Re: [homenet] Please review the No IPv4 draft
In your letter dated Thu, 17 Apr 2014 22:16:19 -0430 you wrote: I like the idea of having the No-IPv4 option for DHCPv6. I don't like the idea of having this option in a v4 world; mainly because in mix networks where you might have some folks which only speak IPv4, imagine a case where this option is sent by a DHCPv4 to a client who do not understand v6. Of course, probably the client won't understand the option and won't turn off IPv4. There is also the chance that this is a modern OS but for some reason IPv6 was disable in the host, yes, it will understand the option No-VP6 (sent by a dhcp4). As far as I understand, this draft addresses the situation where the network doesn't offer IPv4 in the first place. So any IPv4-only host would have no internet connectivity anyhow, whether it processes the option or not. ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
Re: [homenet] Please review the No IPv4 draft
Le 2014-04-17 17:14, Mark Andrews a écrit : 0 full IPv4 connectivity 1 all IPv4 off on the interface 2 local (link/site not global) connectivity only on the interface 3 no IPv4 on the machine. Uh, no. The levels are in strictly increasing order. 2 includes everything in 1, plus some more: 2 - No IPv4 upstream, local IPv4 restricted: Same semantics as value 1, with the following additions: 2 deals with propagation to downstream interfaces. It has nothing to do with link or site local stuff. Part of the problem here is that upstream is the only interface for singlely attached devices other than loopback. There is no only local connectivity is available step for such nodes. Correct. For such nodes, 1 == 2. Is that a problem? It's still a stairway going up, with steps 1 and 2 being at the same height for a subset of nodes. Simon 0 - IPv4 fully enabled: This is equivalent to the absence of the No- IPv4 option. It is included here so that a DHCPv6 server can explicitly re-enable IPv4 access by including it in a Reply message following a Reconfigure, or similarly by a router in a spontaneous Router Advertisement. 1 - No IPv4 upstream: Any kind of IPv4 connectivity is unavailable on the link on which the option is received. Therefore, any attempts to provision IPv4 by the host or to use IPv4 in any fashion, on that link, will be useless. IPv4 MAY be dropped, blocked, or otherwise ignored on that link. Mark -- DTN made easy, lean, and smart -- http://postellation.viagenie.ca NAT64/DNS64 open-source-- http://ecdysis.viagenie.ca STUN/TURN server -- http://numb.viagenie.ca ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
Re: [homenet] Please review the No IPv4 draft
Le 2014-04-17 23:49, Lorenzo Colitti a écrit : On Thu, Apr 17, 2014 at 11:24 PM, Simon Perreault simon.perrea...@viagenie.ca mailto:simon.perrea...@viagenie.ca wrote: Le 2014-04-16 12:25, Simon Kelley a écrit : Android uses dhcpcd as its DHCP client. Thought about this some more... Doesn't dhcpcd implement everything in a single daemon? i.e., DHCPv4, DHCPv4, IPv4LL, IPv6 RS? If so, then it would be easy for one protocol to affect another, wouldn't it? In practice, you can't use dhcpcd for autoconf because it doesn't support privacy addresses or removing the default route when the RA lifetime expires. (Or at least, the 6.3.2 version I downloaded today and ran on Debian stable didn't seem to support this). So you still need to run kernel autoconf, at which point you might as well disable dhdpcd's RS processing since you probably don't want both the kernel and dhcpcd to be running autoconf. Got it. So, summarizing, for Android, DHCPv4 and DHCPv6 options would likely not be problematic, but an RA option likely would. Thanks, Simon -- DTN made easy, lean, and smart -- http://postellation.viagenie.ca NAT64/DNS64 open-source-- http://ecdysis.viagenie.ca STUN/TURN server -- http://numb.viagenie.ca ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
Re: [homenet] Please review the No IPv4 draft
Hi Philip, El 4/18/2014 3:28 AM, Philip Homburg escribió: In your letter dated Thu, 17 Apr 2014 22:16:19 -0430 you wrote: I like the idea of having the No-IPv4 option for DHCPv6. I don't like the idea of having this option in a v4 world; mainly because in mix networks where you might have some folks which only speak IPv4, imagine a case where this option is sent by a DHCPv4 to a client who do not understand v6. Of course, probably the client won't understand the option and won't turn off IPv4. There is also the chance that this is a modern OS but for some reason IPv6 was disable in the host, yes, it will understand the option No-VP6 (sent by a dhcp4). As far as I understand, this draft addresses the situation where the network doesn't offer IPv4 in the first place. You are absolutely right, thanks. But anyway the scenario I mentioned above can also exists (and for good or bad eventually will happen).. I just wanted to express my position about the option NO-IPv4 in DHCPv4 So any IPv4-only host would have no internet connectivity anyhow, whether it processes the option or not. ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
Re: [homenet] Please review the No IPv4 draft
On Apr 18, 2014, at 7:51 AM, Simon Perreault simon.perrea...@viagenie.ca wrote: Got it. So, summarizing, for Android, DHCPv4 and DHCPv6 options would likely not be problematic, but an RA option likely would. This is weird, though. How does a DHCPv6 client know to attempt configuration, if it doesn't see RAs? I just hacked around this on my router at home in order to get Comcast IPv6 working, but that seems broken. ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
Re: [homenet] Please review the No IPv4 draft
Le 2014-04-18 11:56, Ted Lemon a écrit : On Apr 18, 2014, at 7:51 AM, Simon Perreault simon.perrea...@viagenie.ca wrote: Got it. So, summarizing, for Android, DHCPv4 and DHCPv6 options would likely not be problematic, but an RA option likely would. This is weird, though. How does a DHCPv6 client know to attempt configuration, if it doesn't see RAs? I just hacked around this on my router at home in order to get Comcast IPv6 working, but that seems broken. I don't know how Android does it, but any DHCPv6 client is free to unilaterally attempt configuration. It doesn't need to wait for an RA to tell it to do so. RAs are just a hint. Simon -- DTN made easy, lean, and smart -- http://postellation.viagenie.ca NAT64/DNS64 open-source-- http://ecdysis.viagenie.ca STUN/TURN server -- http://numb.viagenie.ca ___ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
