Unlike the IP-TDM-IP connectivity option, hairpinning requires that all media processing resources for a given call reside on a single TN2302AP or TN2602AP media processing circuit pack or a single G350 or G700 Media Gateway Voip Media Module. A hairpinned call is originally set up as an IP-TDM-IP call, but once the set-up process is complete, no TDM resources are required. However, resources on the Media Processing circuit pack or VoIP Media Module are required for the duration of the call. A Media Processing circuit pack and a VoIP Media Module each house an on-board Central Processing Unit (CPU) and Digital Signal Processors (DSPs).
A shuffled call relinquishes all TDM and media processing resources after call set-up. Therefore, the media stream of a shuffled call traverses only an IP network. This is the most commonly used mode of connectivity between two IP endpoints in the same system.