Note: You should read about Content Addressable Memory (CAM) before reading this post. Today’s networking hardware operates a Layer 2, Layer 3 and Layer 4 of the OSI model. The device might switch Ethernet frames, route IP packets and implement filters based on the TCP segments. A MAC Address is always an exact match and […]
Content-addressable memory (CAM) is silicon chip architecture that is purpose-built for extremely fast but very specific type of memory lookups.
The terms routing, switching, forwarding and bridging have different meanings that have changed over time.
This article provide a practical and workable definition of “What Is a Network Service ?”
Containers virtualize at the operating system level, Hypervisors virtualize at the hardware level. Hypervisors abstract the operating system from hardware, containers abstract the application from the operation system. Hypervisors consumes storage space for each instance. Containers use a single storage space plus smaller deltas for each layer and thus are much more efficient. Containers can boot and be […]
Notes on the CheckPoint firewall clustering solution based on a review of the documentation in August 2014.
I was asked to explain the concept of abstraction in software and IT infrastructure to a group of people who had limited technical capability. It needed to be simple and relevant to every day people.
Here is what I came up with.
Short version – I’d like you to read just these if nothing else.
- A data centre uses a lot of electricity. It’s dangerous.
- Just in case you didn’t pay attention – Electricity is really dangerous. Right, can we move on ?
- You should be scared of being electrocuted. That will keep you safe.
- When electrocution happens, the muscles in your limbs contract. This causes arms and hands to wrap around or clench objects.
- Someone who is being electrocuted can’t let go because of this
- If you touch a person being electrocuted, you will get an electric shock too, and may also be injured.
- The BEST thing to do is to turn the power off.
- Know where the power kill switch is for Data Centre. Or at least the breaker for the area that you are in.
- Don’t work in the Data Centre alone.
- Learn resuscitation. People who have been electrocuted are likely to have breathing problems and heart failure.
People shouldn’t die at work. Think seriously about going home everyday and what you can do to make that happen.
Most engineers think that cable is simply plug and play. And mostly, that true. In recent years, Ethernet standards and manufacturing Here are 20 things that Network Engineers have forgotten or don’t know about network cabling in a two part series on things I have learned in twenty years of looking after networks.
BPDU Guard and Root Guard are enhancements to Spanning Tree Protocol (STP) enhancements that improve the reliability of the protocol to unexpected events ad are primarily to ensure design enforcement ( integrity / security). There they must configured in specific locations in the networks.