Review at https://gerrit.osmocom.org/5230
common: bts: dyn ts: explain dyn_ts_allow_tch_f from OsmoBSC viewpoint Change-Id: If9425b16216f353515890a7b2de8590bdfa1ff38 --- M common/chapters/bts.adoc 1 file changed, 14 insertions(+), 3 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-gsm-manuals refs/changes/30/5230/1 diff --git a/common/chapters/bts.adoc b/common/chapters/bts.adoc index b8d9f1b..116b69d 100644 --- a/common/chapters/bts.adoc +++ b/common/chapters/bts.adoc @@ -317,9 +317,20 @@ BTS models supporting this timeslot kind are shown in <<dyn_ts_compat>>. -NOTE: At the time of writing, OsmoNITB disables TCH/F on this timeslot type due -to transcoding limitations. Operation of OsmoBSC with a third-party MSC is not -affected by this limitation. See https://osmocom.org/issues/1778. +In the lack of transcoding capabilities, this timeslot type may cause +mismatching codecs to be selected for two parties of the same call, which would +cause call routing to fail ("`Cannot patch through call with different channel +types: local = TCH_F, remote = TCH_H`"). A workaround is to disable TCH/F on +this timeslot type, i.e. to allow only TCH/H. To disable TCH/F on Osmocom +style dynamic timeslots, use a configuration of + +---- +network + dyn_ts_allow_tch_f 0 +---- + +In OsmoNITB, disabling TCH/F on Osmocom dynamic timeslots is the default. In +OsmoBSC, the default is to allow both. ==== ip.access Style Dynamic Timeslots (TCH/F_PDCH) -- To view, visit https://gerrit.osmocom.org/5230 To unsubscribe, visit https://gerrit.osmocom.org/settings Gerrit-MessageType: newchange Gerrit-Change-Id: If9425b16216f353515890a7b2de8590bdfa1ff38 Gerrit-PatchSet: 1 Gerrit-Project: osmo-gsm-manuals Gerrit-Branch: master Gerrit-Owner: Neels Hofmeyr <nhofm...@sysmocom.de>