System Details:
Build 5.1.4510
Windows Server 2003
One network-facing IP (192.168.0.12), one Internet-facing IP (64.50.120.xx), both statically assigned
IPSEC is enabled on the public IP so that only specified IPs and protocols can get through.
Problem:
I have one external extension that registers through that Internet-facing IP. Her phone, too, is behind a NAT device. STUN is enabled on the phone. After her extension registers, I can pick up a local extension (225), dial her extension (408), and the call is completed without a problem. Two-way audio is clear with no latency.
However, if SHE picks up the phone and tries to dial an extension, the recipient extension will ring but no audio is transmitted in either direction after the phone is picked up.
I know if I can call her (local to remote), it's probably not a firewall issue on her end. Likewise, as I'm running IPSEC and no firewall on my end and her phone can register fine, it's not a firewall issue on my end.
How do I resolve this?
Logs:
Ethereal capture of what I suspect the problem is:
This is the Notify packet being sent from her phone to my phone
No. Time Source Destination Protocol Info
40 4.736673 76.212.103.xx 64.50.120.xx SIP Request: NOTIFY sip:64.50.120.xx
Frame 40 (371 bytes on wire, 371 bytes captured)
Arrival Time: Jun 18, 2008 13:45:43.422414000
[Time delta from previous captured frame: 0.111320000 seconds]
[Time delta from previous displayed frame: 0.111320000 seconds]
[Time since reference or first frame: 4.736673000 seconds]
Frame Number: 40
Frame Length: 371 bytes
Capture Length: 371 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:sip]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Cisco_3d:6b:da (00:0c:86:3d:6b:da), Dst: Dell_f6:db:64 (00:18:8b:f6:db:64)
Destination: Dell_f6:db:64 (00:18:8b:f6:db:64)
Source: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Type: IP (0x0800)
Internet Protocol, Src: 76.212.103.71 (76.212.103.71), Dst: 64.50.120.38 (64.50.120.38)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
Total Length: 357
Identification: 0x1528 (5416)
Flags: 0x00
Fragment offset: 0
Time to live: 235
Protocol: UDP (0x11)
Header checksum: 0x4cec [correct]
Source: 76.212.103.xx (76.212.103.xx)
Destination: 64.50.120.xx (64.50.120.xx)
User Datagram Protocol, Src Port: sip (5060), Dst Port: sip (5060)
Source port: sip (5060)
Destination port: sip (5060)
Length: 337
Checksum: 0x331f [correct]
[Good Checksum: True]
[Bad Checksum: False]
Session Initiation Protocol
Request-Line: NOTIFY sip:64.50.120.xx SIP/2.0
Method: NOTIFY
[Resent Packet: False]
Message Header
Via: SIP/2.0/UDP 192.168.1.100:5060;branch=z9hG4bK-8064dec0
Transport: UDP
Sent-by Address: 192.168.1.100
Sent-by port: 5060
Branch: z9hG4bK-8064dec0
From: "408" <sip:[email protected]>;tag=a5ece676b0eeb13o0
SIP Display info: "408"
SIP from address: sip:[email protected]
SIP tag: a5ece676b0eeb13o0
To: <sip:64.50.120.xx>
SIP to address: sip:64.50.120.xx
Call-ID: [email protected]
CSeq: 4055 NOTIFY
Sequence Number: 4055
Method: NOTIFY
Max-Forwards: 70
Event: keep-alive
User-Agent: Linksys/SPA922-5.2.5
Content-Length: 0
This is the Method Not Supported Return Packet. Occurs whenever I pick up the phone when she calls
No. Time Source Destination Protocol Info
42 4.843422 64.50.120.xx 76.212.103.xx SIP Status: 405 Method Not Allowed
Frame 42 (384 bytes on wire, 384 bytes captured)
Arrival Time: Jun 18, 2008 13:45:43.529163000
[Time delta from previous captured frame: 0.000343000 seconds]
[Time delta from previous displayed frame: 0.000343000 seconds]
[Time since reference or first frame: 4.843422000 seconds]
Frame Number: 42
Frame Length: 384 bytes
Capture Length: 384 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:sip]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Dell_f6:db:64 (00:18:8b:f6:db:64), Dst: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Destination: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Source: Dell_f6:db:64 (00:18:8b:f6:db:64)
Type: IP (0x0800)
Internet Protocol, Src: 64.50.120.xx (64.50.120.xx), Dst: 76.212.103.xx (76.212.103.xx)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
Total Length: 370
Identification: 0x4c64 (19556)
Flags: 0x00
Fragment offset: 0
Time to live: 128
Protocol: UDP (0x11)
Header checksum: 0x80a3 [correct]
Source: 64.50.120.x (64.50.120.xx)
Destination: 76.212.103.xx (76.212.103.xx)
User Datagram Protocol, Src Port: sip (5060), Dst Port: sip (5060)
Source port: sip (5060)
Destination port: sip (5060)
Length: 350
Checksum: 0x7e1a [correct]
[Good Checksum: True]
[Bad Checksum: False]
Session Initiation Protocol
Status-Line: SIP/2.0 405 Method Not Allowed
Status-Code: 405
[Resent Packet: False]
Message Header
Via: SIP/2.0/UDP 192.168.1.100:5060;branch=z9hG4bK-8064dec0;received=76.212.103.xx;rport=5060
Transport: UDP
Sent-by Address: 192.168.1.100
Sent-by port: 5060
Branch: z9hG4bK-8064dec0
Received: 76.212.103.xx
RPort: 5060
To: <sip:64.50.120.xx>;tag=8e23414b
SIP to address: sip:64.50.120.xx
SIP tag: 8e23414b
From: "408"<sip:[email protected]>;tag=a5ece676b0eeb13o0
SIP Display info: "408"
SIP from address: sip:[email protected]
SIP tag: a5ece676b0eeb13o0
Call-ID: [email protected]
CSeq: 4055 NOTIFY
Sequence Number: 4055
Method: NOTIFY
User-Agent: 3CXPhoneSystem 5.1.4510.0
Content-Length: 0
Build 5.1.4510
Windows Server 2003
One network-facing IP (192.168.0.12), one Internet-facing IP (64.50.120.xx), both statically assigned
IPSEC is enabled on the public IP so that only specified IPs and protocols can get through.
Problem:
I have one external extension that registers through that Internet-facing IP. Her phone, too, is behind a NAT device. STUN is enabled on the phone. After her extension registers, I can pick up a local extension (225), dial her extension (408), and the call is completed without a problem. Two-way audio is clear with no latency.
However, if SHE picks up the phone and tries to dial an extension, the recipient extension will ring but no audio is transmitted in either direction after the phone is picked up.
I know if I can call her (local to remote), it's probably not a firewall issue on her end. Likewise, as I'm running IPSEC and no firewall on my end and her phone can register fine, it's not a firewall issue on my end.
How do I resolve this?
Logs:
Ethereal capture of what I suspect the problem is:
This is the Notify packet being sent from her phone to my phone
No. Time Source Destination Protocol Info
40 4.736673 76.212.103.xx 64.50.120.xx SIP Request: NOTIFY sip:64.50.120.xx
Frame 40 (371 bytes on wire, 371 bytes captured)
Arrival Time: Jun 18, 2008 13:45:43.422414000
[Time delta from previous captured frame: 0.111320000 seconds]
[Time delta from previous displayed frame: 0.111320000 seconds]
[Time since reference or first frame: 4.736673000 seconds]
Frame Number: 40
Frame Length: 371 bytes
Capture Length: 371 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:sip]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Cisco_3d:6b:da (00:0c:86:3d:6b:da), Dst: Dell_f6:db:64 (00:18:8b:f6:db:64)
Destination: Dell_f6:db:64 (00:18:8b:f6:db:64)
Source: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Type: IP (0x0800)
Internet Protocol, Src: 76.212.103.71 (76.212.103.71), Dst: 64.50.120.38 (64.50.120.38)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
Total Length: 357
Identification: 0x1528 (5416)
Flags: 0x00
Fragment offset: 0
Time to live: 235
Protocol: UDP (0x11)
Header checksum: 0x4cec [correct]
Source: 76.212.103.xx (76.212.103.xx)
Destination: 64.50.120.xx (64.50.120.xx)
User Datagram Protocol, Src Port: sip (5060), Dst Port: sip (5060)
Source port: sip (5060)
Destination port: sip (5060)
Length: 337
Checksum: 0x331f [correct]
[Good Checksum: True]
[Bad Checksum: False]
Session Initiation Protocol
Request-Line: NOTIFY sip:64.50.120.xx SIP/2.0
Method: NOTIFY
[Resent Packet: False]
Message Header
Via: SIP/2.0/UDP 192.168.1.100:5060;branch=z9hG4bK-8064dec0
Transport: UDP
Sent-by Address: 192.168.1.100
Sent-by port: 5060
Branch: z9hG4bK-8064dec0
From: "408" <sip:[email protected]>;tag=a5ece676b0eeb13o0
SIP Display info: "408"
SIP from address: sip:[email protected]
SIP tag: a5ece676b0eeb13o0
To: <sip:64.50.120.xx>
SIP to address: sip:64.50.120.xx
Call-ID: [email protected]
CSeq: 4055 NOTIFY
Sequence Number: 4055
Method: NOTIFY
Max-Forwards: 70
Event: keep-alive
User-Agent: Linksys/SPA922-5.2.5
Content-Length: 0
This is the Method Not Supported Return Packet. Occurs whenever I pick up the phone when she calls
No. Time Source Destination Protocol Info
42 4.843422 64.50.120.xx 76.212.103.xx SIP Status: 405 Method Not Allowed
Frame 42 (384 bytes on wire, 384 bytes captured)
Arrival Time: Jun 18, 2008 13:45:43.529163000
[Time delta from previous captured frame: 0.000343000 seconds]
[Time delta from previous displayed frame: 0.000343000 seconds]
[Time since reference or first frame: 4.843422000 seconds]
Frame Number: 42
Frame Length: 384 bytes
Capture Length: 384 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:sip]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Dell_f6:db:64 (00:18:8b:f6:db:64), Dst: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Destination: Cisco_3d:6b:da (00:0c:86:3d:6b:da)
Source: Dell_f6:db:64 (00:18:8b:f6:db:64)
Type: IP (0x0800)
Internet Protocol, Src: 64.50.120.xx (64.50.120.xx), Dst: 76.212.103.xx (76.212.103.xx)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
Total Length: 370
Identification: 0x4c64 (19556)
Flags: 0x00
Fragment offset: 0
Time to live: 128
Protocol: UDP (0x11)
Header checksum: 0x80a3 [correct]
Source: 64.50.120.x (64.50.120.xx)
Destination: 76.212.103.xx (76.212.103.xx)
User Datagram Protocol, Src Port: sip (5060), Dst Port: sip (5060)
Source port: sip (5060)
Destination port: sip (5060)
Length: 350
Checksum: 0x7e1a [correct]
[Good Checksum: True]
[Bad Checksum: False]
Session Initiation Protocol
Status-Line: SIP/2.0 405 Method Not Allowed
Status-Code: 405
[Resent Packet: False]
Message Header
Via: SIP/2.0/UDP 192.168.1.100:5060;branch=z9hG4bK-8064dec0;received=76.212.103.xx;rport=5060
Transport: UDP
Sent-by Address: 192.168.1.100
Sent-by port: 5060
Branch: z9hG4bK-8064dec0
Received: 76.212.103.xx
RPort: 5060
To: <sip:64.50.120.xx>;tag=8e23414b
SIP to address: sip:64.50.120.xx
SIP tag: 8e23414b
From: "408"<sip:[email protected]>;tag=a5ece676b0eeb13o0
SIP Display info: "408"
SIP from address: sip:[email protected]
SIP tag: a5ece676b0eeb13o0
Call-ID: [email protected]
CSeq: 4055 NOTIFY
Sequence Number: 4055
Method: NOTIFY
User-Agent: 3CXPhoneSystem 5.1.4510.0
Content-Length: 0
