I'm not familiar with Genband, but, I worked on Sonus when Global Crossing replaced their DSC DEX-600E's with Sonus VoIP switches.
Genband is alot of the former Nortel switch personnel. They took over support for the DMS-10, DMS-100, etc and replaced them with their softswitches, the C15 and C20 primarily.
I was just in Raleigh at their training and support facility for some translations training when the announcement was made. We were told that Genband is primarily in the Class 5 arena and that Sonus (who not long ago bought out Taqua and their softswitch), is in the Class 4 market. I for one, know that the big boys (C/L, ATT, Verizon) still have hundreds of DMS switches in service. Will be interesting to see how this plays out.
I'm about to visit their RTP location for a third time for training, I'll be attending their c15 Translations class this time around. Was your instructor Todd Hand?
And now they are "Ribbon"
Yes, Todd Hand was my instructor for 3 different C15 training sessions, including translations.