Hello Dmitry, My view is that 4rd is most easily understood if and only if it connects to a CE function that is performing NAPT. The CE function may be in what is traditionally considered a host, or in what is clearly a router.
More specifically, a device that is forwarding packets from one interface (virtual or otherwise) to another through a NAPT that has one interface with IPv6 configured (via DHCPv6 or otherwise) as performing 4rd (which enables dual-stack via a port-restricted IPv4 address for the NAPT using IPv6 as the transport) then you a have a 4rd CE. That could be a "host" in that it is a Windows PC with internet connection sharing for IPv4 turned on and hence forwards packets between interfaces with a NAPT due to the IPv4-enabled interface created when 4rd is configured. I would avoid anything that requires the host forwarding table to be altered to accommodate 4rd. Instead, the NAPT function that is already present in a small router or host configured to look like a router is modified to use a set of ports that it is allowed to use when 4rd is enabled. - Mark On Apr 12, 2011, at 2:11 AM, Dmitry Anipko wrote: > Hi, > > Since re-chartering to include 4rd has not been approved yet (as far as I > know), I'm not sure if softwires is the right forum for this question, please > let me know if intarea is a better one for the time being. > > Draft-despres-intarea-4rd-01 allows for configuration of end hosts (since it > defines CE as "a host, a router or both") with shared addresses with > restricted port sets. My understanding is that usage by applications of such > addresses, assigned to interfaces, may have issues - for example, those are > discussed in http://tools.ietf.org/html/draft-dec-stateless-4v6-00 . > > Should the draft include a recommendation to either avoid assigning such > addresses to interfaces, and use it only in the NAT function, even when CE is > a host, or, as draft-dec-stateless-4v6-00 suggests in section 3.1.2, modify > the 4rd DHCP option to provide for CE ability to specify whether it is > capable to function with a shared address? (since 4rd can also distribute not > shared addresses / address ranges) > > Thank you, > Dmitry > > _______________________________________________ > Softwires mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/softwires _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
