Virus Information

This page contains information for GSD Computer users about basic anti-virus measures provided on the GSD network, and measures that individuals must take to protect their own and others' computers.

In this document

About Viruses
What we do
- Anti-Virus measures on the network
- If your computer is QUARANTINED
What you should do

About Viruses

Most "viruses" are computer programs designed to do malicious things, including trying to propagate themselves to other computers, send SPAM or PHISHING email, etc. You can unwittingly install such programs quite easily, often by clicking on an attachment in an infected email message, downloading software from some untrustworthy website, installing software from an unreliable source (including 'cracked', 'free' or 'bootleg' software), etc.
Often, vulnerabilities in Operatng Systems or other software are exploited to infect your computer, which is why is it is critical to apply the manufacturer's software updates, or 'patches' in a timely fashion, as well as keep anti-virus and anti-spyware software current.

What we do

Anti-Virus measures on the network

All computers connected to the GSD network must be virus-free and protected from common viruses, worms, infections and exploits ("malware").

The Computer Resources Group (CRG) maintains all school-owned computers in a safe, clean and functioning state, and monitors the network for virus attacks; individual students' computers are their owners' responsibility.

Email Filtering

The GSD E-Mail system is automatically scanned for a number of well-known viruses, which are eliminated or rendered harmless. However, some viruses may get through.

Shared Network Drives

The various shared network drives on the GSD system are NOT protected from viruses in the files stored there.

Network Monitoring

The GSD uses a network control system called 'PacketFence', which automatically detects the most common kinds of malware, and automatically removes ('quarantines') infected computers from the network until the problem is repaired. Quarantined computers will be unable to connect to the network until the malware has been removed and helpdesk has been informed. Packetfence is a piece of network management software developed at Harvard and used at the GSD. It works on the back end of the network to monitor for virus activity and to control unauthorized access to the network. As a user of the GSD's network you should barely notice packetfence unless a virus or worm is detected on your computer (other than an initial registration with the system to get access to the network.)

If your computer is QUARANTINED

This means that one of several specific signatures of malicious activity has been detected, originating from your computer. If you launch a web browser, you will see a page identifying the cause of the quarantine and the recommended repair procedure. Infected computers may require a complete reinstall. Please make sure you keep backups!

What happens if you are "quarantined"

Packetfence monitors network traffic and if it detects virus-like bahavior eminating from your computer, it will "quarantine" your computer. If you open a Web Browser and try to access any page, packetfence will prevent you from reaching it, and instead will force you to its quarantine page. At this point you very likely have a virus, and you need to deal with it. On the quarantine page you are allowed to re-enable your network access for a few hours with the sole purpose of fixing your virus problem. Make an attempt to solve the virus problem on your own, by running a full virus scan and consulting anti-virus websites for any further steps you can take to alleviate the problem. Once you have purged your machine of virus, you may re-enable network access.

If you are quarantined a second time, you should bring your machine up to the helpdesk for assistance, but it is very likely that you will need to reinstall the operating system.

What you should do

Anti-virus programs alone will not completely protect your computer. You must also rigorously apply all security patches for your operating system, and for all programs that connect to the internet, such as email clients, web browsers, and instant messaging clients.

No externally connected network is 100% safe, no matter how much time or money is spent. The final power lies with you. By following our guidelines and being vigilant, you can keep your personal risk of malware low.

Personal Anti-Virus protection

Each computer on the GSD network is required to be protected against the common forms of malicious viruses, by some regularly updated antivirus program. The choice and deployment of these is left to individual users. There are a number of free antivirus clients available that offer sufficient protection.

Note that all Anti-Virus software must be regularly updated, to account for new and evolving viruses. Simply installing the software is not sufficient. A weekly update schedule at a minimum is recommended; daily updates are often required!

How to prevent it from happening again

Maintain anti-virus software constantly up-to-date
Maintain Microsoft Windows patches constantly up-to-date
Run "spyware detection software", such as ’Ad-Aware’ or 'Microsoft AntiSpyware' regularly
Use caution when surfing the web & reading attachments in email
Don’t install ‘cracked’ software !