Netmasks and BGP
Your network must be a /24 or larger to route BGP, but what if it's larger? It is preferable to announce as few blocks as possible in order to reduce the size of the global routing table. Multiple consecutive "class C" blocks might very well be a legitimate network block. You probably don't want to break out your calculator and transform all your network blocks into binary to find out though! Here are some hints to determine whether a block of IP addresses is a legitimate single block.
Remember that network blocks are issued in multiples of two. This holds true all the way up the scale, including the larger network numbers. This means that each legitimate block must be a multiple of two. If a block is actually legitimate, it will ...
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