MCM "deal" with the military posts in DCSA. Otherwise how would military bods get posted in to them?
Simple fact of life. ALL postings are carried out by MCM Div, ergo, if a Signals capbadge is in the slot, then MCM div dealt with it at some point.
There is a webpage on the Corps Intraweb site that will tell you all the potential slots in the various units tied to the Corps.
There are also various other tables that tell you of slots that you can fill that aren't Royal Signals only. ie RQMS at Pirbright or something, this would include the various Joint jobs knocking around.
Simply find one that matchs your CEQ and rank, and interests obviously.
Points to note, they may not be named DCSA. It could be 699 Tp or similar but it is merely the military bit of that particular DCSA. So a bit of research may be needed. Failing that phone the units you are interested in and ask if there is a slot for you.
Tell your chain of command the posting you want, and they may tell mcm what you want. Put on your PPP or whatevr it is called, where you roughly wnat to go.
DCSA became DGISS, part of DE&S, about two years ago.
As chocolate_frog mentioned Glasgow deal with all the posting to this organisation.
With regards to availability of posts it all depends on your CEQ, if you are an Inst Tech then you can forget about Gib, Cyprus or Germany as most of these posts are due to be disestablished within the next 18 months as part of the introduction of the Managed Site Connectivity program.
For all those that say DCSA does not exist I AM CURRENTLY POSTED THERE!!! (Thought it was a bit quiet)
In JHQ I am one of only 2 Army within the unit, the rest is civil servants and RAF, all the work is being contracted out and everybody is losing their job or jumping ship meaning more work for the few of us left.
As for a posting, not a chance. Once posted out the LSN is being closed until everyone comes under contract (civvies not military) or has left of own accord.
The only exception is in SCIDA and I have the only military post so you can't have it!