Book Image

Mastering Python Networking - Third Edition

By : Eric Chou
Book Image

Mastering Python Networking - Third Edition

By: Eric Chou

Overview of this book

Networks in your infrastructure set the foundation for how your application can be deployed, maintained, and serviced. Python is the ideal language for network engineers to explore tools that were previously available to systems engineers and application developers. In Mastering Python Networking, Third edition, you’ll embark on a Python-based journey to transition from traditional network engineers to network developers ready for the next-generation of networks. This new edition is completely revised and updated to work with Python 3. In addition to new chapters on network data analysis with ELK stack (Elasticsearch, Logstash, Kibana, and Beats) and Azure Cloud Networking, it includes updates on using newer libraries such as pyATS and Nornir, as well as Ansible 2.8. Each chapter is updated with the latest libraries with working examples to ensure compatibility and understanding of the concepts. Starting with a basic overview of Python, the book teaches you how it can interact with both legacy and API-enabled network devices. You will learn to leverage high-level Python packages and frameworks to perform network automation tasks, monitoring, management, and enhanced network security followed by Azure and AWS Cloud networking. Finally, you will use Jenkins for continuous integration as well as testing tools to verify your network.
Table of Contents (18 chapters)
16
Other Books You May Enjoy
17
Index

Access lists

The network access lists are usually the first line of defense against outside intrusions and attacks. Generally speaking, routers and switches process packets at a much faster rate than servers by utilizing high-speed memory hardware such as ternary content-addressable memory (TCAM). They do not need to see the application layer information. Instead, they just examine the layer 3 and layer 4 headers and decide whether the packets can be forwarded. Therefore, we generally utilize network device access lists as a first step in safeguarding our network resources.

As a rule of thumb, we want to place access lists as close to the source (client) as possible. Inherently, we also trust the inside host and distrust clients beyond our network boundary. The access list is therefore usually placed on the inbound direction on the external facing network interface(s). In our lab scenario, this means we will place an inbound access list at Ethernet2/1 on nx-osv-1, which is directly...