183 - No Connection Information (c) in RTP relay mode

vaclav_prokes · Post by **vaclav_prokes** » Sat Nov 19, 2016 2:47 am

1. Brekeke Product Name and Version:
3.6.3.0/454

2. Java version:
1.8.0_111

3. OS type and the version:
Windows 2003 x64

4. UA (phone), gateway or other hardware/software involved:
BridgeVoice carried

5. Your problem:
Brekeke SIP server instead for replacing IP Connection Information (c) SDP header completly removes Connection Information (c). There is no media information IP address.

Incoming SDP
Session Description Protocol
Session Description Protocol Version (v): 0
Owner/Creator, Session Id (o): iMax_SS 3550557704 3550557705 IN IP4 204.15.169.95
Session Name (s): iMax_SS
Connection Information (c): IN IP4 204.15.169.95
Time Description, active time (t): 0 0
Media Description, name and address (m): audio 30236 RTP/AVP 8 0 18 101
Media Attribute (a): rtpmap:8 PCMA/8000
Media Attribute (a): rtpmap:0 PCMU/8000
Media Attribute (a): rtpmap:18 G729/8000
Media Attribute (a): fmtp:18 annexb=no
Media Attribute (a): rtpmap:101 telephone-event/8000
Media Attribute (a): fmtp:101 0-15
Media Attribute (a): sqn: 0
Media Attribute (a): cdsc: 1 audio RTP/AVP 8 0 18 101
Media Attribute (a): cpar: a=rtpmap:8 PCMA/8000
Media Attribute (a): cpar: a=fmtp:8 vad=no
Media Attribute (a): cpar: a=rtpmap:0 PCMU/8000
Media Attribute (a): cpar: a=fmtp:0 vad=no
Media Attribute (a): cpar: a=rtpmap:18 G729/8000
Media Attribute (a): cpar: a=fmtp:18 annexb=no
Media Attribute (a): cpar: a=rtpmap:101 telephone-event/8000
Media Attribute (a): cpar: a=fmtp:101 0-15
Media Attribute (a): cdsc: 5 image udptl t38
Media Attribute (a): sendrecv
Media Attribute (a): ptime:20

Outgoing SDP
Session Description Protocol
Session Description Protocol Version (v): 0
Owner/Creator, Session Id (o): iMax_SS 3550557704 3550557705 IN IP4 10.10.0.5
Time Description, active time (t): 0 0
Media Description, name and address (m): audio 10222 RTP/AVP 8 0 18 101
Media Attribute (a): rtpmap:8 PCMA/8000
Media Attribute (a): rtpmap:0 PCMU/8000
Media Attribute (a): rtpmap:18 G729/8000
Media Attribute (a): fmtp:18 annexb=no
Media Attribute (a): rtpmap:101 telephone-event/8000
Media Attribute (a): fmtp:101 0-15
Media Attribute (a): sqn: 0
Media Attribute (a): cdsc: 1 audio RTP/AVP 8 0 18 101
Media Attribute (a): cpar: a=rtpmap:8 PCMA/8000
Media Attribute (a): cpar: a=fmtp:8 vad=no
Media Attribute (a): cpar: a=rtpmap:0 PCMU/8000
Media Attribute (a): cpar: a=fmtp:0 vad=no
Media Attribute (a): cpar: a=rtpmap:18 G729/8000
Media Attribute (a): cpar: a=fmtp:18 annexb=no
Media Attribute (a): cpar: a=rtpmap:101 telephone-event/8000
Media Attribute (a): cpar: a=fmtp:101 0-15
Media Attribute (a): cdsc: 5 image udptl t38
Media Attribute (a): sendrecv
Media Attribute (a): ptime:20

Matching Patterns
$request="^INVITE"
$addr="10.10.0.50"
To="sip:sip-usa-bri-pl:(.+)@"
From="sip:(.+)@"

Deploy Patterns
$target="204.15.169.92"
$auth="false"
To="\"\"<sip:1111%1@204.15.169.92>"
From="\"\"<sip:%2@185.164.68.20>"
P-Asserted-Identity="<sip:%{$getSIPuser(P-Asserted-Identity)}@185.164.68.20>"
$ifsrc="10.10.0.5"
$ifdst="185.164.68.20"

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 10:18 am

Can you paste the original SDP content here?

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 10:38 am

ambrosio wrote:Can you paste the original SDP content here?

Incoming SDP
Session Description Protocol
Session Description Protocol Version (v): 0
Owner/Creator, Session Id (o): iMax_SS 3550557704 3550557705 IN IP4 204.15.169.95
Session Name (s): iMax_SS
Connection Information (c): IN IP4 204.15.169.95
Time Description, active time (t): 0 0
Media Description, name and address (m): audio 30236 RTP/AVP 8 0 18 101
Media Attribute (a): rtpmap:8 PCMA/8000
Media Attribute (a): rtpmap:0 PCMU/8000
Media Attribute (a): rtpmap:18 G729/8000
Media Attribute (a): fmtp:18 annexb=no
Media Attribute (a): rtpmap:101 telephone-event/8000
Media Attribute (a): fmtp:101 0-15
Media Attribute (a): sqn: 0
Media Attribute (a): cdsc: 1 audio RTP/AVP 8 0 18 101
Media Attribute (a): cpar: a=rtpmap:8 PCMA/8000
Media Attribute (a): cpar: a=fmtp:8 vad=no
Media Attribute (a): cpar: a=rtpmap:0 PCMU/8000
Media Attribute (a): cpar: a=fmtp:0 vad=no
Media Attribute (a): cpar: a=rtpmap:18 G729/8000
Media Attribute (a): cpar: a=fmtp:18 annexb=no
Media Attribute (a): cpar: a=rtpmap:101 telephone-event/8000
Media Attribute (a): cpar: a=fmtp:101 0-15
Media Attribute (a): cdsc: 5 image udptl t38
Media Attribute (a): sendrecv
Media Attribute (a): ptime:20

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 11:07 am

vaclav_prokes,
It is Wireshark's expression of SDP not original raw data..

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 11:16 am

Does the issue still happen even if you don't use RTP-relay?

Does the same issue happen even if you make a call from another SIP client or VoIP service?

It seems "Session Name (s): iMax_SS " is also missing.

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 11:40 am

ambrosio wrote:Does the issue still happen even if you don't use RTP-relay?

Does the same issue happen even if you make a call from another SIP client or VoIP service?

It seems "Session Name (s): iMax_SS " is also missing.

The problem is still happening. I have tried different devices to call to this partner. Unfortunately I have to use RTP relay in this case.

Here is whole PCAP available http://www.uschovna.cz/en/zasilka/LFWWEI39VCWB8NXJ-YIP/

Thank you

Vaclav

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 11:44 am

Vaclav
I've downloaded it. So you can remove it now.

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 12:00 pm

Vaclav,
Is it the pcap you have SDP issue??

I can see "c=" line in the outgoing SDP which points 185.164.x.x what you defined.

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 12:12 pm

ambrosio wrote:Vaclav,
Is it the pcap you have SDP issue??

I can see "c=" line in the outgoing SDP which points 185.164.x.x what you defined.

My BS have two interfaces. The packets in PCAP are not in correct order. Internal 10.10.0.5 and external 185.164.68.20.
You have to order it by time.

The original SDP packet no 9 is coming from 204.15.169.92 to 185.164.68.20 there is still (c) IP address to BS

It is processed by BS and outgoing packet

Outgoing packet no 5 is going fom BS 10.10.0.5 to Aculab switch 10.10.0.50. This packet is missing (c) information.

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 1:20 pm

The reason of the issue is the packet size.

The "183 Session Progress" packet sent from 204.15.169.92 was fragmented and these fragmented frames were delayed .
The fragmentation happened because the packet size exceeded 1500 bytes.
The wireshark indicates that the packet size is 1520 bytes.

As you know, most network entities limit the MTU (Maximum
transmission unit) 1500 bytes.

To avoid the issue:
- Expand the MTU size at OS and network entities
or
- Reduce the size of SIP packet
or
- Use TCP or TLS

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 2:39 pm

ambrosio wrote:The reason of the issue is the packet size.

The "183 Session Progress" packet sent from 204.15.169.92 was fragmented and these fragmented frames were delayed .
The fragmentation happened because the packet size exceeded 1500 bytes.
The wireshark indicates that the packet size is 1520 bytes.

As you know, most network entities limit the MTU (Maximum
transmission unit) 1500 bytes.

To avoid the issue:
- Expand the MTU size at OS and network entities
or
- Reduce the size of SIP packet
or
- Use TCP or TLS

Hi, this must be an issue of BS. I have lot of fragmented INVITE's ant it works.Why it should not work with differnet messages ?
Ny the way the fragment arrived 0,000016 s after the main part.

ambrosio · Post by **ambrosio** » Wed Nov 23, 2016 4:09 pm

The packet was corrupted before it reached the SIP Server.
Other SIP packets less than 1500 bytes are OK.

Expand OS's MTU but I recommend you use TCP instead of UDP because other network entities such as router will also limit the size.

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 7:18 pm

ambrosio wrote:The packet was corrupted before it reached the SIP Server.
Other SIP packets less than 1500 bytes are OK.

Expand OS's MTU but I recommend you use TCP instead of UDP because other network entities such as router will also limit the size.

Hi, have look at new dump. I have applied net.sip.via.multiple=false
The packet is now under 1500 but the result is the same.

http://www.uschovna.cz/en/zasilka/LFIBVHX49KUNIAS8-KGL/

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 8:01 pm

Here is dump from BS.
It seems to me BS is not parsing the header correctly.

Please find the link to BS log file.
Parameters (s) and (c) are not correctly parsed from (o).
There are some characters

When you open the file just for view, the s,c,o are on separate lines.
When you do edit file you will see that they are on one line

vaclav_prokes · Post by **vaclav_prokes** » Wed Nov 23, 2016 8:01 pm

http://www.uschovna.cz/en/zasilka/LFVJIH6FZHFCALPH-JMD/