| > Perfectly aggregated networks are star-shaped. | | No. They are tree shaped. It seems pretty difficult to have all elements in a network except one have only a default route if you have a tree shape, assuming you don't mean a 3-node network... | > This is a result of the CIDR addressing architecture and is | > INDEPENDENT OF THE NUMBER OF BITS IN AN ADDRESS. | | I disagree, if insted we didn't aggregate into /19s or /20s but into /22s | and /23 there would be less unoptimum routing and larger (less scalable) | route tables. Yeah, and if you deaggregate from /[overhead]s into /[overhead+2 or 3] in any length CIDR routing system, you get 4 or 8 times the number of prefixes, and make some people happy that they get more optimal routing and make some people unhappy that they have to bear the extra dynamism. In the interest of obviousness, "overhead" is the number of bits necessary to identify a unicast address, and if you want to use a larger value (like 19 or 20) just for fun, you get the same number of potential prefixes whether your field is 32 bits or 128 bits or 2³² bits. Sean. (g'night)