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I have a configuration issue in a call scenario where a user has Forward Unconditional to an external number.
The ITSP supports CLIP no screening when the "P-Asserted-Identity" header is configured for inbound external calls, this way the CLIP of the original caller is shown on the screen of the receiver.
The issue is that the receiver sees an extra 0 between the landcode and the CLIP of the original caller.
I can't find a way to configure the SIP trunk to omit the extra 0 from the PAI header.
Any hints?

(External party) A calls B.
B has forward unconditional to (External party) C.
C sees the CLIP of A.

Incoming INVITE Packet.

CODE --> SysMon-Trace

SIP Rx: UDP ->
INVITE sip:10101010@;user=phone SIP/2.0
Accept: application/sdp,application/dtmf-relay
Allow-Events: hold,talk
Call-ID: OA1BAEF000030303030561B3A85
Contact: <sip:030303030@;user=phone>
Content-Type: application/sdp
CSeq: 79793 INVITE
From: <sip:030303030@;user=phone>;tag=21E0
Max-Forwards: 70
P-Preferred-Identity: <sip:>
Privacy: none
Supported: replaces
To: <sip:10101010@;user=phone>
Via: SIP/2.0/UDP;branch=z9hG4bK-70A8-140C5
Content-Length: 210

o=User1 3715581931 3715581931 IN IP4
s=Session SDP
c=IN IP4
t=0 0
m=audio 16486 RTP/AVP 8 101
a=rtpmap:8 PCMA/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15

Outgoing INVITE packet

CODE --> SysMon-Trace

SIP Tx: UDP ->
INVITE sip:0464646464@;user=phone SIP/2.0
Via: SIP/2.0/UDP;rport;branch=z9hG4bK51280cb78413e8605ba8dced95d22075
From: "Fwd UC" <sip:10101010@;user=phone>;tag=fe90d7802dad0a8b
To: <sip:0464646464@;user=phone>
Call-ID: 145aaa15c43bcae7d80b35bce6d31f8b
CSeq: 44636634 INVITE
Contact: "Fwd UC" <sip:299@;transport=udp>
Max-Forwards: 70
Supported: timer,100rel
User-Agent: IP Office build 10
Diversion: "Fwd UC" <sip:299@>;reason=direct;screen=no;privacy=off;counter=1
P-Asserted-Identity: <sip:030303030@>
Content-Type: application/sdp
Content-Length: 198

o=UserA 1394312431 2670905046 IN IP4
s=Session SDP
c=IN IP4
t=0 0
m=audio 54000 RTP/AVP 8 101
a=rtpmap:8 PCMA/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15 

RE: P-Asserted-Identity

Do you have the prefixes set on the SIP Line?

"Trying is the first step to failure..." - Homer

RE: P-Asserted-Identity

Yes I have got:
National Prefix 0
International Prefix 00
Country Code 32

Without these prefixes it's not possible to make calls from the call log.

RE: P-Asserted-Identity

Since you completely messed up the numbers it's hard to tell what the number format is, could have kept the first 4-5 digits intact.

Does your national numbers start with a 0?

"Trying is the first step to failure..." - Homer

RE: P-Asserted-Identity

Indeed, the trace is worthless as you have totally changed/obscured the only relevant information in there smile

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