Tag: programming

Welcome to the second, and final, part of blog posts showing how to use Python to work with IP addresses. In part one we learned how ipaddress library can help us when working with IP addresses. We then learned about Address and Network objects and operations we can perform on them. Here I'll present Interface object, and its methods, before moving onto module level functions. After that I'll show how we can compare and sort ipaddress objects. We'll finish our journey with the module by talking about validation and exception handling. Working with IP addresses in Python series: Working with...

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If you work with computer networks sooner or later you will have to learn how to efficiently work with IP addresses and networks. As you probably guessed from the title of this post, we'll be learning how to create, modify and perform operations on IP objects using Python. Having to manipulate IP objects is common enough that Python ended up with a built in library dedicated to these tasks. It's name is... you probably guessed it, the name of the module is ipaddress. That's right, all you have to do to start working with IP goodness is one line,import...

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In this blog post I want to share, and talk about, Python program I wrote to solve problem of filtering out child prefixes. Contents Problem description Solution Naïve algorithm Patricia tree aka binary radix tree Python implementation Load testing Module and cli version Closing thoughts References Problem description So what exactly is the problem we're trying to solve? Imagine that you have a group of prefixes, assigned to servers, or clients, and you want to only keep prefixes that are not subnets of any other prefix. This could be because of your routing requirements or because you want to minimise...

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I'm sure many of you had to compute summary network given a number of subnets. It's one of those rare occasions when you have to dust off binary maths skills that you had to pick up while learning ip address subnetting. In this blog post I want to discuss related problem, namely working out the largest prefix length needed to encompass provided prefix lengths. I realise it's a mouthful so I'll show some examples before moving onto solution and corresponding Python code. Contents Problem description Examples Solution and algorithm Python implementation Example usage GitHub repository with the source code Problem...

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Nested loops, we all love them. Or do we? Five levels of indentation later you are not so sure. Your code starts to look ugly and you wish there was another way. Fortunately there is! One of the functions provided by itertools, product(), can replace your loops with a function call. So what is itertools.product? It's a function that takes a number of iterables and returns their Cartesian product, or in simpler terms, all ordered tuples with elements coming from each of the iterables. Product of [1, 2] and ['a', 'b', 'c'] would result in tuples: (1, 'a'), (1,...

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