Cisco Routers


While working at an ISP for two years, I often needed to give technicians a script with a standard config and instructions to change variables. I started with simple text files, then custom php scripts and finally worked with a friend to create 4peg.com.

 
(more…)


Cisco IP Communicator (CIPC) requires a sound card be installed on a PC in order to install or open. Under normal circumstances, this completely makes sense. However, in other circumstances (demos/labs), PCs are actually virtual machines … and do not have sound cards. In these situations, the engineers/trainers/etc are more concerned with dialing than actually hearing audio.

 

In order to use CIPC in a virtual machine, install Virtual Audio Streaming – a virtual sound card tool from ShiningMorning.com prior to installing CIPC. This software will install virtual audio drivers on your VM which allow CIPC to install and have dialing capabilities. Unfortunately, CIPC will still only allow one instance to run at a time…unlike IP Blue. I have tested this with VMWare ESXi but it may also work with other VMWare products.
 
(more…)


This tutorial will show you how to create or convert an existing audio file and save it in CCITT u-law – 8KHz 8bit Mono format for use in Cisco Unified Call Manager Express (CUCME), Cisco Unified Contact Center (UCCX) or Cisco Unity Express (CUE). This has always been an easy task with the Windows Sound Recorder that came with Windows XP. However, the sound recorder that comes with Windows 7 does not work the same.
 
(more…)


This tutorial will show you how to make config changes with a simple tcl script and invoke the script from an IOS menu. I was recently presented with a scenario where the FXO ports on a customer router were not receiving the supervisory disconnect from the PBX.
 
Until I find a way to auto reset the ports with EEM and the long call duration flag, the temporary solution is to create a menu where the customer can view call durations and reset voice-ports with a menu. The tcl script performs a ‘shut’ and ‘no shut’ on the voice port.
 
(more…)


This tutorial is a continuation of the virtual voice lab series. In this tutorial, you will add a dial-plan to the PSTN router that was added in the first part of the PSTN simulation lab. (more…)


Occasionally, I have run into the issue when turning up a PRI that ring back is not heard when placing an inbound call. Caller only hears silence until the called party answers. This seems to be more prevalent with smaller Telco’s who don’t have a lot of experience with PRIs.

(more…)


This tutorial is a continuation of the virtual voice lab series. Unfortunately, the virtual voice lab has been a “work in progress” much longer than I had hoped it would be when I started it two years ago. In this tutorial, you will add a new router to your GNS3 topology. It will connect it to the HQ, BR1 and BR2 routers to simulate an Internet connection and the Public Switched Telephone Network (PSTN).

 

There is one caveat to this PSTN simulation… GNS3/Dynamips is not capable of simulating traditional analog or digital circuits. We will be simulating an Internet Telephony Service provider (ITSP). ITSPs have become increasingly popular in the past ~5 years. Basically, the PSTN router will route incoming calls to the branch routers and received outgoing calls from the branch routers over a SIP or H323 trunk.
(more…)


As network engineers, many of us spend lots of time on the road. On nights not spent working on the install, a quiet hotel room can be a great place to study. In a previous post, you learned how to configure your Cisco router for dynamic DNS. This post will show you how to configure remote access vpn on a Cisco router to access your home lab remotely.
(more…)

This short post demonstrates using ‘ip sla’ and  freedns.afraid.org for dynamic dns.

 

(more…)


The company I work for has been implementing thin client technologies based on Citrix and Microsoft Terminal Services for a long time.  Today, VMWare’s Virtual Desktop Infrastructure (VDI) is starting to be the hot item.  This post addresses the network concerns presented by thin client technologies.  My first experience with this issue was presented by a small branch employee playing ‘Wheel of Fortune’ online.  The network died every time it was her turn to spin the wheel.

(more…)


Next Page »