[j-nsp] BGP Damping

[Khawaja, Kashif]

Hi All:

Had a question about how damping policies can be written. 
########################################################################
##
Does a damping policy "have" to be of the following shape or form i.e.
prefix-lists/route-filters defined in the from parts of the terms?
########################################################################
##

Borrowed from CYMRU's webpage for example:

[edit policy-options] 
policy-statement damping {
/* Do NOT dampen DNS root-servers */
    term 1 {
        from {
            prefix-list root-servers.net;
        }
        then {
            damping damp-none;
            /* jump to next policy called */
            next policy;
        }
    }
/* Dampen according to prefix length.  */
term 2 {
    from {
      /* Smallest penalty for /21 and smaller */
            route-filter 0.0.0.0/0 upto /21 damping damp-short;
      /* Medium penalty for /22 to /23 */
            route-filter 0.0.0.0/0 upto /23 damping damp-medium;
      /* Highest penalty for /24 and larger */
      route-filter 0.0.0.0/0 orlonger damping damp-long;
        }
        then {
            next policy;
        }
    }
} 

################################################################
OR CAN IT ALSO LOOK LIKE THE NESTED POLICY BELOW?
################################################################

policy-statement damping2 ( 
term not-damp {
    from policy no-damp; 
    then damping do-not-damp;
}
term 24-and-bigger {
    from policy 24-longer;
    then damping damp-24;
}
term 22-and-23 {
    from policy 22-to-23;
    then damping damp-22;
}
term regular-damp {
    then damping default-damp;
}
}

show policy-options policy-statement 24-longer 
term one {
    from {
        route-filter 0.0.0.0/0 upto /23 next term;
        route-filter 0.0.0.0/0 orlonger;
    }
    then accept;
}
term two {
    then reject;
}

show policy-options policy-statement 22-to-23    
term one {
    from {
        route-filter 0.0.0.0/0 upto /21 next term;
        route-filter 0.0.0.0/0 orlonger;
    }
    then accept;
}
term two {
    then reject;
}

show policy-options policy-statement no-damp
term one {
    from {
        route-filter 1.1.1.0/24 exact accept;
    }
    }
term two {
    then reject;
}

OF COURSE, add "then accept" or "then next policy" DEPENDING ON WHERE IN
THE LINE OF POLICIES THIS POLICY IS APPLIED TO THE NEIGHBOR. 

Thanks.
-Kashif.