On Nov 24, 2009, at 1:13 PM, Templin, Fred L wrote: > In other words, > in my understanding the lease lifetime is primarily about > how often one must refresh their IPv4 address delegation > lifetimes - so, shouldn't that be decoupled from how > often one must refresh their DNS FQDN resolutions?
In the abstract, sure, they should be decoupled. However, that is not the only value that needs to be considered, and I think if you consider all the values, this one doesn't dominate. Bear in mind that DNS TTLs don't specify a sharp edge when the data will be refreshed, so you don't get much benefit from relying on the DNS TTL rather than the lease time. If you want to have a sharp edge, you need a new protocol that leases ISATAP Potential Router List lifetimes. So given that you don't actually get that sharp edge from the DNS TTL, I just don't think it adds much value to prefer the DNS TTL over the lease time as a lifetime for the Potential Router List. On a practical level, the network administrator is just going to have to be aware that there is going to be a period after changing the ISATAP router DNS entries when some clients will have the old addresses, and some clients will have the new addresses, and the network infrastructure will have to be configured to work correctly during that changeover period. _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
