Posts By Timothy

Layer 2 Etherchannels, like any protocol, have their pro's and con's. Using layer 2 extends Spanning Tree Protocol (STP) over the Etherchannel, which can have adverse effects if you're not careful. Take for example the following topology crudely drawn in paint. SW1 is the STP  root bridge because it has the lowest bridge ID priority, so ports fa0/1 - 3 are designated…

Whilst the CCNA Security exam recommends disabling CDP in the production environment, I felt it didn't really explain in depth why it's a good idea. I mean sure, they mention that information about the device is leaked, but what information exactly is leaked? I ran a wireshark capture to find out!     I think the above screenshot of the CDP message explains it…

I recently purchased TCP/IP Illustrated, Vol 1: The Protocols (Highly suggest picking this up, it's extremely insightful, and I hope to learn a LOT more about TCP in the near future) and have been diving into networking as a whole a lot more; one such piece of text I read was on the Windows 'nslookup' tool I hadn't previously known much…

Below is an article I found (Got side tracked when looking up if CEF supports IPv6 or if it punts additional IP headers to the CPU - next post perhaps?) about how and when the Cisco IPS inspects traffic. I found IDS and IPS was one of the more interesting topics covered in the CCNA Security Curriculum, so much in…