Performance of Wireless Connections

Information on the reliability and performance of wireless connections

Reviewed by Bil Hays 04/29/2014

We get a lot of questions regarding wireless performance.  Here are some things to remember.

Wireless networking is prone to interference

802.11 networking occurs in “junk” bands that can be used by anyone.  The microwave ovens in Sitterson operate in the same frequency ranges as the wireless networks, as do many phones and other radio based devices, and bluetooth devices. Any usage by other devices at the frequency used by a basestation or radio NIC is seen by the networking devices as interference, which can disrupt the connection.

802.11 Networks drop speeds at lower signal levels

The way 802.11 works, the weaker the signal the slower the connection.  So even if you have a 54 Mbps card, you might only be connecting at 1 Mbps.  The effect is pronounced in Sitterson due to the amount of metal in the walls and floors of the building.

Wireless networking is a shared medium

This means that you have to share the bandwidth that’s available with other users.  If, for example, you ask your class to install a fairly large application, and 30 people then all try to get it at the same time, things are going to go slowly if you’re not connected with a wire. Please do not use wireless for your primary connection in your office, or for functions that are not work related (eg. listening to music–using 100-200 Kbps on the wireless is using a lot of bandwidth.)

What about 802.11A?

That operates in the 5 Ghz range, and thus the data rate drop off is more rapid than that of G devices (in simple terms, to a 5 Ghz device everything in the world looks twice as big in comparison to a 2.4 Ghz device).

I can’t get a strong signal

Because of the nature of it’s construction, Sitterson does not lend itself to the propagation of radio signals.  Also, the quality and strength of the wireless NICs vary.  You should be able to get a decent signal in most of the public areas in Sitterson (where the wireless is really intended for use).  If you cannot get a good signal in any particular area, please ask us to set up a wired connection for your use.

I can’t get very good throughput

See Performance and Usage below.  ITS does not guarantee any particular bandwidth on the wireless network.

I’m connected to HHONORS, or some other network instead of UNC-SECURE, what’s up?

There are other wireless networks in the area, including rogue ad hoc access points (that is, windows machines with wireless left on in ad hoc mode).  Try to set your machine up to seek out the UNC-SECURE and to not connect to other SSIDs if this is a problem for you.