laforge has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-gsm-manuals/+/32005 ) Change subject: chapters/cell-broadcast: Bring up-to-date with reality ...................................................................... chapters/cell-broadcast: Bring up-to-date with reality This chapter was written at a time where OsmoCBC and the related BSC support didn't exist yet. Change-Id: If02adf2f9e7beeb7f238ab1c3aa74e8c0155db2b --- M common/chapters/cell-broadcast.adoc 1 file changed, 32 insertions(+), 26 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-gsm-manuals refs/changes/05/32005/1 diff --git a/common/chapters/cell-broadcast.adoc b/common/chapters/cell-broadcast.adoc index 842e8d1..c1d9581 100644 --- a/common/chapters/cell-broadcast.adoc +++ b/common/chapters/cell-broadcast.adoc @@ -3,7 +3,7 @@ Normally, all user plane data in GSM/GPRS networks are sent in point-to-point channels from the network to the user. Those are called -"dedicated" radio channels which exist between the network and one +_dedicated_ radio channels which exist between the network and one given phone/subscriber at a time. Cell Broadcast is an exception to that rule. It permits user data @@ -35,39 +35,33 @@ === Osmocom Cell Broadcast support -* OsmoBTS implements the "SMS BROADCAST COMMAND" Message in RSL - according to Section 8.5.8 of 3GPP TS 08.58 -* OsmoNITB and OsmoBSC implement a VTY command - `bts <0-255> smscb-command <1-4> HEXSTRING` to send a given hex-formatted cell - broadcast message to a specified BTS +* OsmoBTS implements the `SMS BROADCAST COMMAND` Message in A-bis RSL + according to Section 8.5.8 of 3GPP TS 48.058 +* low-level testing/debugging features +** OsmoNITB and OsmoBSC implement a VTY command + `bts <0-255> smscb-command <1-4> HEXSTRING` to send a given hex-formatted cell + broadcast message to a specified BTS. This can be used for low-level debugging +* proper 3GPP-specified CBS/PWS elements and protocols +** OsmoBSC supports routing and distribution of CBS and warning messages +** OsmoBSC implements the BSC-CBC interface using the CBSP protocol +** OsmoCBC implements the central function of a _Cell Broadcast Centre_, + receiving cell broadcast and warning messages from external entities + via a REST based HTTP interface, and distributing it throughout the + cellular network. +** OsmoCBC implements the BSC-CBC interface using the CBSP protocol (for + 2G/GSM RAN) +** OsmoCBC implements the MME-CBC interface using the SBcAP protocol (for + 4G/LTE RAN) + [mscgen] ---- include::osmocom-cbs.msc[] ---- -==== What's missing - -What's missing (for production operation in larger networks) - -* mechanism to broadcast one (set of) cell broadcast messages from the - BSC to multiple/all BTSs, rather than one BTS individually -* OsmoBTS reporting of current CBCH load -* BSC scheduler scheduling multiple alternating sets of CBCH messages - based on the current CBCH load reported by BTS -* external interface from BSC to a Cell Broadcast Center (CBC), e.g. - according to 3GPP TS 48.049 -* an Osmocom implementation of the Cell Broadcast Center (OsmoCBC) - which can manage and distribute messages to multiple BSCs and which - has an external interface by which cell-broadcast can be entered - into the network - -If you would like to contribute in any of those areas (by means of -code or funding), please reach out to us any time. - === Message Structure -* Each message has a meximum of 15 pages +* Each message has a maximum of 15 pages * Each page is 82 bytes of data, resulting in 93 characters in GSM 7-bit default alphabet * Messages are broadcast on logical channels (more like an address) -- To view, visit https://gerrit.osmocom.org/c/osmo-gsm-manuals/+/32005 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-gsm-manuals Gerrit-Branch: master Gerrit-Change-Id: If02adf2f9e7beeb7f238ab1c3aa74e8c0155db2b Gerrit-Change-Number: 32005 Gerrit-PatchSet: 1 Gerrit-Owner: laforge &lt;laforge(a)osmocom.org&gt; Gerrit-MessageType: newchange