> VPNs typically do OK Assuming the network administrator has configured his router for VPN pass through [1]. > SIP does not "work fine" in an IPv4 only envir

> VPNs typically do OK Assuming the network administrator has configured his router for VPN pass through [1]. > SIP does not "work fine" in an IPv4 only environment, as any NAT user will attest to. Seems to work fine for me. The built in SIP client for Android works great in IPv4 both NAT and non-NAT. However, it seems to have some issues with IPv6 (not surprised due to the lack of feedback on the Android bug tracker...). Zoiper on the other hand will work through pretty much anything you throw at it. I'm not saying SIP is perfect - but my experiences with SIP have been generally positive with Asterisk. Now I'm also in control of Asterisk and can tweak the configuration - I'm sure a lot of canned SIP systems are completely broken. [1] http://www.tp-link.us/FAQ-558.html http://www.tp-link.us/FAQ-558.html