From: gladston@br.ibm.com
Date: Tue Aug 16 2005 - 17:16:42 GMT-3
Hi,
I just remember that Solies talks about this subject. Her books has an
example using both, ppp multilink and dialer load-threshold at the same
time:
ppp multilink
dialer load-threshold ...
I have heard that 'ppp multilink link minimum...' works better. But on
tests, both have their problems, specially when config are changed,
sometimes requiring a reload on the router. (that just happened today when
I was testing to check this threat...after removing 'dialer
load-threshold' and configuring 'ppp multilink' and 'ppp multilink
minimum...' the ISDN stop working, just displaying that there was no free
channel to dial)
I am not sure yet what happens if just configuring 'dialer load-threshold'
concerned to the distribution of packets along the two channels.
With ppp multilink it is clear that IOS fragments packets, split them over
the two channels, and the remote router reassembles them.
But how packet are sent across the two channels when using only dialer
load-threshold?
Any feedback appreciated.
Cordially,
------------------------------------------------------------------
Gladston
----- Forwarded by Alaerte Gladston Vidali/Brazil/IBM on 16/08/2005 17:08
-----
Alaerte Gladston Vidali/Brazil/IBM
16/08/2005 17:03
To
"Arun Arumuganainar" <aarumuga@hotmail.com>
cc
ccielab@groupstudy.com, nobody@groupstudy.com
Subject
Re: Re: config - ISDN B-Channel 2 links - up ---> Doubt
Hi Arun,
Sorry, I made a mistake. When using 'dialer idle-threshold.." there is two
channel, not two entries on the routing table.
If I am not mistaken, Multilink PPP load balance using both channels,
while BOD does not get load balancing. The second channel is used only
when the first
is 'full'.
I hope we get more feeback on this.
==================================================================================
Bandwidth on demand (BOD) is a Cisco proprietary implementation that
allows the aggregation
of multiple B channels into a single logical connection. This
implementation is widely used in
Cisco-centric networks
The implementation of Cisco's BOD solution is accomplished through the
dialer load-
threshold command
Multilink PPP is a specification that enables the bandwidth aggregation of
multiple B channels
into one logical pipe. Its mission is comparable to that of Cisco's BOD.
More specifically, the
Multilink PPP feature provides load-balancing functionality over multiple
wide area network
(WAN) links, while providing multivendor interoperability, packet
fragmentation and proper
sequencing, and load calculation on both inbound and outbound traffic
Cisco's implementation of Multilink PPP supports the fragmentation and
packet sequencing
specifications in RFC 1717. Multilink PPP enables packets to be fragmented
and the fragments
to be sent (at the same time) over multiple point-to-point links to the
same remote addres
==================================================================================
This discussion says:
===========================================================
quoted from
http://www.groupstudy.com/archives/ccielab/200406/msg00697.html
int bri0
dialer load-threshold 10
and
int bri0
ppp multilink
ppp multilink load-threshold 10
Both will add a second channel when the load reaches 10/255, however in
the
first case you don't really have a ppp multlink, only two seperate
channels.
=======================================================================
Thanks,
Alaerte
"Arun Arumuganainar" <aarumuga@hotmail.com>
Sent by: nobody@groupstudy.com
13/08/2005 01:49
Please respond to
"Arun Arumuganainar" <aarumuga@hotmail.com>
To
Alaerte Gladston Vidali/Brazil/IBM@IBMBR, <ccielab@groupstudy.com>
cc
Subject
Re: Re: config - ISDN B-Channel 2 links - up ---> Doubt
Hmmm ... I am not an Expert on ISDN . But this is what my understanding
!!!
There are two ways of configuring Bandwidth aggrigation 1) PPP Multilink
and 2) BOD . Functionality wise both are exactly the same .
Two Channels to same destination
1 Route in the routing table .
But the difference between them is that PPP multilink is standard fromat
while BOD is cisco properitary !!!
Note : BOD is used when both the ends are CISCO !!! If you are dialing in
to
non cisco devices PPP multilink is the only option
Thanks and Regards
Arun
----- Original Message -----
From: <gladston@br.ibm.com>
To: <ccielab@groupstudy.com>
Sent: Friday, August 12, 2005 11:46 PM
Subject: Re: Re: config - ISDN B-Channel 2 links - up ---> Doubt
> Arun,
>
> Would you agree with Shanky?
>
> I am not sure if you stating a different point.
>
> Configuring 'dialer load-threshold..' without 'ppp multilink':
> -- two channels to the same destination
> -- two entries on the routing table
>
> On the other hand, configuring 'dialer load-threshold..' with 'ppp
multilink':
>
> -- two channels to the same destination
> -- one entry on the routing table
>
> Could you think about an example when 'dialer load-threshold' without
ppp
multilink would be used?
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:01:19 GMT-3