Take into account Marker bit when patching RTP stream
On a deployed osmo-mgw with RTP traffic coming from a thirdparty
RTP source, it was usual to see log messages like following one from
time to time:
"The input timestamp has an alignment error of 159 on SSRC"
Doing a quick traffic analysis showed that the above mentioned RTP
source was generating traffic from time to time containing RTP packets
with the Marker (M) bit.
Those messages were logged because the verification & patching funcions
in osmo-mgw were not Marker-bit aware. Hence, this patch implements
support for Marker bit when handling RTP packets.
The Marker bit is usually used as a start of a talkspurt, and has to be
considered a syncrhonization point, where timestamp and relation to real
time don't need to match with last received RTP packet in the stream.
Related: SYS#5498
Change-Id: I1fb449eda49e82607649122b9b9d983a9e5983fa
diff --git a/include/osmocom/mgcp/mgcp_network.h b/include/osmocom/mgcp/mgcp_network.h
index 75b342d..d6d90dd 100644
--- a/include/osmocom/mgcp/mgcp_network.h
+++ b/include/osmocom/mgcp/mgcp_network.h
@@ -176,4 +176,4 @@
/* internal RTP Annex A counting */
void mgcp_rtp_annex_count(const struct mgcp_endpoint *endp, struct mgcp_rtp_state *state,
const uint16_t seq, const int32_t transit,
- const uint32_t ssrc);
+ const uint32_t ssrc, const bool marker_bit);