Re: Router Solicitations

[Niklas Neumann <niklas.neumann@cs.uni-goettingen.de>]

Thank you for your response. Just to make it perfectly clear to me:
How long is a unicast address valid?
- Until the host gets disconnected from the link?
- Until some timeout expires (e.g. Router Lifetime, DHCP Lifetime)?
- Some other trigger (e.g. L2 trigger)?

For example: If a host gets disconnected (e.g. wire gets pulled out) 
from a link and shortly after it gets reconnected. Does it send the 
Router Solicitation with its previous address or the unspecified address?

Thank you so much for answering.
Best regards
  Niklas


JINMEI Tatuya / 神明達哉 wrote:
> At Tue, 10 Jun 2008 11:25:09 +0200,
> Niklas Neumann <niklas.neumann@cs.uni-goettingen.de> wrote:
>
> > I have a question regarding RFC 4861, Section 6.3.7. "Sending Router 
> > Solicitations". The RFC states that when a host is sending a Router 
> > Solicitation, "the IP source address is set to either one of the 
> > interface's unicast addresses or the unspecified address."
> >
> > So my question is
> > 1) when is a host supposed to set a unicast address and
> > 2) what qualifies as "one of the interface's unicast addresses?"
>
> My understanding is:
>
> 1) whenever it has a valid unicast address (i.e., almost anytime)
> 2) any valid unicast addresses that are proved to be unique assigned
>    to that interface
>
> > For example: Is an implementation supposed to remember the last address 
> > an interface had and to include this address in a Router Solicitation 
> > after the host attaches to a new link?
>
> No.
>
> ---
> JINMEI, Tatuya
> Internet Systems Consortium, Inc.


--
Niklas Neumann - University of Goettingen, Institute of Informatics
http://user.informatik.uni-goettingen.de/~nneuman1/
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