Home computers and portables

• 1. Virus protection and firewalls
• 2. Computer clock synchronization
  • 2.1. Microsoft Windows
  • 2.2. Unix
• 3. Long delays when establishing a connection
• 4. Wi-Fi
• 5. How to choose a staff laptop

1. Virus protection and firewalls

As a student, you don't need to concern yourself with virus protection or firewalls when you use our computer systems. However, if you use a computer at home you should install both of those to avoid unexpected bills and strangers planting spyware on your computer.

As an employee, you need to obtain a decent firewall and virus protection for not only your home computer, but also for any portables you use at your office or elsewhere.

See information provided by University IT Support about virus protection and firewalls (only in Swedish).

2. Computer clock synchronization

Computers connected to any network may take advantage of the NTP protocol to synchronize their clocks.

2.1. Microsoft Windows

All Windows computers connected to Active Directory will automatically receive correct time from the department NTP server. If your computer isn't connected to Active Directory you should configure it manually. Go to Settings -> Control Panel -> Date/Time and select the third tab. Enter ntp1.it.uu.se as your NTP server.

2.2. Unix

Select ntp1.it.uu.se as your NTP server.

3. Long delays when establishing a connection

If you find that it takes quite some time for you to obtain a login prompt when connecting to a department server from an external network, one explanation may be that IDENT queries are being blocked. Some department servers respond to connection requests (for logging in or for file transfer) by querying the client about the user's identity, in case the connection has to be traced later.

If the client host doesn't run an IDENT server, the IDENT query will normally be rejected immediately, without noticeable delay. However, if the query is silently filtered away by a firewall, the department server will retry a couple of times before giving up. These retries may take several seconds.

The solution to this problem is to configure your firewall to let through traffic to TCP port 113 (IDENT). See also sp2 and ssh.

4. Wi-Fi

Uppsala university offers Wi-Fi in a number of locations, including Polacksbacken. There are two networks: UpUnet-s and Eduroam. All students and employees at Uppsala university can use the networks. Eduroam can also be used at other higher educational institutions in Sweden and Europe.
To access UpUnet-s the Password A is used and to access Eduroam Password B is used.
Here are some information about connecting to Eduroam.

5. How to choose a staff laptop

• A laptop must be purchased with 3-year service contract
• Some vendors have good/bad reputation within the department (long service delay etc):
  • Good references (2007): hp, siemens, lenovo (2011) Dell
    • (2008): pre-installed windows on lenovo systems do not work properly
  • Poor references (2007): acer
• Look at the following aspects:
  • 3 kg is remarkably heavy as conference baggage. The AC-adapter for a heavy computer is also heavier than for lightweight computers.
  • 2kg is considered a light weight computer.Will likely not be possible to combine with massive computing power. Generally flawless for presentations and preparations.
  • 17" screen is big and bulky. Useful if you use the laptop frequently, but then again you should strongly (!) consider a docking station (separate screen etc)
  • If to be used for scientific computer, don't underestimate memory consumption and cpu performance. At least 8GB ram and a quad core cpu is needed.
  • As a rule of thumb, Laptops are less secure than desktop computers. Consider a desktop or use our servers if security is a major issue.
  • You must set the bios-password (hardware password). Somewhat cumbersome to use but makes the laptop useless in case of theft, which promotes thieves not to come back to us. There is now a trace function for laptops to buy as an option from Dell and HP. The supplier will also help You to fill in a theft report to the police.
  • Bios passwords can be set in the initial hardware menu that shows up (by pressing F2, F12 or similar, laptop dependent) before loading of any operating system starts.
  • Sometimes there are two bios passwords, one takes precedence over the other.
  • Sometimes, a checkbox marks thast the bios password is to be used also during startup (should be set)
  • (2011) Laptops decreases in price. We recommend You to have a dialogue with the systems support group to ensure that You buy the right laptop.