Consider the following logs from PIX
<166>May 23 2006 21:11:17: %PIX-6-302015: Built inbound UDP connection 12591 for outside:xxxx/1025 (xxxx/53) to inside:xxxx/53 (xxxx/53) (john)
<166>May 23 2006 21:11:17: %PIX-6-302016: Teardown UDP connection 12591 for outside:xxxx/1025 to inside:xxxx/53 duration 0:00:01 bytes 612 (john)
Above logs are part of some udp traffic. For some logs I am getting username here and for others I am not. John is the user who is connecting my network through VPN. Now my question is in what conditions username will appear? Will I always get the username If the traffic is going thrugh VPN?