Thursday, August 25, 2005

Handling GUID's (UniqueIdentifiers) in DB2 using VB.NET

Continuing the saga of DB2, I am now trying to handle GUID's/UniqueIdentifiers from the Enterprise Library. First thing I had to get a handle on is that DB2 UDB has no datatype similar to a GUID. In Microsoft SQL they are represented as UniqueIdentifiers and used quite extensively. Oracle represents them as RAW(16). When I ran the conversion on my database using the IBM Migration Toolkit (MTK), the GUID's in my database were converted to CHARACTER(16) FOR BIT DATA. So basically, a container to hold 16 bytes worth of data. It takes 2 hexadecimal characters to represent 1 byte so 32 hexadecimal characters is 16 bytes or 128-bits.

Monday, August 22, 2005

IBM DB2 on Fedora Core 3 64-Bit

I have moved on to my next adventure in writing a native database interface. We have decided to add native DB2 support to our product offering. I was fairly excited when I first started out to install this but after 5 days, I am frustrated and dismayed at the lack of forethought or testing put into the product. I downloaded DB2 8.2 from IBM's web site and installed the 90-day trial for enterprise edition on my Sun Sunfire V20Z development server running Redhat Fedora Core 3, 64-bit edition. Now I bet there are alot of people who want to test DB2 under these types of conditions and from what I read, it just won't work.

Friday, August 12, 2005

Callvantage QoS

I finally got around to fixing the QoS problem with my Callvantage VoIP setup. After determining about 3 months ago that my Callvantage box was dropping packets and causing general outbound havok on my system, I decided to move it inside my network behind my trusty linux firewall/router/mailserver/gameserver box. The unfortunate side effect was that I lost the Quality of Service capabilities. This caused a serious delay in voice transmission and sometimes even stuttering while I was talking on the phone. I usually just accepted it until my friend got his new Actiontec router and it handled VoIP QoS automatically. Now if Actiontec can do it, I know my outdated Redhat 7.3 install should be able to.

Tuesday, August 2, 2005

Coaxial Run with Power CCTV Troubleshooting Guide

Written by Jim Shank 8/2/05


There should be two major troubleshooting points for CCTV, the camera’s themselves and the central terminating location (CTL) in which the video signal is captured and the power is supplied (if power is not supplied mid-run or directly at the camera location). Troubleshooting will be started at the CTL and then move to each individual camera. It helps to have a baseline camera that is working in order to capture normal readings for comparison. Remember that CCTV cabling should be as follows

UTP with Baluns
Fiber Optic

Run Length

< 250 ft.

250 – 3000 ft.

> 3000 ft.


Tools Needed

  • Digital Volt Meter (DVM)

  • Electrical Tape

Optional Tools

  • BNC or F-type connector and small piece of coax

  • 9V battery