kamailio/Cisco-SIPGateway/IOS-12.x ACK not matched to transa

2017/08/25 20:45:39.347494 20.20.20.20:57950 -> 30.30.30.30:5060
INVITE sip:myuser@30.30.30.30:5060 SIP/2.0
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>
Date: Fri, 25 Aug 2017 17:45:40 GMT
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
Supported: timer,100rel
Min-SE:  1800
Cisco-Guid: 191712370-2297696743-2966937583-2739545882
User-Agent: Cisco-SIPGateway/IOS-12.x
Allow: INVITE, OPTIONS, BYE, CANCEL, ACK, PRACK, COMET, REFER, SUBSCRIBE, NOTIFY, INFO
CSeq: 101 INVITE
Max-Forwards: 10
Remote-Party-ID: <sip:foreignuser@20.20.20.20>;party=calling;screen=no;privacy=off
Timestamp: 1503683140
Contact: <sip:foreignuser@20.20.20.20:5060>
Expires: 180
Allow-Events: telephone-event
Content-Type: application/sdp
Content-Length: 455

v=0
o=CiscoSystemsSIP-GW-UserAgent 6939 6643 IN IP4 20.20.20.20
s=SIP Call
c=IN IP4 20.20.20.20
t=0 0
m=audio 17810 RTP/AVP 8 100 101
c=IN IP4 20.20.20.20
a=rtpmap:8 PCMA/8000
a=rtpmap:100 X-NSE/8000
a=fmtp:100 192-194,200-202
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=ptime:20
a=X-sqn:0
a=X-cap: 1 audio RTP/AVP 100
a=X-cpar: a=rtpmap:100 X-NSE/8000
a=X-cpar: a=fmtp:100 192-194,200-202
a=X-cap: 2 image udptl t38
r: m

2017/08/25 20:45:39.349543 30.30.30.30:5060 -> 20.20.20.20:5060
SIP/2.0 100 trying -- your call is important to us
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
CSeq: 101 INVITE
Server: modCOM v2 SIP Server
Content-Length: 0

-d37

2017/08/25 20:45:40.760781 30.30.30.30:5060 -> 20.20.20.20:5060
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP  20.20.20.20:5060
Record-Route: <sip:30.30.30.30;line=sr-eNC05-sTUXMcQzMcUr4oU7USQ74NUrHzU-Fug-HEe-HxqY1fi7pFVPd2IBUHQ-Is5NIKh2FRUGVo52Bz>
Record-Route: <sip:30.30.30.30;r2=on;lr;ftag=85BECEC-64D;did=a1d.852>
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>;tag=as01313493
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
CSeq: 101 INVITE
Server: modCOM v2 SIP Server
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Session-Expires: 1800;refresher=uas
Contact: <sip:30.30.30.30;line=sr-eNC05-WcQ7WcQ7ezU2A4U7ezy-sTy-srUlMc5-B0Q-4*>
Content-Length: 0

2017/08/25 20:45:42.593465 20.20.20.20:57950 -> 30.30.30.30:5060
CANCEL sip:myuser@30.30.30.30:5060 SIP/2.0
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>
Date: Fri, 25 Aug 2017 17:45:40 GMT
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
CSeq: 101 CANCEL
Max-Forwards: 10
Timestamp: 1503683143
Content-Length: 0

18

2017/08/25 20:45:42.593956 30.30.30.30:5060 -> 20.20.20.20:5060
SIP/2.0 200 canceling
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>;tag=9baa02264c7a600e770692ebb978c317-dede
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
CSeq: 101 CANCEL
Server: modCOM v2 SIP Server
Content-Length: 0

2017/08/25 20:45:42.595218 30.30.30.30:5060 -> 20.20.20.20:5060
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>;tag=as01313493
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
CSeq: 101 INVITE
Server: modCOM v2 SIP Server
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Content-Length: 0

^C


2017/08/25 20:45:42.606466 20.20.20.20:57950 -> 30.30.30.30:5060
ACK sip:myuser@30.30.30.30:5060 SIP/2.0
Via: SIP/2.0/UDP  20.20.20.20:5060
From: <sip:foreignuser@20.20.20.20>;tag=85BECEC-64D
To: <sip:myuser@30.30.30.30>;tag=as01313493
Date: Fri, 25 Aug 2017 17:45:40 GMT
Call-ID: B6DE89A-88F411E7-B0DADFEF-A34A271A@20.20.20.20
Max-Forwards: 10
Content-Length: 0
CSeq: 101 ACK

`^D