Book Image

Python Network Programming

By : Abhishek Ratan, Eric Chou, Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker
Book Image

Python Network Programming

By: Abhishek Ratan, Eric Chou, Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker

Overview of this book

This Learning Path highlights major aspects of Python network programming such as writing simple networking clients, creating and deploying SDN and NFV systems, and extending your network with Mininet. You’ll also learn how to automate legacy and the latest network devices. As you progress through the chapters, you’ll use Python for DevOps and open source tools to test, secure, and analyze your network. Toward the end, you'll develop client-side applications, such as web API clients, email clients, SSH, and FTP, using socket programming. By the end of this Learning Path, you will have learned how to analyze a network's security vulnerabilities using advanced network packet capture and analysis techniques. This Learning Path includes content from the following Packt products: • Practical Network Automation by Abhishek Ratan • Mastering Python Networking by Eric Chou • Python Network Programming Cookbook, Second Edition by Pradeeban Kathiravelu, Dr. M. O. Faruque Sarker
Table of Contents (30 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
Index

Converting integers to and from host to network byte order


If you ever need to write a low-level network application, it may be necessary to handle the low-level data transmission over the wire between two machines. This operation requires some sort of conversion of data from the native host operating system to the network format and vice versa. This is because each one has its own specific representation of data.

How to do it...

Python's socket library has utilities for converting from a network byte order to host byte order and vice versa. You may want to become familiar with them, for example, ntohl()/htonl().

Let us define the convert_integer() function, where the ntohl()/htonl() socket class functions are used to convert IP address formats.

Listing 1.5 shows integer_conversion as follows:

#!/usr/bin/env python 
# This program is optimized for Python 2.7.12 and Python 3.5.2. 
# It may run on any other version with/without modifications. 
 
import socket 
 
def convert_integer(): 
    data...