BGP LB with failover

Can someone hepls me with BGP config?

Scheme:
250Mbit/s
R1========================R2
100 Mbit/s

I want to make Loadbalancing with failover per prefix if it is possible.

R1 and R2 are conneced with 2 lines. First 250 Mbit and second is 100 Mbit/s

Thanx

Dave

You will have to prepend as path for your advertised prefixes. And adjust local pref for incoming prefixes.
You can start by looking at this example
http://wiki.mikrotik.com/wiki/Manual:Simple_BGP_Multihoming