March 2009
Beginner to intermediate
144 pages
3h 13m
English
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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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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.