At 11:39 1/30/96, Iljitsch van Beijnum wrote:

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At 6:09 1/29/96, Alex.Bligh wrote:

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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've

Suppose 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? ;-)

Unless you announce both the /16 (or 19) AND the /22, they are not multi-homed but only single routed (with some fallback for those who see the /22 announcement). Anyone who gets the unfiltered /22 announcement will used the other provider (so long as that provider is up) while you get used only by those who get a filter routing (and as fallback when the other provider goes down).