No.     Time        Source                Destination           Protocol Info
    670 17.141060   192.168.1.11          192.168.1.15          SIP      Status: 180 Ringing

Frame 670 (490 bytes on wire, 490 bytes captured)
Linux cooked capture
Internet Protocol, Src: 192.168.1.11 (192.168.1.11), Dst: 192.168.1.15 (192.168.1.15)
User Datagram Protocol, Src Port: sip (5060), Dst Port: sip (5060)
Session Initiation Protocol
    Status-Line: SIP/2.0 180 Ringing
    Message Header
        Via: SIP/2.0/UDP 192.168.1.15;branch=z9hG4bK1073544afa2a6ecd
        Via: SIP/2.0/UDP 192.168.1.10;branch=z9hG4bK1073544afa2a6ecd
        Record-Route: <sip:192.168.1.15;lr=on;ftag=b03fbb977e692e28>
        From: <sip:+41215501111@192.168.1.15>;tag=b03fbb977e692e28
        To: <sip:+41215509999@192.168.1.15>;tag=2d39d82d4efb221d
        Call-ID: 3f6b72ef41379493@192.168.1.10
        CSeq: 43883 INVITE
        User-Agent: Grandstream BT110 1.0.8.33
        Content-Length: 0