The Wireless
ethernet provides internet access to mobile computers without connection
cables. Instead, it uses radio communication between the computer
and TC Access Points.
There are several
versions of wireless ethernet in use today. TC's wireless ethernet
is based on the IEEE 802.11b "high rate" standard, therefore only
devices that use this protocol will work on the TC campus. An upgrade
to IEEE 802.11g (which is compatible with the 802.1b standard) is
planned soon.
Why are we doing this?
The key advantage
of wireless Ethernet is flexibility. Your PC does not have to be
chained to a network jack. Network access can be found in places
previously not available such as the TC cafeteria and Everett Lounge.
Access to the network can be provided for less cost than with wired
networks.
However, there are also some disadvantages which make this service
complementary to our wired networks. Our wired networks will continue
to provide higher performance and better security.
How fast is it?
The IEEE 802.11b
standard has a nominal speed of 11 megabits per second (Mbps). However,
depending on signal quality and how many other people are using the
wireless ethernet through a particular Access Point, usable speed
will be much less (on the order of 4 or 5 Mbps, which is still substantially
faster than most dialup, cable and DSL modems). CIS plans to upgrade
to the IEEE 802.11 g standard in the near future, which will allow
for a 54 Mbps connection. For more information on the g standard,
click on the following link: http://standards.ieee.org/announcements/80211gfinal.html
Is it secure?
No, Wireless
ethernet is insecure by default. Any user on the Wireless Local
Area Network (LAN) can spy on unencrypted traffic from other wireless
users. Wired connections on TC's campus are generally more secure
when communicating with other TC servers, however when connecting
to sites off-campus, only encrypted connections are secure. Users
are advised to use Kerberos authentication, or SSL to connect to
web pages and mail hosts, and SSH instead of telnet whenever possible.
You may see literature saying that the 802.11b standard includes
provisions for optional 40- or 128-bit link-level encryption over
the air, however, current implementations require the encryption
key to be shared by all users of the wireless LAN, effectively eliminating
the usefulness of this security feature in an open campus environment.
Is it safe?
All devices
on the market are approved by the FCC, which has a good public document
on RF Safety .
What kind of wireless card does TC support
and recommend?
The TC wireless
network is currently running the 802.11 B protocol. Wi-Fi compatible
wireless cards of Type B or Type G both will work on the TC wireless
network; (note: the 802.11 G protocol is downwardly-compatible with
802.11 B). When the wireless network is upgraded to 802.11 G, wireless
cards of Type B and Type G will both continue to work.
If a wireless
access point is running the faster G protocol, if even one wireless
device of Type B is connected to that access point, then all wireless
devices will run at the slower 802.11 B speed. For that reason,
we strongly recommend that new purchases of wireless cards be of
Type G cards.
Will the wireless card conflict with my
ethernet card/modem?
Both devices
should function properly if you use one at a time. If you encounter
problems, first make sure you have installed both cards according
to the installation instructions that came with the modem/ethernet
card and the wireless card, then contact the manufacturers for support.
Do I need to register my wireless card
with hostmaster?
Yes, please
click here and submit the registration
form:
Can I request a static IP/hostname?
No, the Wireless
ethernet only works with dynamically assigned IP addresses.
Troubleshooting?
First refer
to the Troubleshooting section of the Installation
Instructions . If additional assistance is needed, students
please call Academic Computing at x3302; faculty and staff please
call the TC Helpdesk at x3300.
Using Wireless Ethernet on Campus
Where on campus can I connect with Wireless?
See our Coverage
Map , and feel free to print this out.
What happens if I move around from zone
to zone?
Your Wireless
card will always try to connect to the stronger signal. As soon
as another Access Point has a stronger signal your connection will
switch, but continue uninterupted service.
What happens if I leave and then re-enter
the coverage area?
Leaving the
coverage area will destroy your connection. Upon re-entering, in
unlikely circumstances, you may need to reboot your computer, however
most of the time, you will be able to continue where you left off.
Will Appletalk/Microsoft File-Sharing
work?
The CIS department
only supports TCP/IP on the Wireless ethernet. This does not include
AppleTalk, Microsoft File-Sharing, IPX/SPX, or NetBEUI.
What is the University policy on personal
wireless networking on campus?
With the rapidly
growing popularity of low cost wireless Ethernet come some obstacles
to the proper operation and performance of this technology. Due to
the shared nature of the rather small 2.4 GHz ISM band, we all must
be aware of the potential negative effects of interfering wireless
devices. Examples of wireless devices which can interfere, especially
with the 2.4 GHz ISM band which is used for Wireless Ethernet include:
2.4 GHz spread spectrum cordless phones
2.4 GHz consumer short distance wireless video links
Wireless Ethernet Access Points including the Apple Airport
Base Station and the Macintosh computer operating as a software
base station.
Any computer operating in IEEE 802.11b Ad-Hoc mode
Some scientific equipment.
Devices such as these should not be operated in Teachers College buildings
without prior frequency coordination with CIS due to the interference
they can cause with the campus wireless network infrastructure. Your
cooperation is appreciated and will ensure an efficient and well-structured
wireless network.
Can I print?
No, there are
currently no printers setup in the wireless access areas.
