Bits, Bytes, & Radio Waves

A Journey Through Discovery

  • Point-to-Point Link

    Configure To configure a Point-to-Point link, you will configure the serial interface just like you would an Ethernet interface. In addition, you need to use the no shutdown command because interfaces are down by default on a router. The other difference is that you need to have a clocking mechanism in place. Clocking takes place…

  • EtherChannel

    EtherChannel is a way to provide redundant links and not be affected by Spanning Tree Protocol (STP). By design, when you connect multiple links to switches, STP will shut down the excess links to prevent loops. There is a Cisco version and an IEEE version. Cisco’s is called Port Aggregation Protocol (PAgP), and the IEEE…

  • Add and Remove VLANs on a Trunk

    Where access ports allow for only one data VLAN and one voice VLAN, a trunk port can carry one or more VLANs. Generally, you would use a trunk to connect switches together where you need to carry traffic. In some cases, you would configure a trunk port to connect to a server, such as a…

  • Assigning Switch Ports to VLANs

    Interfaces on Cisco switches can belong to two VLANs, one for data traffic and one for voice traffic. You set the interface to be an access port. This also turns off trunking and VLAN Trunking Protocol (VTP). Configure The following command will configure an access port. An access port is intended for data traffic. Switch#configure…

  • Default Virtual Local Area Network (VLAN)

    The default virtual local area network (VLAN) is 1 by default on any Cisco switch. It is a special VLAN in that it cannot be changed or deleted. It is a management VLAN that carries control protocols such as Cisco Discovery Protocol (CDP), VLAN Trunking Protocol (VTP), Port Aggregation Protocol (PagP), and Dynamic Trunking Protocol…

  • Link State Advertisements (LSA) Types

    Routers have to agree on certain parameters (such as timers and being on a common subnet) before they can become neighbors. After its neighbor routers are discovered, the router determines whether it should exchange routes with those neighbors. (If they decide to do so, they become adjacent.) If they are adjacent, they begin to exchange…

This is how it all started…

I started this site with the intent to aggregate as much information as possible in one place. I use this to record lessons learned or frustrating configurations I have experienced on the job or just tinkering (learning) and just couldn’t find a better resource available. I have tried to be as thorough and accurate as possible, but technology is rapidly evolving and every environment is different. I may miss things along the way and my setup most likely differs compared to yours.

I hope you find this site has some value to you.

Welcome to Bits, Bytes, and Radio Waves! 

If you have any questions or comments (or just want to give me a shout-out), please feel free to contact me!

Aaron Rombaut

Writer & Technologist