Getting started with Network Packet Generators

bit blaster

A friend of mine has just ordered a shiny new packet generator for his network lab. I’ve spent some time working as a QA engineer in a network lab and wanted to share some advice.

You can purchase stateful and stateless packet generators from major vendors like Spirent, IXIA or Agilent. If you just need to test throughput, latency or loss, a stateless packet generator will do the trick. The test hardware will use an ASIC to produce line-rate 10G traffic or higher. The Cisco Enterprise Testing Book calls this a ‘bit-blaster’ which I love. In the wrong hands it can also be a ‘network-melter’.  Continue reading

Test – Throughput alchemy using a snake topology

Sometimes it’s best not to trust network vendor datasheets.  Nothing quite beats a controlled test of a network device in your lab with your config and your required features. But if you want to load test multiple ports on your 10G device-under-test (or DUT), then things can get very expensive, very fast.  In this post I’ll show a test topology that will help you turn 10Gbps of test traffic into 640Gbps or more.

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Tester not included

A few years ago, I had the chance to attend an IXIA training course in our Dublin office. I had seen the time-suck of network test gear before.  So I said,  “I’m not spending a week trying to learn a test-set.  It’ll be cool, but what’s the point. I won’t get the time to apply those skills, then I’ll forget, and it will be a wasted week.”  I declined the training.

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Get more juice from your network lab

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We have a network lab?

Spirent presented their new lab-management software, called iTest Lab Optimizer, at network field day 4 recently.  Their product name isn’t catchy, but it is very descriptive and addresses a market need.  The simple fact is that most lab networks don’t get optimised to their full potential for some of the following reasons:

  1. Nobody knows what is in the lab (or that one exists) – Inventory Management
  2. The availability of the lab devices is unknown  – Availability and scheduling
  3. The patching status of the devices is uncertain – Fixed undocumented patching.
  4. Setting up your device-under-test is hard and takes time,  so you try to prevent other users from mangling your config. – DUT config management