1. Terry Gray Networks & Distributed Computing 19 March 2002
WIRELESS UPDATE
Terry Gray
Networks & Distributed Computing
19 March 2002

2. What’s New? 802.11a here sooner/cheaper than predicted
Climate of increasing liability concerns
More standards

3. 802.11a: Successor? Faster (54 vs. 11… really 27 vs 6)
Shorter distance (30m vs. 100m)
More power consumption
Available now at 2x price of b
Incompatible w/ b installed base
Probably need WAPs for both, or dual-mode WAPs

4. LAN Wireless Standards
IEEE GHz, 1-2Mbps, FHSS, DSSS
IEEE a 5Ghz, 54Mbps
IEEE b 2.4Ghz, 11Mbps DSSS (WiFi)
IEEE e QoS, etc
IEEE f Inter-AP protocol
IEEE g 2.4GHz, 20+Mbps
IEEE h “spectrum managed” a
IEEE i Security, incorporating 802.1x
IEEE j Convergence w/Hiperlan
In US, all use unlicensed “ISM” bands

5. Global 802.11 Issues WISPr (wide area) roaming
Comcast vs. community bandwidth sharing
Shutdowns due to security concerns
Shutdowns due to interference

6. Campus 802.11 Issues liability --”attractive nuisance” addressing
roaming
management
ad hoc installations
maturity: a e g h i
designing for both b and a
cost recovery for enterprise deployment

7. C&C Wireless Approach Dedicated per-building subnet
addresses, performance, fault isolation
Enterprise access points + auth server
Auth policy: perimeter control only
Assume insecure: use SSH/SSL/K5
Convenient user configuration
L2 roaming only

8. Conclusions: Same as Before
Wireless is very addictive.
It will be very popular.
It will be very problematic.
It will cost more than you expect.
In offices, it is not a replacement for wired.
The dust has not settled.