Subject: RE: (ngtrans) I-D ACTION:draft-ietf-ngtrans-mech-04.txt

From: Richard Draves <[email-masked]>
Date: Wed, 16 Jun 1999 15:12:27 -0700

> I strongly believe tunnel "interfaces" should be allowed to have
> link-local addresses.  I actually believe it should be a MUST.

I disagree with the MUST. In some simple host implementations, a configured
tunnel does not correspond to an "interface" so it doesn't make sense to
require a link-local address. I agree that if you are doing routing with
configured tunnels, then it makes sense to have an "interface" corresponding
each configured tunnel and use link-local addresses.

Rich

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From: Jim Bound <[email-masked]>
Date: Thu, 17 Jun 1999 11:32:41 -0400

Rich,

>each configured tunnel and use link-local addresses.

So they you will not object at last call to a **SHOULD**?

thanks
/jim

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From: Erik Nordmark <[email-masked]>
Date: Thu, 17 Jun 1999 11:03:36 -0700 (PDT)

> each configured tunnel and use link-local addresses.

Rich,
You must mean something different than RFC 2460 when you say "interface".
It says:
   interface   - a node's attachment to a link.

   link        - a communication facility or medium over which nodes can
                 communicate at the link layer, i.e., the layer
                 immediately below IPv6.  Examples are Ethernets (simple
                 or bridged); PPP links; X.25, Frame Relay, or ATM
                 networks; and internet (or higher) layer "tunnels",
                 such as tunnels over IPv4 or IPv6 itself.

I can't read this other than a node's attachment to a tunnel over IPv4
is an interface.

Having said that implementations are free to implement tunnels any way
they please. For instance in BSD based systems here may or may not be
an ifnet structure associated with an IPv6 interface as defined above.

Is there an implementation problem to have link-local addresses
for tunnels?

   Erik