Aggregate multiple contiguous networks into a single supernet with the smallest matching prefix.
Supernetting (route aggregation) combines multiple contiguous networks into one larger summary route by finding the longest common prefix between the first and last network addresses. The result is a single CIDR block that encompasses all the original networks, reducing routing table entries.
Supernet prefix
prefix = number of common leading bits between first and last network
Networks aggregated
count = 2^(original_prefix - supernet_prefix)
Supernetting is used to reduce routing table size by summarizing multiple contiguous routes into one aggregate route. It's essential for BGP route announcements and any scenario where routing table efficiency matters.
Yes — only contiguous, properly aligned networks can be accurately summarized into a single supernet without inadvertently including address space that isn't part of the original set.