Subject: AODV draft version 08

From: Yves Prelot <[email-masked]>
Date: Mon, 26 Mar 2001 15:56:01 +0200

Hello,

I believe there is a problem with one of the modification introduced by
version 08 over version 07.

(a) paragraph 8.5 : Forwarding Route Replies
"If a new route is created or the old route is updated...
 ...the hop count is the Hop Count in the RREP message plus one"

(b) paragraph 8.4.2. Route Reply Generation by an Intermediate Node
"The intermediate node places its distance in hops from the
   destination (indicated by the hop count in the routing table) plus
   one in the Hop Count field in the RREP"

(c) paragraph 8.4.1. Route Reply Generation by the Destination
"The destination node places
   the value zero in the Hop Count field of the RREP"

(d) paragraph 8.5 : Forwarding Route Replies
"If the current node is not the source node as indicated by the Source
IP Address in the RREP message...
 ...and then forwards the RREP towards the source with its Hop Count
incremented by one"

Lets applys this in the following configuration :

A ----- B ----- C

1) B asks a route for C. C answers, puts 0 as hop count (c). B receives
the answer and puts 1=0+1 into it's table (a)

2) A asks a route for C. B answers, puts 2=1+1 as hop count (b). A
receives the answer and puts 3=2+1 into it's table (a)

3) Suppose that B doesn't know C now. A asks a route for C. C answers,
puts 0=0 as hop count (c). B receives the answer and puts 1=0+1 into
it's table (a). B then sends the RREP with 1=1+0 in the hop count (d). A
receives the answer and puts 2=1+1 into it's table (a).

How come that the result is not the same for A in case 2 and 3 ? In
particular, the hop count is wrong for A in case 2. I believe that the
modification in paragraph 8.4.2 is erroneous.

Am I right or did I fail to see something ?

Thank you,

Yves

---

From: "Samir R. Das" <[email-masked]>
Date: Tue, 27 Mar 2001 11:22:25 -0500

I sent this email yesterday. Somehow it did not show up in the mailing
list.

Samir

-----Original Message-----
From: Samir R. Das [mailto:[email-masked]]
Sent: Monday, March 26, 2001 7:06 PM
To: Yves Prelot
Cc: [email-masked]
Subject: RE: AODV draft version 08

Yves,

You are right. The para in 8.4.2 should read:

"The intermediate node places its distance in hops from the
destination (indicated by the hop count in the routing
table) in the Hop Count field in the RREP"

We will make this correction in the next round.

Samir

> -----Original Message-----
> From: [email-masked]
> [mailto:[email-masked]]On Behalf Of Yves Prelot
> Sent: Monday, March 26, 2001 8:56 AM
> To: [email-masked]
> Subject: AODV draft version 08
>
>
> Hello,
>