Feature #1781

offer a dynamic TCH/H_PDCH pchan type

Added by neels over 2 years ago. Updated 4 months ago.

Target version:
Start date:
Due date:
% Done:


Spec Reference:


We now have these dynamic pchan types:

  • TCH/F_PDCH (PDCH ACT style)

It would be fairly trivial to add a dedicated TCH/H_PDCH type,
i.e. a TCH/F_TCH/H_PDCH (CHAN ACT style) that has TCH/F disabled.

Downsides: it adds a bit of code bloat (more switch cases...).

Benefits: Having this pchan type prevents phones from hogging a whole
TCH/F, theoretically doubling the capacity.


#1 Updated by neels over 2 years ago

A different way to allow dyn TS without TCH/F is in
if one adds a VTY command.

Of course it would be a far nicer user experience to have an actual TCH/H_PDCH pchan type.

#2 Updated by neels about 2 years ago

to be able to add a VTY command, would be helpful.
So far, in the 603 patch we set dyn_ts_allow_tch_f after reading the config.
#1140 would allow setting the default to false in osmo-nitb only, and reading the config later on.

#3 Updated by neels about 2 years ago

gerrit patch 1140 is now merged to master, so we could now add a VTY config for
osmo-nitb to allow/disallow TCH/F on dynamic TCH/F_TCH/H_PDCH timeslots.
(My attention is with the VLR though.)

#4 Updated by laforge about 1 year ago

  • Project changed from OpenBSC to OsmoBTS

#5 Updated by laforge 4 months ago

  • Assignee deleted (neels)

#6 Updated by neels 4 months ago

  • Status changed from New to Rejected

If we configure a pchan of TCH/F_TCH/H_PDCH and a codec-list of only half-rate codecs, we also obtain dynamic TS that will never be used for TCH/F.
Furthermore, if the codec-list features FR after the HR codecs, then we prefer to use TCH/H, but if unavailable use TCH/F, which is the same as above with a fallback to TCH/F.
Bottom line: this feature idea is not going to be implemented because the codec-list provides all useful flexibility already.

Also available in: Atom PDF

Add picture from clipboard (Maximum size: 48.8 MB)