Wireless Networking
All-in-one version
(Regular [individual slides] version)
Overview
What is this wireless stuff?
The good: untethered, visitors, meetings...
The bad: management overhead, RFI
The ugly: SECURITY RISKS!
The Future: faster, more secure
What is it
Basically, ethernet via radio waves.
Several standards:
802.11b: 2.4GHz, up to 11 Mbits/second, range >100 meters
802.11a: 5.0GHz, up to 54 MBits/second, range ~20 meters
Low cost: <$150 for a hub, <$80 for a PCMCIA card
Very
popular; becoming pervasive
Includes encryption (
BUT...
more on this later)
The Good
VERY convenient for laptops (like this one!), presentations (ditto)
Available at conferences (no more "bull pen" terminal/pc rooms)
Cost competitive in places (wiring awkward, expensive, e.g. homes)
Works basically like most other networking
Traffic is encrypted (
BUT...
see "the Ugly")
The Bad
Management issues: need keys (or else run "in the clear" naked!)
RFI:
quote from a NRAO Scientist:
"
There's something implicitly immoral about NRAO using this stuff
"
Banned in GB (and likely at the VLA)
Problematic for the CDL (shielded rooms, new building, $$$)
Interference from 2.4GHz cordless phones, microwave ovens, etc.
See "The Ugly..."
The Ugly
SECURITY: WEP encryption now "trivial" to crack
Software to do this is widely available
Passive, watch for couple of hours (hard to detect such snooping)
Problem NOT encryption (RC4), but the implementation (STUPID!!!)
"War Driving" laptop crackers a huge problem for .COM, .GOV (.MIL?)
Fix to problem coming, but can't easily retrofit to hardware
For now: use SSH, SSL (https), VPNs to encrypt sensitive traffic
The Future...
CV, AOC have testbed systems
Policy
in the works
We'll require your "MAC" address before you can connect
We'll rotate the SSID network identifier and require a WEP key
We'll
strongly
encourage users to encrypt (SSH, SSL, VPN [coming])
We'll keep these darn things away from our scopes and receivers!
Pat Murphy