• In this, our final look at subnetting for now, we’ll examine more “find the subnet” problems, specifically those in which the subnet/host boundary lies within the second or third octets. Here is the powers of...

  • When we last left off we were discussing a Cisco NAC Framework scenario using a router. We had discussed the required configuration on the ACS server with ACLs and Attribute Definition Files. But we cannot just get away with only configuring the ACS server and NADs. You must also think about the hosts themselves. Our …   Read More

  • Back in the days of my youth, long, long ago, you could buy a car with no options—no fancy gee-qaws like leather upholstery, chrome wheels or even a radio. It rolled down the highway on...

  • In the previous editions of “Subnetting Shortcuts”, we solved various types of problems involving subnet masks. This time, we’ll look at some more complex cases, specifically those in which the subnet/host boundary lies within the second or third octets. But first, because our lives would be incomplete without it, here is the powers of two …   Read More

  • This time, we’ll use the shortcuts to solve some different types of problem. Instead of “find the mask”, this time the challenge is to “find the subnet”. Ready? Here’s the first problem: given a host address of 192.168.1.100 and a subnet mask of “/27”, determine the host’s subnet, the legal range of host addresses on …   Read More

  • Imagine that your up and coming career at paper products giant, Dunder-Mifflin, has led to your transfer to the Scranton, PA branch office. As you begin your first day of work in your new cubicle,...

  • In “Part 3”, we solved a subnet masking problem using shortcuts. This time, we’ll use the shortcuts to solve some additional problems. Here’s the first problem: given an address space of 172.16.1.0/24, divide the network...

  • My earlier post introduced the Cisco MeetingPlace solution that combines voice, video and web conferencing products that are housed within the customer’s private network, allowing for a lower cost of service and maximum security.Today we’ll go over the hardware platforms involved.   Read More

  • VLANs, as we discussed before, are used to create logical broadcast domains on switches. However this information needs to be synchronized between switches. Manual configuration can be tedious in a large scale network, so understanding...

  • Session Initialization Protocol (SIP) has clearly won as the leading IETF (internet engineering task force) standard which everyone is using to build Unified Communication applications. Now that the IETF has clearly defined this protocol and...