Neels Hofmeyr has submitted this change and it was merged. Change subject: mncc.adoc: clarify MNCC_BRIDGE, with future outlook ......................................................................
mncc.adoc: clarify MNCC_BRIDGE, with future outlook Change-Id: Ic71a83d71f2da87e1066fcc060b2b942643eddbc --- M common/chapters/mncc.adoc 1 file changed, 14 insertions(+), 2 deletions(-) Approvals: Harald Welte: Looks good to me, approved Jenkins Builder: Verified diff --git a/common/chapters/mncc.adoc b/common/chapters/mncc.adoc index 74ca6cf..77579a5 100644 --- a/common/chapters/mncc.adoc +++ b/common/chapters/mncc.adoc @@ -131,8 +131,20 @@ Requests that the TCH (voice) channels of two calls shall be inter-connected. This is the old-fashioned way of using MNCC, -primarily required for circuit-switched BTSs whose TRAU frames are -received via an E1 interface card on the {program-name} machine. +historically required for circuit-switched BTSs whose TRAU frames are +received via an E1 interface card, and works only when the TCH channel types +match. + +NOTE: Internal MNCC uses MNCC_BRIDGE to connect calls directly between +connected BTSs or RNCs, in effect disallowing calls between mismatching TCH +types and forcing all BTSs to be configured with exactly one TCH type and +codec. This is a limitation that will probably remain for the old OsmoNITB. For +the new OsmoMSC, the MNCC_BRIDGE command will instruct the separate OsmoMGW to +bridge calls, which will be able to handle transcoding between different TCH as +well as 3G (IuUP) payloads (but note: not yet implemented at the time of +writing this). Hence an external MNCC may decide to bridge calls directly +between BTSs or RNCs that both are internal to the OsmoMSC, for optimization +reasons. ==== MNCC_FRAME_RECV -- To view, visit https://gerrit.osmocom.org/4103 To unsubscribe, visit https://gerrit.osmocom.org/settings Gerrit-MessageType: merged Gerrit-Change-Id: Ic71a83d71f2da87e1066fcc060b2b942643eddbc Gerrit-PatchSet: 1 Gerrit-Project: osmo-gsm-manuals Gerrit-Branch: master Gerrit-Owner: Neels Hofmeyr <nhofm...@sysmocom.de> Gerrit-Reviewer: Harald Welte <lafo...@gnumonks.org> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: Neels Hofmeyr <nhofm...@sysmocom.de>