VOLGA Forum Publishes Stage 1 Specification for CS Voice over LTE

Not too long ago I reported on the foundation of the VOLGA (Voice Over LTE via Generic Access) Forum, which, as the abbreviation implies, wants to specify and implement a pragmatic approach for using the current circuit switched voice solution can over LTE. Looks like they have been quick to start their work, as the Stage 1 document for the proposed service is now already available on their website. Stage 1 is the first of 3 steps to describe a service from the basic concept (stage 1) to methods and procedures (stage 2) to the fine details including composition of messages (stage 3). Beyond what's already been written in 3GPP TR 23.879, I found the following interesting details:

  • The interface between the Volga Access Controller can be either A (GSM) or Iu (UMTS), in either their tradition variant or over IP. So if IP is selected the VOLGA solution is end to end (compare also to my R4 MSC post).
  • Transcoding Free Operation (TFO) shall be supported
  • H.324M for Video Calls shall be supported (great, completely forgot about that)

So, as you can see, quite some interesting details in the document, despite only being a stage 1 document.

Can't wait to see stage 2 and stage 3. Congrats to the VOLGA forum for the swift action!