[Planetlab-devel] IPv6 support for MyPLC

[Marc E. Fiuczynski]

Hello,

Here is the summary of what we could do for the following:

> 1) What IPv6 address should be assigned to a sliver (static or
> autoconf'd)?

For 1) the consensus so far was that it is cleaner/better to have the
vserver root context autoconf an IPv6 address per sliver. For example, one
could do this by overloading the EUI-64 bit value used by IPv6 to autoconf a
machine.  Specifically, the lower 64 bits of an EUI-64 autoconf'd IPv6
address is constructed by a combination of the 48bit MAC address + a special
16bit FFFE value.  E.g., suppose your MAC address is 1234:5678:9abc then the
EUI-64 IPv6 address component of this is ::1234:56FF:FE78:9abc (notre the
FF:FE embedded in the middle there).  Since the sliver's ID (xid) value is a
15-bit value, we can replace the upper 15bits of the 16bit FFFE value with
the xid.

An alternative approach would be for PlanetLab to apply for its own IEEE
assigned company ID for the 48Bit MAC address.  This appears to have been
the approach that VMware and Xen have taken.  I don't know how they select a
unique 24bit value per virtual machine -- probably using some random key.
If that is the case, I suppose they then rely on IPv6's Duplicate Address
Detection in case two virtual machines select somehow arrive at the same
48bit MAC address.   Well, we could use this approach, too.  In fact, I am
not sure of the legality of this, but I suppose we could just leverage the
VMware/Xen assigned company ids and use those until (if ever) PlanetLab gets
it own ethernet 24bit company id.

Marc