asterisk3# ngrep -Tn 60 -Wbyline port 5060 | ./sip-dump.pl
 0.000000| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 1 INVITE.        > 
         | CMD: INVITE 71         > 
         |
 0.002808| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 1 INVITE.
         |                        < RES: 407 Proxy Authentication Required
         |
 0.052498| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 1 ACK.           > 
         | CMD: ACK 71            > 
         |
 0.094293| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 2 INVITE.        > 
         | CMD: INVITE 71         > 
         |
 0.096024| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 100 Trying
         |
 0.106540|                          10.252.15.24:5060      > 10.252.11.130:5060
         |                          CSeq: 102 INVITE.      > 
         |                          CMD: INVITE 9096       > 
         |
 0.107915|                          10.252.15.24:5060      < 10.252.11.130:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 100 Trying
         |
 0.129129|                          10.252.15.24:5060      < 10.252.11.130:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 180 Ringing
         |
 0.129465| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 180 Ringing
         |
 3.062715|                          10.252.15.24:5060      < 10.252.11.130:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 200 OK
         |
 3.062732|                          10.252.15.24:5060      > 10.252.11.130:5060
         |                          CSeq: 102 ACK.         > 
         |                          CMD: ACK 9096          > 
         |
 3.063884| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 200 OK
         |
 3.123839| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 2 ACK.           > 
         | CMD: ACK 71            > 
         |
 5.224939|                          10.252.15.24:5060      < 10.252.11.130:5060
         |                                                 < CSeq: 101 BYE.
         |                                                 < CMD: BYE edwin
         |
 5.224979|                          10.252.15.24:5060      > 10.252.11.130:5060
         |                          CSeq: 101 BYE.         > 
         |                          RES: 200 OK            > 
         |
 5.224990| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 102 BYE.
         |                        < CMD: BYE edwin
         |
 6.234925| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 102 BYE.
         |                        < CMD: BYE edwin
         |