Core Issue
The VPN 3002 Hardware Client may be configured to work in Port Address Translation (PAT) mode.
Resolution
VPN 3002 is capable of operating in two modes: Client mode and NEM (Network Extension Mode). In Client mode, all the hosts earlier than the 3002 are in PAT mode to the outside IP address of the 3002. However, PAT breaks H.323. H.323 does not work with PAT.
When the VPN 3002 works in NEM, the remote networks are capable of seeing each other using their real IP addresses, not a NAT or PAT IP address. If the VPN 3002 works in NEM, then H.323 works.
IP phones earlier than a 3002 work only in NEM.
To configure the VPN to work in NEM, perform these steps:
- Select Configuration > Quick > PAT.
- Choose No, use Network Extension mode from the PAT window to configure NEM.
For more information on configuring Cisco VPN 3002 Hardware Client, refer to Configuring Cisco VPN 3002 Hardware Client to Cisco IOS Router with EzVPN in Network Extension Mode.
For related information on one-way voice issues, refer to Troubleshooting One Way Voice Issues.
Problem Type
Call connection (Connection quality: One-way audio, no busy tone, dropped calls, etc.)
IP phones and other clients (Client registration, faulty IP phone, etc.)
Call Connection
One-way audio
IP Phones and Clients
IP phone faulty operation
Common Software and Product Issues
Compatibility
Failure Type
Cannot connect to server, disconnect, register, synchronize, communicate, etc.
Cannot perform routine, step, function, etc.
Frequency and Scope of Symptom
Only occurs in one direction
When Problem Occurs
During conversation
End Where Problem is Heard or Device Type Involved
IP phone
Call Topology and Direction
IP network > IP network
IP network > PSTN/PBX/gateway > IP network
Security Features
Virtual Private Network (VPN)
