ip server sending multiple REGISTER requests with different CALL-ID and that is the reason all running calls will get dropped and may result in intermittent call failure as soon as Re-REGISTER request comes with New CALL-ID. Please refer below logs and advise customer accordingly.
Also if he has set 3600 secs at his end then ideally the next registration request should come only after one hour .
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Sequence No.:78
REGISTER sip:10.162.203.6 SIP/2.0
Via: SIP/2.0/UDP 10.162.203.122:5060;branch=z9hG4bK606dbb1de44224331431
To: <sip:66278800@10.162.203.6>
From: <sip:66278800@10.162.203.6>;tag=as143a7f18
Call-ID:
799201ec43aaba18413a0dcf50ec2820@127.0.0.1CSeq: 103 REGISTER
Event: registration
Expires: 3600
Max-Forwards: 69
Contact: <sip:66278800@10.162.203.122>;useradd=10.0.69.42;userport=5060
P-Access-Network-Info: 3GPP-UTRAN-TDD
Supported: path
User-Agent: Asterisk PBX
Content-Length: 0
Authorization: Digest username="66278800",realm="SIP-66278800",nonce="524988d5c3b32c4b10886200c9f88335",uri="sip:10.0.69.2",response="ed5695da8e6bb4316e7e1f4433120336",algorithm=MD5
Sequence No.:79
SIP/2.0 200 OK
Via: SIP/2.0/UDP 10.162.203.122:5060;branch=z9hG4bK606dbb1de44224331431
To: <sip:66278800@10.162.203.6>
From: <sip:66278800@10.162.203.6>;tag=as143a7f18
Call-ID:
799201ec43aaba18413a0dcf50ec2820@127.0.0.1CSeq: 103 REGISTER
Contact: <sip:66278800@10.162.203.122>;useradd=10.0.69.42;userport=5060;expires=3600
Date: Tue, 28 Nov 2017 11:51:17 GMT
User-Agent: ZTE-SoftSwitch
Content-Length: 0
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Sequence No.:82
REGISTER sip:10.162.203.6 SIP/2.0
Via: SIP/2.0/UDP 10.162.203.122:5060;branch=z9hG4bK3b08813cfe8d0abaa088
To: <sip:66278800@10.162.203.6>
From: <sip:66278800@10.162.203.6>;tag=as431e8352
Call-ID:
192f314a629b70265f08569f304ea48c@127.0.0.1CSeq: 103 REGISTER
Event: registration
Expires: 3600
Max-Forwards: 69
Contact: <sip:66278800@10.162.203.122>;useradd=10.0.69.42;userport=5060
P-Access-Network-Info: 3GPP-UTRAN-TDD
Supported: path
User-Agent: Asterisk PBX
Content-Length: 0
Authorization: Digest username="66278800",realm="SIP-66278800",nonce="29f139355bb797f4f70f76ea254c8c10",uri="sip:10.0.69.2",response="de8b0d171bd416347a6fb8928f04d33c",algorithm=MD5
Sequence No.:83
SIP/2.0 200 OK
Via: SIP/2.0/UDP 10.162.203.122:5060;branch=z9hG4bK3b08813cfe8d0abaa088
To: <sip:66278800@10.162.203.6>
From: <sip:66278800@10.162.203.6>;tag=as431e8352
Call-ID:
192f314a629b70265f08569f304ea48c@127.0.0.1CSeq: 103 REGISTER
Contact: <sip:66278800@10.162.203.122>;useradd=10.0.69.42;userport=5060;expires=3600
Date: Tue, 28 Nov 2017 11:51:17 GMT
User-Agent: ZTE-SoftSwitch
Content-Length: 0
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