> > Currently I have 2 choices as
> >far as I can make out, give them a bit of my /19, break up my
> >nice aggregate and ensure loads of extra announcements (and that
> >probably none of them get routed by anyone applying prefix based
> >filtering), or give them a new /19 all of their own (you'veSuppose you have a customer that needs a /22 and they want to go
multi-homed. Suppose you give them that /22 out of your /19 or /16 you
got from the RIPE NCC. So they announce their /22 to you and to their
other provider. But you keep announcing your /19 or /16. So if anybody
were to filter the /22 announcement, your customer only suffers partial
loss of connectivity, since you are still announcing an aggregate of
their announcemnt (your original /19 or /16).Problem fixed. Anything else?
Yes, if you go down, or their line goes down to you, their multi-homing is
worthless.
Dave