[nsp] Load sharing over unequal bandwidth lines using CEF

[Harold Ritter]

Piotr,

At 03:15 PM 6/2/2003 +0200, Piotr Marecki wrote:
>----- Original Message -----
>From: "Harold Ritter" <hritter at cisco.com>
>To: "Earl Zmijewski" <eez at fluent.com>
>Cc: <cisco-nsp at puck.nether.net>
>Sent: Monday, June 02, 2003 2:30 PM
>Subject: Re: [nsp] Load sharing over unequal bandwidth lines using CEF
>
>
> > Earl,
> >
> > This is not CEF but routing protocol related. To do unequal cost path load
> > balancing you need a routing protocol that supports it. Currently, Eigrp
> > and BGP (Link bandwidth feature) support it.
> >
>
>
>When it comes to forwarding it is CEF related .

CEF only reflects what is set by the routing protocol ;o)

>  If i am right , to
>loadbalance CEF has internal data structure
>of 16 entries and hashing function chooses one of the 16 entries per
>flow/per packet.

The distribution that CEF does over the 16 entries is based on the traffic 
share count taken from the RIB, which for routing protocols other than 
Eigrp or BGP will be 1 for all equal cost path entries.

>So unless hashing function isn't
>something complicated you cant obtain all possible ratios .

Right. The ratio will be established on the base of 16.

>Also one can do unequal load-balancing using TE tunnels.

Absolutely.



>regards
>
>Piotr Marecki
>
>
>
>_______________________________________________
>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>http://puck.nether.net/mailman/listinfo/cisco-nsp
>archive at http://puck.nether.net/pipermail/cisco-nsp/

Harold Ritter, CCIE 4168
Advanced Services - SP East
Cisco Systems
1414 Massachusetts Avenue
Boxborough, MA 01719 USA
Phone: 978 936 1431
Fax: 978 936 1431
Cisco Systems- "Empowering the Internet Generation."