Subject: How PING6 works

From: Rajesh N <[email-masked]>
Date: Thu, 26 Sep 2002 13:38:02 +0530

Hi group,

I am a bit confused about how ping6 works in an ethernet...

Assume I have a simple ethernet lan, with few private subnets, say 
192.168.10.0 and 192.168.20.0, connected by a local gateway (G) with 
interfaces 192.168.10.5 and 192.168.20.5. Now, I have a PC each on these 
subnets, say with IPV4 addresses (A)192.168.10.15 and (B)192.168.20.15 
configured with IPV6 linux, so that each of them have a link local IPV6 
addresses starting with fe80:

Now when I do a ping6 from A like, 'ping6 -I eth0 
link-local-IPV6address-of-B' I get a reply. How does this work?

My understanding is that the ICMPV6 datagram containing the echo  request 
of ping program is put in an IPV6 datagram, which is put in an ethernet 
frame and send down to G. But for G's routing module to understand the 
destination IPV6 address of B, should there be any special protocol running 
on it?

Sorry if my queston is confusing...Pls direct me to a good explanation of 
how IPV6 works in an ethernet..

Thanks in advance
Regards,
Rajesh N

--------------------------------------------------------------------
IETF IPng Working Group Mailing List
IPng Home Page:                      http://playground.sun.com/ipng
FTP archive:                      ftp://playground.sun.com/pub/ipng
Direct all administrative requests to [email-masked]
--------------------------------------------------------------------

---

From: Robert Elz <[email-masked]>
Date: Thu, 26 Sep 2002 16:10:01 +0700

Date:        Thu, 26 Sep 2002 13:38:02 +0530
    From:        Rajesh N <[email-masked]>
    Message-ID:  <4.3.2.7.1.20020926132525.00db1c20@blaze>

  | Now when I do a ping6 from A like, 'ping6 -I eth0 
  | link-local-IPV6address-of-B' I get a reply. How does this work?

If you know how this works if it were IPv4 instead of IPv6, then
you also know how it works (in essence) for IPv6, there are no
differences of significance (only details).

If you don't know how it works for IPv4, there are lots of good text
books available (and some not so good, but never mind) that will
explain it all.

kre