[radvd-devel-l] Re: radvd-devel-l digest, Vol 1 #31 - 2 msgs

radvd-devel-l@litech.org radvd-devel-l@litech.org
Tue, 11 Jun 2002 23:31:33 +0530

On Tue, 11 Jun 2002 Sourajeet.Mohanty@lntinfotech.com wrote:
> I have some Queries regarding IPv6 Network Prefixes advertised by routers
> using radvd:

These question seem to be in no way related to radvd.

> 1) As in each link the prefixes advertised will be different from ech
> other, and suppose I have one network prefix with me.           Then how
> it possible to know on which link the prefix was advertised ?
> 2)  How to differentiate between network prefixes advertised on different
> links ? I mean, How one link is differentiated with another based on the
> prefixes advertised by routers on those links?

I don't understand what you mean. Elaborate.

(I'm assuming you're not trying to advertise the same prefix on different

==> Your assumption is correct.

> 3) How the TLA, NLA , SLA are formed in the prefixes ? How the prefixes
> formed based on those ids ? Is those ids are unique for a link then How
> different prefixes are formed based on those ids ?

TLA/NLA/SLA no longer exist.  The prefix has the "top-part" (first 48
bits), the "site-part" (the next 16 bits) and "interface-ID part" (last 64

Let me make myself clear:

Now suppose M1 is a router on which i want to run radvd and it has two
interface - eth0 & eth1. I want to advertise some Global prefixes on both
the interface. I want to make two different networks on eth0 & eth1.
Now as u said Prefix has "top-part" and "site-part".
So for a particular network the "top-part" and "site-part" will be fixed.
And then we cannot have more one prefix on that network, but IPv6 says one
network can have more than one prefixes so that one node can have more than
one Global unicast addresses.
Then what should be in the "top-part" and "site-part" for a particular
network so that it can be differentiated with the prefixes from other
network ??
What prefixes shall I advertise on eth0 & eth1 so that i can form two
different networks on those interfaces ?
Suppose i am advertising the following prefixes:
Does those two set of prefixes make two different network ??
If not then what shall i advertise to make them different ??

Could u please guide me how to form network prefixes for two different
networks ??