Since Thomas suggested some similar text, could folks please reply to
this email from Josh.
Thanks.
Hemant
________________________________
From: Josh Littlefield (joshl)
Sent: Wednesday, December 05, 2007 2:08 PM
To: Hemant Singh (shemant)
Cc: Suresh Krishnan; [EMAIL PROTECTED]; IETF IPv6 Mailing List
Subject: Re: Here is the reference to 6.3.4 text that is ambigious text
It is not crystal clear, but my impression is that this paragraph is
saying:
Default sending behavior is send to default router.
Reception of L=1 signals on-link (can use ND to send directly)
Reception of L=0 is no-op.
Because L=0 is no-op, if one considered the prefix on-link due to prior
L=1, then prefix is still on-link.
If one did not consider the prefix on-linke due to prior L=1, then
retain default behavior.
It might be clearer to have said that default assumption is that all
prefixes are off-link, and this means send to default router. Only
reception of L=1 can change that for any specific prefix. A prefix with
L=0 does not change off-link, or on-link status of prefix, and is the
same as omitting the prefix entirely from the RA, from the point of view
of on-link determination.
Hemant Singh (shemant) wrote:
The summary from this section snipped from 6.3.4 of RFC 4861 is
saying no on-ink information does not mean off-link. So why is the text
is red where is says, send traffic to default router being said because
the text in red signals off-link behavior. Why is this paragraph not
ambiguous?
Prefix Information options that have the "on-link" (L) flag set
indicate a prefix identifying a range of addresses that
should be
considered on-link. Note, however, that a Prefix Information
option
with the on-link flag set to zero conveys no information
concerning
on-link determination and MUST NOT be interpreted to mean
that
addresses covered by the prefix are off-link. The only way
to cancel
a previous on-link indication is to advertise that prefix
with the
L-bit set and the Lifetime set to zero. The default behavior
(see
Section 5.2) when sending a packet to an address for which no
information is known about the on-link status of the address
is to
forward the packet to a default router; the reception of a
Prefix
Information option with the "on-link" (L) flag set to zero
does not
change this behavior. The reasons for an address being
treated as
on-link is specified in the definition of "on-link" in
Section 2.1.
Prefixes with the on-link flag set to zero would normally
have the
autonomous flag set and be used by [ADDRCONF].
Hemant
________________________________
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email protected]
Administrative Requests:
https://www1.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
--
=====================================================================
Josh Littlefield Cisco Systems, Inc.
[EMAIL PROTECTED] 1414 Massachusetts Avenue
tel: 978-936-1379 fax: 978-936-2226 Boxborough, MA 01719-2205
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email protected]
Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------