Hello, Selon John Spence <[EMAIL PROTECTED]>:
> Reading RFC 4291, I am not 100% clear on the format for link-local > addresses. In some places the document specifies "fe80::/10", which I > read as "the first ten bits must be 1111 1110 10, the remaining 54 bits > can be anything, up to the /64 bit boundary . Later in the document I > see this: > > > > 2.5.6. Link-Local IPv6 Unicast Addresses > > Link-Local addresses are for use on a single link. Link-Local > addresses have the following format: > > | 10 | > | bits | 54 bits | 64 bits | > +----------+-------------------------+----------------------------+ > |1111111010| 0 | interface ID | > > > > Which I read as "the first 64 bits are always fe80::", but then I would > think we'd write that as "fe80::/64". > > > > So, do those middle 54 bits have to be zero, or can they be anything? > I ping6ed my Linux link-local address with those 54 bits equaling 0: [EMAIL PROTECTED]:~$ ping6 -I eth1 fe80:0:0::2c0:9fff:feef:ffb4 PING fe80:0:0::2c0:9fff:feef:ffb4(fe80::2c0:9fff:feef:ffb4) from fe80::2c0:9fff:feef:ffb4 eth1: 56 data bytes 64 bytes from fe80::2c0:9fff:feef:ffb4: icmp_seq=1 ttl=64 time=0.041 ms 64 bytes from fe80::2c0:9fff:feef:ffb4: icmp_seq=2 ttl=64 time=0.034 ms Then, I tried to ping6 my link-local address by modifying some of your 54 bits: [EMAIL PROTECTED]:~$ ping6 -I eth1 fe80:0:1::2c0:9fff:feef:ffb4 connect: Network is unreachable [EMAIL PROTECTED]:~$ Looks like Linux likes them when they are zero. :-/ I'm not sure what this means. I hope this helps. Regards, pars > > > Thanks for any insight. > > > > > > John Spence, Command Information > > [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > > > > ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program. -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
