Wireless network at FIT campus is a part of WiFi network of BUT.
This network is available to all students and faculty members
who are assigned access password for BUT Information System (which is not
Conditions of Use
- WiFi card conforming to IEEE 802.11b/g standard (11/54 Mb/s), standardn settings, short preambles, no special extensions, such as 22 Mb/s, 4X, 108 Mb/s, 8X, g-only, Turbo, etc.
- Configure SSID=VUTBRNO (in Windows XP enable service Wireless Zero Configuration and search for available networks).
- None of WEP, TKIP, MIC, and 802.1x is used for now.
- Enable automatic configuration (DHCP) for WiFi card to obtain IP address, DNS servers, gateways etc. automatically.
Fixed IP address setting is considered a serious offence of
Operating rules of computer network at BUT.
- Launch any Web browser for any WWW page. It will be redirected to authentication page of BUT WiFi network (if this fails check if you were assigned IP address
in range 147.229.94.x - 220.127.116.11 and if you have no proxy cache server configured).
- Authenticate yourself using "BUT login" ie. password for IS BUT
(it is used for dormitory registration and is not identical to IS FIT).
- Without authentication you can access IS FIT only over encrypted connection (http over SSL/TLS).
- After successful authentication you obtain free access to Internet but the gateway does not permit any incomming connections. As a result it is not possible to operate any servers over WiFi and for ftp access passive mode is required.
- WiFi network is not considered as part of address space of FIT network.
Therefore all services of FIT network may not be available.
- WiFi network by design is not secured against wiretapping and all traffic may be easilly monitored. Be sure not to supply any sensitive information (passwords) over open (unencrypted) connections, e.g. FTP, telnet, http, impa4, pop3, etc.
The network was started up on Octber 16th 2003, for operational access points see map of campus.
- How Can I Obtain BUT password?
- See Computer Centre->Guieds, manuals->Student Accounts
- What does Mean 802.11a,b,g Names?
- These names indicate IEEE 802.11 standards for wireless local networks.
The oldest IEEE 802.11b defines trnasmition in 2.4GHz range using 1-11 Mb/s.
IEEE 802.11a defines speed 6-54Mb/s in 5GHz range and IEEE 802.11g in the same range as 802.11b with speed 1-54Mb/s (different signal modulation in the same frequency range).
Devices in 2.4GHz range are permited by General Licence and do not require
- Why there is not 802.11g everywhere?
- There are several reasons: lower AP power (about 20-30 mW), thus lower coverage, problems with initial firmware revisions and unavailability of reliable APs, problems with compatibility of WiFi cards and APs (although AP 802.11g permits 801.11b cards some older cadrs cannot establish connection with 802.11g AP).
During the year 2004 original APs 802.11b D-Link DWL-900 will be replaced by
new APs 802.11g HP-420.
- Why 802.11g throughput is 10Mb/s only (instead of 54Mb/s)?
- 54 Mb/s througput of 820.11g network is theoretical signaling rate.
This speed cannot be achieved - unlike metalic networks where 100Mb/s may
be really used.
Real transfer rate of 802.11g is 20 Mb/s on very special conditions -
distance from AP just few meters, single client in the network, no 802.11b
card in the network.
If there is even a single 802.11b card in the network througput of the network
is significantly restricted because of RTS/CTS protocol which has to switch to
802.11b slow signaling rate. The network speed in such circumstances
often drops down to 10Mb/s.
More details may be found in
When Is 54 Not Equal to 54?.
The speed depends on chips set used in both cards and APs and on firmware and drivers.
- I have no WiFi card, which one to buy?
- Any CardBus (PCMCIA) supporting 802.11b/g will do (in the future b/g/h). The card should support WPA (WiFi Protected Access, subset of future 802.11i).
It's reasonable to consult release notes, you should find term like 802.1x, TKIP, MIC and in best case AES.
WPA is not used now but may be required in the future.
It's not recommended to buy older cards. Although the price may be nice
you may enacounter serious problems.
For any card you should obtain the latest drivers and firmware from the manufacturer's web site.
- Why is WiFi so slow (ping roundtrip is 100 ms)?
- There are probably too many clients associated to an AP transferring large volume of data.
- What about 802.11a?
- Operation of devices according IEEE 802.11a (54 Mb/s in 5 GHz range)
is not allowed in EU. The problem is solved by IEEE 802.11h (Spectrum Managed 802.11a) accepted in December 2003.
General Licence is under preparation.
802.11h is in fact 802.11a with addition of TPC (Transmission Power Control)
and DFS (Dynamic Frequency Selection). It seems to be a matter of firmware, other features are compliant with 802.11a. There are no 802.11h cards available now.
- WiFi is fine but what about power outlet
- Power outlets will be provided on all places where power cables are available. This cannot be done in new lecture halls (E104,105,112) where are no power cables in auditorium.
Investment division is notified about this problem so hopefully any new lecture hall, laboratories and classrooms will be equipped with power outlets during reconstruction of Božetěchova campus.