sterisk3# 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 81         > 
         |
 0.003084| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 1 INVITE.
         |                        < RES: 407 Proxy Authentication Required
         |
 0.053845| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 1 ACK.           > 
         | CMD: ACK 81            > 
         |
 0.095272| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 2 INVITE.        > 
         | CMD: INVITE 81         > 
         |
 0.095321| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 100 Trying
         |
 0.250502|                          10.252.15.24:5060      > 10.252.15.25:5060
         |                          CSeq: 102 INVITE.      > 
         |                          CMD: INVITE 81         > 
         |
 0.254653|                          10.252.15.24:5060      < 10.252.15.25:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 100 Trying
         |
 0.295177|                                                   10.252.15.25:5060      > 10.252.11.130:5060
         |                                                   CSeq: 102 INVITE.      > 
         |                                                   CMD: INVITE 9096       > 
         |
 0.296233|                                                   10.252.15.25:5060      < 10.252.11.130:5060
         |                                                                          < CSeq: 102 INVITE.
         |                                                                          < RES: 100 Trying
         |
 0.322457|                                                   10.252.15.25:5060      < 10.252.11.130:5060
         |                                                                          < CSeq: 102 INVITE.
         |                                                                          < RES: 180 Ringing
         |
 0.324625|                          10.252.15.24:5060      < 10.252.15.25:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 180 Ringing
         |
 0.324963| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 180 Ringing
         |
 3.676491|                                                   10.252.15.25:5060      < 10.252.11.130:5060
         |                                                                          < CSeq: 102 INVITE.
         |                                                                          < RES: 200 OK
         |
 3.676557|                                                   10.252.15.25:5060      > 10.252.11.130:5060
         |                                                   CSeq: 102 ACK.         > 
         |                                                   CMD: ACK 9096          > 
         |
 3.676582|                          10.252.15.24:5060      < 10.252.15.25:5060
         |                                                 < CSeq: 102 INVITE.
         |                                                 < RES: 200 OK
         |
 3.677055|                          10.252.15.24:5060      > 10.252.15.25:5060
         |                          CSeq: 102 ACK.         > 
         |                          CMD: ACK 81            > 
         |
 3.677506| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 2 INVITE.
         |                        < RES: 200 OK
         |
 3.778799| 10.251.1.21:5060       > 10.252.15.24:5060
         | CSeq: 2 ACK.           > 
         | CMD: ACK 81            > 
         |
 9.976685|                                                   10.252.15.25:5060      < 10.252.11.130:5060
         |                                                                          < CSeq: 101 BYE.
         |                                                                          < CMD: BYE edwin
         |
 9.976708|                                                   10.252.15.25:5060      > 10.252.11.130:5060
         |                                                   CSeq: 101 BYE.         > 
         |                                                   RES: 200 OK            > 
         |
 9.977658|                          10.252.15.24:5060      < 10.252.15.25:5060
         |                                                 < CSeq: 102 BYE.
         |                                                 < CMD: BYE edwin
         |
 9.977678|                          10.252.15.24:5060      > 10.252.15.25:5060
         |                          CSeq: 102 BYE.         > 
         |                          RES: 200 OK            > 
         |
 9.978234| 10.251.1.21:5060       < 10.252.15.24:5060
         |                        < CSeq: 102 BYE.
         |                        < CMD: BYE edwin
         |