or, if the caller chooses not to, the called party can send the initial offer in the first reliable response (Delayed Offer). By default, Unified CM SIP trunks send the INVITE without an initial offer (Delayed Offer). In general SIP Delayed Offer is preferred for Unified CM SIP trunks because MTPs are not needed to establish a Delayed Offer call for voice, video, or encrypted media. If SIP Early Offer is desired, Unified CM has two configurable options to enable a SIP trunk to send the offer in the INVITE: •Media Termination Point Required<http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/trunks.html#wp1123292> •Early Offer Support for Voice and Video Calls (Insert MTP If Needed)<http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/trunks.html#wp1123822> Media Termination Point Required Enabling the *Media Termination Point Required* option on the SIP trunk assigns an MTP from the trunk's media resources group (MRG) to every outbound call. (See Figure 14-3<http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/trunks.html#wp1123264>.) This statically assigned MTP supports only the G.711 or G.729 codecs, thus limiting media to voice calls only. Figure 14-3 SIP Early Offer with Media Termination Point Required http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/8x/trunks.html#wp1123289 On Sun, May 12, 2013 at 9:24 AM, Ben John <benjoh...@hotmail.com> wrote: > Hello All, > when configuring SIP Delay Offer do we have to configure MRG for MTP ? In > one of IPExpert lab work book i have seen them configuring MRG for Early > Offer. Please advise > > Ben > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com >
_______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
