Route aggregration is an effort to
route smaller
prefixes via an aggregated larger prefix (
supernetting). The advantage is obvious: Many /24 networks, for example, could be aggregated to larger networks like /23, /22 or even bigger prefixes. For the Internet Registries (
RIRs and
LIRs) it is therefore necessary to follow a strict policy in assigning netblocks to
ISPs.
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