It's how you handle the exceptions. Home users have port 25 off by default but can still get it turned on. Most home users don't need a public IP address as they are not running stuff that requires it however some do so planning to handle the exceptions as efficiently as possible is a good thing to do.
I disagree. I look forward to a day when all home users by default have a public IPv6 address for each of their machines and hopefully enough to support multiple subnets within the home. Until then, IPv4 service without at least one public IP is degraded at best compared to what most people consider normal residential internet access today (which, frankly, is degraded at best compared to what I consider normal internet access).
I've got two applications that won't work behind a LSN. A sip phone and a 6in4 tunnel however I'm not typical.
You're not that atypical either, at least compared to US users. The following very common applications are known to have problems with LSN: Playstation Network X-Box Live AIM/iChat/FaceTime SIP/Vonage/other VoIP services The HTTPs Server on TiVO boxes Peer to Peer (torrent, etc.) Other less common applications also have problems: HTTP servers SMTP servers Back to my Mac VNC Tunnels
Looking at 6to4 and auto tunnels they really are a small percentage of customers that could be auto detected by the ISP and be put into the exception pool prior to enabling LSN. Most CPE routers today don't enable 6to4 (they either don't support IPv6 let alone 6to4 or its not turned on by default). As for directly connected machines many of then still require 6to4 to be turned on by hand (XP, Mac OS).
While this is true, I'm not sure it's all that relevant. Most ISPs I have talked to in the US are dreading the deployment of LSN and not planning to deploy it by default except to the extent absolutely necessary to meet customer demand.
What's easier for the ISP, detecting the customers that use protocol 41 today and automatically adding them to a exception pool or fielding the support calls?
Moving them to IPv6 and hoping that enough of the content providers move forward fast enough to minimize the extent of the LSN deployment required. Owen
Mark
Without any commitments to cite, plan for the worst and hope for the best.
Cb
If I were doing it I would also have checkboxes for some of the more common reasons and include IPv6 connectivity as one then have a 6 month grace period once the ISP offers IPv6 connectivity before removing that as a valid reason for needing a address that is not behind the LSN.
LSN is beeing actively implemented in the core network of several ISPs, and most didn't yet consider it as optional. Nor are ready for v6 connectivity to residential customers, though.
For users behind a forced NAT (no way to disable it on the CPE) or LSN, the only way out is still tunneling. Talking about bandwidth and infrastructure waste... -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka@isc.org -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka@isc.org