Network Documentation Series: Port Mapping

In this post, I will be doing a brief commentary on creating and maintaining a physical port mapping spreadsheet. A port mapping spreadsheet is useful for keeping track of used/available ports on your network equipment,…


Network Documentation Series: Physical Diagram

This article is a quick tutorial for creating and maintaining a physical network diagram. I prefer to use the term “physical” instead of “L1” because it is more easily understood by somebody unfamiliar with the…


Network Documentation Series: Preamble

This post is the first in a series of articles tackling the topic of creating and maintaining proper network documentation. Each article will include a file which can be downloaded and used as a template…


Cisco NAT Cheat Sheet

I’ve always had a difficult time when attempting to remember how to implement the different types of NAT available on ASA and IOS devices. It doesn’t help that between the two device families, there are…


CDP on an ASA (To Some Extent)

If you have been in the Cisco networking world for any length of time then you have probably used CDP (Cisco Discovery Protocol) or LLDP (Link Layer Discovery Protocol) at least once or twice to…


SDN – Is Software Fast Enough

During a VMWare NSX training class a while back, a question was raised to the instructor concerning the throughput that is possible on a NSX distributed switch or router (two components that are crucial to…



When it comes to internet redundancy, the Cisco ASA family of firewalls can be very flexible in how they can be configured to provide that highly available connection. You can even host highly available internet-facing…


VRF-Lite, MPLS, and Null Routing

In the field of IP routing, the practice of using null routes (A.K.A. “Black-Hole Routes”) has always had a place. Null routes are often used for DOS mitigation, loop prevention, routing stability, and route summarization….


Exchange 2010 Multi-Tenancy

I recently realized that you really get what you pay for with free email services (Gmail, Yahoo, etc…). No unified contacts synchronization or calendar management. And POP/IMAP? Way too 1980’s. We have better technologies and…