INVITE sip:user@domain SIP/2.0
Via: SIP/2.0/UDP host.test.com
From: Caller <sip:caller@domain.com>
To: Callee <sip:callee@domain>
Call-ID: 86888aab87@10.0.1.1
CSeq: 0 INVITE
Content-Length: 0


INVITE sip:user2@domain SIP/2.0
Via: SIP/2.0/UDP host.test.com
From: Caller <sip:caller@domain.com>
To: Callee 2 <sip:callee2@domain>
Call-ID: 088bbcfb87@10.0.1.1
CSeq: 1 INVITE
Content-Length: 10

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