[Freeswitch-users] RTP Wrong Timestamps and audio hiccups in conferencing output

Michael Jerris mike at jerris.com
Fri Sep 27 01:24:47 MSD 2013


This looks like its a timestamp rollover maybe.. in other places this happens, whats the timestamp before and after?

in this case, before: 32320, after: 480 (marker bit set).

Mike

On Sep 26, 2013, at 4:52 PM, D D <tru083 at yahoo.com> wrote:

> Hi,
> 
> I have an example of a wrong timestamp below.  It begins in packet 3563.  What do you think?
> 
> Thanks,
> David
> 
> 
> No.     Time            Source                src port Destination           dst port Protocol Info                                                            New Column
>    3505 13:39:29.130487 10.1.1.226            22776    10.1.1.1              18384    RTP      PT=ITU-T G.711 PCMU, SSRC=0x7D5DC9C, Seq=16396, Time=32000      214
> 
> Frame 3505: 214 bytes on wire (1712 bits), 214 bytes captured (1712 bits)
>     WTAP_ENCAP: 1
>     Arrival Time: Sep 24, 2013 13:39:29.130487000 CDT
>     [Time shift for this packet: 0.000000000 seconds]
>     Epoch Time: 1380047969.130487000 seconds
>     [Time delta from previous captured frame: 0.002441000 seconds]
>     [Time delta from previous displayed frame: 0.020005000 seconds]
>     [Time since reference or first frame: 30.185993000 seconds]
>     Frame Number: 3505
>     Frame Length: 214 bytes (1712 bits)
>     Capture Length: 214 bytes (1712 bits)
>     [Frame is marked: False]
>     [Frame is ignored: False]
>     [Protocols in frame: eth:ip:udp:rtp]
>     [Coloring Rule Name: UDP]
>     [Coloring Rule String: udp]
> Ethernet II, Src: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a), Dst: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>     Destination: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         Address: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Source: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         Address: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Type: IP (0x0800)
> Internet Protocol Version 4, Src: 10.1.1.226 (10.1.1.226), Dst: 10.1.1.1 (10.1.1.1)
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
>     Total Length: 200
>     Identification: 0x0000 (0)
>     Flags: 0x02 (Don't Fragment)
>         0... .... = Reserved bit: Not set
>         .1.. .... = Don't fragment: Set
>         ..0. .... = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 64
>     Protocol: UDP (17)
>     Header checksum: 0x2341 [correct]
>         [Good: True]
>         [Bad: False]
>     Source: 10.1.1.226 (10.1.1.226)
>     Destination: 10.1.1.1 (10.1.1.1)
> User Datagram Protocol, Src Port: 22776 (22776), Dst Port: 18384 (18384)
>     Source port: 22776 (22776)
>     Destination port: 18384 (18384)
>     Length: 180
>     Checksum: 0x17aa [validation disabled]
>         [Good Checksum: False]
>         [Bad Checksum: False]
> Real-Time Transport Protocol
>     [Stream setup by SDP (frame 2754)]
>         [Setup frame: 2754]
>         [Setup Method: SDP]
>     10.. .... = Version: RFC 1889 Version (2)
>     ..0. .... = Padding: False
>     ...0 .... = Extension: False
>     .... 0000 = Contributing source identifiers count: 0
>     0... .... = Marker: False
>     Payload type: ITU-T G.711 PCMU (0)
>     Sequence number: 16396
>     [Extended sequence number: 81932]
>     Timestamp: 32000
>     Synchronization Source identifier: 0x07d5dc9c (131456156)
>     Payload: ffeeebf2776c6c79f0ebee7d6d6b74f5ebedfb6f6b6ffbed...
> 
> No.     Time            Source                src port Destination           dst port Protocol Info                                                            New Column
>    3509 13:39:29.150492 10.1.1.226            22776    10.1.1.1              18384    RTP      PT=ITU-T G.711 PCMU, SSRC=0x7D5DC9C, Seq=16397, Time=32160      214
> 
> Frame 3509: 214 bytes on wire (1712 bits), 214 bytes captured (1712 bits)
>     WTAP_ENCAP: 1
>     Arrival Time: Sep 24, 2013 13:39:29.150492000 CDT
>     [Time shift for this packet: 0.000000000 seconds]
>     Epoch Time: 1380047969.150492000 seconds
>     [Time delta from previous captured frame: 0.002365000 seconds]
>     [Time delta from previous displayed frame: 0.020005000 seconds]
>     [Time since reference or first frame: 30.205998000 seconds]
>     Frame Number: 3509
>     Frame Length: 214 bytes (1712 bits)
>     Capture Length: 214 bytes (1712 bits)
>     [Frame is marked: False]
>     [Frame is ignored: False]
>     [Protocols in frame: eth:ip:udp:rtp]
>     [Coloring Rule Name: UDP]
>     [Coloring Rule String: udp]
> Ethernet II, Src: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a), Dst: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>     Destination: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         Address: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Source: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         Address: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Type: IP (0x0800)
> Internet Protocol Version 4, Src: 10.1.1.226 (10.1.1.226), Dst: 10.1.1.1 (10.1.1.1)
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
>     Total Length: 200
>     Identification: 0x0000 (0)
>     Flags: 0x02 (Don't Fragment)
>         0... .... = Reserved bit: Not set
>         .1.. .... = Don't fragment: Set
>         ..0. .... = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 64
>     Protocol: UDP (17)
>     Header checksum: 0x2341 [correct]
>         [Good: True]
>         [Bad: False]
>     Source: 10.1.1.226 (10.1.1.226)
>     Destination: 10.1.1.1 (10.1.1.1)
> User Datagram Protocol, Src Port: 22776 (22776), Dst Port: 18384 (18384)
>     Source port: 22776 (22776)
>     Destination port: 18384 (18384)
>     Length: 180
>     Checksum: 0x17aa [validation disabled]
>         [Good Checksum: False]
>         [Bad Checksum: False]
> Real-Time Transport Protocol
>     [Stream setup by SDP (frame 2754)]
>         [Setup frame: 2754]
>         [Setup Method: SDP]
>     10.. .... = Version: RFC 1889 Version (2)
>     ..0. .... = Padding: False
>     ...0 .... = Extension: False
>     .... 0000 = Contributing source identifiers count: 0
>     0... .... = Marker: False
>     Payload type: ITU-T G.711 PCMU (0)
>     Sequence number: 16397
>     [Extended sequence number: 81933]
>     Timestamp: 32160
>     Synchronization Source identifier: 0x07d5dc9c (131456156)
>     Payload: fff0edf4796e6e7af3edf17d6f6e76f7eeeffc726d72fcef...
> 
> No.     Time            Source                src port Destination           dst port Protocol Info                                                            New Column
>    3513 13:39:29.170502 10.1.1.226            22776    10.1.1.1              18384    RTP      PT=ITU-T G.711 PCMU, SSRC=0x7D5DC9C, Seq=16398, Time=32320      214
> 
> Frame 3513: 214 bytes on wire (1712 bits), 214 bytes captured (1712 bits)
>     WTAP_ENCAP: 1
>     Arrival Time: Sep 24, 2013 13:39:29.170502000 CDT
>     [Time shift for this packet: 0.000000000 seconds]
>     Epoch Time: 1380047969.170502000 seconds
>     [Time delta from previous captured frame: 0.002428000 seconds]
>     [Time delta from previous displayed frame: 0.020010000 seconds]
>     [Time since reference or first frame: 30.226008000 seconds]
>     Frame Number: 3513
>     Frame Length: 214 bytes (1712 bits)
>     Capture Length: 214 bytes (1712 bits)
>     [Frame is marked: False]
>     [Frame is ignored: False]
>     [Protocols in frame: eth:ip:udp:rtp]
>     [Coloring Rule Name: UDP]
>     [Coloring Rule String: udp]
> Ethernet II, Src: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a), Dst: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>     Destination: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         Address: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Source: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         Address: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Type: IP (0x0800)
> Internet Protocol Version 4, Src: 10.1.1.226 (10.1.1.226), Dst: 10.1.1.1 (10.1.1.1)
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
>     Total Length: 200
>     Identification: 0x0000 (0)
>     Flags: 0x02 (Don't Fragment)
>         0... .... = Reserved bit: Not set
>         .1.. .... = Don't fragment: Set
>         ..0. .... = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 64
>     Protocol: UDP (17)
>     Header checksum: 0x2341 [correct]
>         [Good: True]
>         [Bad: False]
>     Source: 10.1.1.226 (10.1.1.226)
>     Destination: 10.1.1.1 (10.1.1.1)
> User Datagram Protocol, Src Port: 22776 (22776), Dst Port: 18384 (18384)
>     Source port: 22776 (22776)
>     Destination port: 18384 (18384)
>     Length: 180
>     Checksum: 0x17aa [validation disabled]
>         [Good Checksum: False]
>         [Bad Checksum: False]
> Real-Time Transport Protocol
>     [Stream setup by SDP (frame 2754)]
>         [Setup frame: 2754]
>         [Setup Method: SDP]
>     10.. .... = Version: RFC 1889 Version (2)
>     ..0. .... = Padding: False
>     ...0 .... = Extension: False
>     .... 0000 = Contributing source identifiers count: 0
>     0... .... = Marker: False
>     Payload type: ITU-T G.711 PCMU (0)
>     Sequence number: 16398
>     [Extended sequence number: 81934]
>     Timestamp: 32320
>     Synchronization Source identifier: 0x07d5dc9c (131456156)
>     Payload: fff3eff77a71717bf6eff47e727078f9f0f2fd757075fdf2...
> 
> No.     Time            Source                src port Destination           dst port Protocol Info                                                            New Column
>    3563 13:39:29.490508 10.1.1.226            22776    10.1.1.1              18384    RTP      PT=ITU-T G.711 PCMU, SSRC=0x7D5DC9C, Seq=16399, Time=480, Mark  214
> 
> Frame 3563: 214 bytes on wire (1712 bits), 214 bytes captured (1712 bits)
>     WTAP_ENCAP: 1
>     Arrival Time: Sep 24, 2013 13:39:29.490508000 CDT
>     [Time shift for this packet: 0.000000000 seconds]
>     Epoch Time: 1380047969.490508000 seconds
>     [Time delta from previous captured frame: 0.002419000 seconds]
>     [Time delta from previous displayed frame: 0.320006000 seconds]
>     [Time since reference or first frame: 30.546014000 seconds]
>     Frame Number: 3563
>     Frame Length: 214 bytes (1712 bits)
>     Capture Length: 214 bytes (1712 bits)
>     [Frame is marked: False]
>     [Frame is ignored: False]
>     [Protocols in frame: eth:ip:udp:rtp]
>     [Coloring Rule Name: UDP]
>     [Coloring Rule String: udp]
> Ethernet II, Src: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a), Dst: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>     Destination: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         Address: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Source: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         Address: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Type: IP (0x0800)
> Internet Protocol Version 4, Src: 10.1.1.226 (10.1.1.226), Dst: 10.1.1.1 (10.1.1.1)
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
>     Total Length: 200
>     Identification: 0x0000 (0)
>     Flags: 0x02 (Don't Fragment)
>         0... .... = Reserved bit: Not set
>         .1.. .... = Don't fragment: Set
>         ..0. .... = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 64
>     Protocol: UDP (17)
>     Header checksum: 0x2341 [correct]
>         [Good: True]
>         [Bad: False]
>     Source: 10.1.1.226 (10.1.1.226)
>     Destination: 10.1.1.1 (10.1.1.1)
> User Datagram Protocol, Src Port: 22776 (22776), Dst Port: 18384 (18384)
>     Source port: 22776 (22776)
>     Destination port: 18384 (18384)
>     Length: 180
>     Checksum: 0x17aa [validation disabled]
>         [Good Checksum: False]
>         [Bad Checksum: False]
> Real-Time Transport Protocol
>     [Stream setup by SDP (frame 2754)]
>         [Setup frame: 2754]
>         [Setup Method: SDP]
>     10.. .... = Version: RFC 1889 Version (2)
>     ..0. .... = Padding: False
>     ...0 .... = Extension: False
>     .... 0000 = Contributing source identifiers count: 0
>     1... .... = Marker: True
>     Payload type: ITU-T G.711 PCMU (0)
>     Sequence number: 16399
>     [Extended sequence number: 81935]
>     Timestamp: 480
>     Synchronization Source identifier: 0x07d5dc9c (131456156)
>     Payload: 4f3e352d2b2f42f9dbd2c0b6adaaaec076595241372e2b2e...
> 
> No.     Time            Source                src port Destination           dst port Protocol Info                                                            New Column
>    3567 13:39:29.510447 10.1.1.226            22776    10.1.1.1              18384    RTP      PT=ITU-T G.711 PCMU, SSRC=0x7D5DC9C, Seq=16400, Time=640        214
> 
> Frame 3567: 214 bytes on wire (1712 bits), 214 bytes captured (1712 bits)
>     WTAP_ENCAP: 1
>     Arrival Time: Sep 24, 2013 13:39:29.510447000 CDT
>     [Time shift for this packet: 0.000000000 seconds]
>     Epoch Time: 1380047969.510447000 seconds
>     [Time delta from previous captured frame: 0.002292000 seconds]
>     [Time delta from previous displayed frame: 0.019939000 seconds]
>     [Time since reference or first frame: 30.565953000 seconds]
>     Frame Number: 3567
>     Frame Length: 214 bytes (1712 bits)
>     Capture Length: 214 bytes (1712 bits)
>     [Frame is marked: False]
>     [Frame is ignored: False]
>     [Protocols in frame: eth:ip:udp:rtp]
>     [Coloring Rule Name: UDP]
>     [Coloring Rule String: udp]
> Ethernet II, Src: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a), Dst: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>     Destination: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         Address: Cisco_e8:a0:11 (00:09:e8:e8:a0:11)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Source: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         Address: Hewlett-_b1:3c:0a (00:13:21:b1:3c:0a)
>         .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
>         .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
>     Type: IP (0x0800)
> Internet Protocol Version 4, Src: 10.1.1.226 (10.1.1.226), Dst: 10.1.1.1 (10.1.1.1)
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
>     Total Length: 200
>     Identification: 0x0000 (0)
>     Flags: 0x02 (Don't Fragment)
>         0... .... = Reserved bit: Not set
>         .1.. .... = Don't fragment: Set
>         ..0. .... = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 64
>     Protocol: UDP (17)
>     Header checksum: 0x2341 [correct]
>         [Good: True]
>         [Bad: False]
>     Source: 10.1.1.226 (10.1.1.226)
>     Destination: 10.1.1.1 (10.1.1.1)
> User Datagram Protocol, Src Port: 22776 (22776), Dst Port: 18384 (18384)
>     Source port: 22776 (22776)
>     Destination port: 18384 (18384)
>     Length: 180
>     Checksum: 0x17aa [validation disabled]
>         [Good Checksum: False]
>         [Bad Checksum: False]
> Real-Time Transport Protocol
>     [Stream setup by SDP (frame 2754)]
>         [Setup frame: 2754]
>         [Setup Method: SDP]
>     10.. .... = Version: RFC 1889 Version (2)
>     ..0. .... = Padding: False
>     ...0 .... = Extension: False
>     .... 0000 = Contributing source identifiers count: 0
>     0... .... = Marker: False
>     Payload type: ITU-T G.711 PCMU (0)
>     Sequence number: 16400
>     [Extended sequence number: 81936]
>     Timestamp: 640
>     Synchronization Source identifier: 0x07d5dc9c (131456156)
>     Payload: b6d65c58493b312c2c354fe2daccbcb2abaab3cd5f584c3d...
> 
> 
> 
> 
> 
> From: Michael Jerris <mike at jerris.com>
> To: FreeSWITCH Users Help <freeswitch-users at lists.freeswitch.org> 
> Sent: Wednesday, September 25, 2013 4:45 PM
> Subject: Re: [Freeswitch-users] RTP Wrong Timestamps and audio hiccups in	conferencing output
> 
> Try looking at the time into the call to find the right packets.  Without seeing what exactly is wrong, we are not going to be able to guess what might be going on.
> 
> On Sep 24, 2013, at 1:29 PM, D D <tru083 at yahoo.com> wrote:
> 
>> They are flagged as wrong by Wireshark, in the VoIP RTP Player.
>> 
>> Unfortunately, Wireshark does not allow me to get from the 'W' in player back to the packets
>> it thinks are wrong in the detailed view.
>> 
>> 
>> From: Michael Jerris <mike at jerris.com>
>> To: FreeSWITCH Users Help <freeswitch-users at lists.freeswitch.org> 
>> Sent: Tuesday, September 24, 2013 2:49 PM
>> Subject: Re: [Freeswitch-users] RTP Wrong Timestamps and audio hiccups in	conferencing output
>> 
>> in what way is the timestamp "wrong"?
>> 
>> On Sep 24, 2013, at 3:30 PM, D D <tru083 at yahoo.com> wrote:
>> 
>>> Hi,
>>> 
>>> I am seeing periodic RTP Wrong Timestamps and audio hiccups when using conferencing.
>>> 
>>> I am calling in from two phones on the local LAN, and playing a 440-Hz tone into the conference 
>>> on one of the phones.
>>> 
>>> On the receiving phone, I hear an audio hiccup (and the server-side Wireshark trace shows a 
>>> Wrong Timestamp) about once every 750 ms.  It is very regular on the output from the
>>> conference.  
>>> 
>>> The server-side Wireshark of the input RTP stream looks fine -- there are no anomalies.
>>> 
>>> I am seeing this problem on version 1.2.10 and 1.5.5b.
>>> 
>>> Is this something I need to report as a bug?
>>> 
>>> Thanks,
>>> David
>> 
> 
> 
> _________________________________________________________________________
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> 
> 
> 
> 
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> 
> 
> _________________________________________________________________________
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> consulting at freeswitch.org
> http://www.freeswitchsolutions.com
> 
> 
> 
> 
> Official FreeSWITCH Sites
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> 
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