Monthly Archives: February 2009

For some truly unknown reason, Cisco’s devices still have support for “small servers” or “simple services”. Examples of these include echo, chargen, daytime and discard.  An attacker could possibly start a denial of service attack (DoS) against one or more network devices with those configured.  In this case; echo and chargen are to blame by [...]

Dynamic Trunking Protocol (DTP) is a standard feature of Cisco switches and allows two switches to dynamically configure interfaces interconnecting each other to be trunked ports.  DTP has 5 modes; Auto (default), On, Off, desirable and nonegotiate.  These 5 modes all have a purpose.  I have layed out the groundwork below: auto – The default [...]

I was working on a client’s network tonight and thought of about 10k topics to blog about.  All the commands on Cisco routers and switches.  The purpose of this would be to help remind me that the basics are not good enought and also expand your mind on what a command does, how to use [...]