IP Fragmentation Lab with Vagrant

Recently, I had a need to understand IP fragmentation better, so I built a lab to experiment with.  I wanted it to be easy to setup, and built in a way that is repeatable by others, so I designed automation to stand it up with virtual machines in a hypervisor. The lab network topology is shown in Figure 1.

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Figure 1 – Network Diagram for IP Fragmentation Lab

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What is a Network Traffic Flow? (Part 2)

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Network traffic flows (flows) are useful for building a coarse-grained understanding of traffic on a computer network. Flows provide a convenient unit for the measurement and/or treatment of traffic.

Following on from What is a Network Traffic Flow?, this second post delves into Internet layer flow considerations. Previously, we found that the definition of a flow is mainly arbitrary, primarily driven by the capabilities of hardware/software, and the use cases. We now delve further into the considerations around specific features and behaviours of IP.

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Figure 1 – Where this Blog Post fits in the Internet Protocol suite Continue reading