NetAdmin newsletter issue #24

Dear Network Administrators,

This CPTTM NetAdmin newsletter is to bring useful news to you, Network Administrators in Macau, for references without obligations, so that you can do your jobs easier and better! Hope you like it. if you'd like to unsubscribe or recommend your friends to subscribe, just email me at alan@cpttm.org.mo. Old issues are available here. Also printable version for this newsletter.

Topics in this issue:

Open-source real time anti-virus, anti-spyware and anti-trojan software

You may have learnt about or been using Clamwin, an open-source anti-virus to protect you computer. The shortcoming of Clamwin is that it does not provide real time protection.

Now, there is another open-source software called : Winpooch. It provides real time scaning on the running process activities to prevent spywares and trojans from installing. When working in conjuction with Clamwin, it can also provides real time virus scanning.

Try them out to protect your computer with no cost.

-- by Alan Au

Case study - How Cyberlab solves a wireless LAN connectivity problem

We have deployed a 54M Wireless LAN in one of Cyberlab classrooms, with one normal home wireless access point and 30 USB wirelss adapters. There have been some reports from the students that they could not connect to the wireless network. Usually, this happens to about 10 or so computers and it is very difficult to get them connect back.

We have tried to swtich to other wireless channels, upgrade the firmware of the wireless access point. Apparently, it became better just afterwards but actually the problem wasn't fixed. Until recently, we have got one more wireless access point and deployed it to that classroom. We assign half of the computers to each access point. Now, the problem is really fixed, although occasionally, one or two students might report connectivity problem but it can be easily fixed.

I have tried to find out the maximum or recommended no. of clients that our current AP can support but there is no such information from the vendor website. While I can find some figures for Cisco Aironet AP and Aruba AP (max and recommened). For Cisco Aironet AP, max = 2048, recommeded = 24. For Aruba AP, max = 255, reoommeded = 24. So, before you deploy Wireless LAN in the future, you should find out the recommended no. of clients first.

--by Alan Au

Design flaw in wireless VoIP handsets endangers the enterprise

802.1x/EAP enterprise-grade authentication is the most secure and robust secuirty mechanism in user authentication for wired and wireless network. Many wirelss VoIP phone handsets implement 802.1x/EAP. But, according to an article from ZDNet, it is found that a few implementations of them posses a security risk.

It is because that these implementations have simplified the 802.1x/EAP authentication process - Bypassing the Authentication server certificate verification process at the client side. This speeds up the authentication process but introduces a security risk of being easily for the hackers to reveal the user' s passwords.

To read the details and the countermeasure, please read this ZDNet article.

Fully automated software deployment solution for Windows

Have you encountered the need to deploy same software or files to a lot of PCs in the same time with the same configuration? The stupidest way was to do it one by one. WPKG It would be a waste of your resources. In general, system administrator would add all PCs to Active Directory and complete by windows deployment tool and Group Policy. But when your software is not in msi. What would you do?

WPKG enables you to implement an automated software deployment solution without restriction. It can install MSI, InstallShield, PackagefortheWeb, Inno Setup, Nullsoft and other software installers.

In fact, we are using WPKG in some classrooms at Cyber Lab. It helps to reduce a large amount of manpower.

For more detial, please see WPKG webpage.

--by Eric Chan

PostgreSQL 8.3 release

PostgreSQL is a powerful, open source relational database system. It runs on all major operating systems, including Linux, UNIX (AIX, BSD, HP-UX, SGI IRIX, Mac OS X, Solaris, Tru64), and Windows. It is fully ACID compliant, has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages).

Last month PostgreSQL released its 8.3 version. As mentioned on news.com, PostgreSQL has improved performance from 5 percent to 30 percent. There were a lot of new functionalities and performance enhancements. The following list would show some major features:

Full text search is integrated into the core database system
Support for the SQL/XML standard, including new operators and an XML data type
Updatable cursors
Automatically re-plan cached queries when table definitions change or statistics are updated
Numerous improvements in logging and statistics collection
Support Security Service Provider Interface (SSPI) for authentication on Windows

For more details, please see Posgre Webpage and this article.