Albert Einstein explained it best:

1
What is wireless

• Albert Einstein explained it best
• "You see, wire telegraph is a kind of a very,
  very long cat. You pull his tail in New York and
  his head is meowing in Los Angeles. Do you
  understand this? And radio operates exactly the
  same way you send signals here, they receive
  them there....

2
What is wireless

• ...The only difference is that there is no cat."

3
Wireless LAN 802.11

• What is it
• Versions and Standards
• How we deploy it
• How we manage it
• How we secure it
• How we improve it

4
What is it

• IEEE standard for wireless ethernet
• Introduced in 1997
• Replacement for physical cabling to each host
• Has seen dramatic increase in popularity over the
  past few years.

5
Versions and Standards

• Original 802.11 offered 1 and 2 Mbps speeds in
  the 2.4GHz band
• 802.11a added a 54Mbps speed in the 5GHz band
• 802.11b added 11Mbps speed in the 2.4GHz band
• This extension is now synonymous with 802.11
• 802.11g added 22Mbps and 54Mbps speeds in the
  2.4GHz band
• 802.11i improves the security and encryption
• 802.11n will add much higher speeds of
  potentially several hundred Mbps

6
How do we deploy it

• Locating, configuring and installing 'access
  points' or AP's.
• AP's connect the wireless clients to the wired
  network
• Currently we employ about 75 AP's across all
  campuses.
• Originally only provided in conference rooms
• Now provided in (almost) all office space

7
Locating and Surveying

• Optimal locations determined via in the field
  testing
• Testing is done with Cisco client software as
  well as custom survey software
• Survey software eventually produces web pages
  showing coverage

8
How do we manage it

• All access points are kept in a database
• NETS manages DHCP server for wireless network
• AP's are given static addresses while clients get
  dynamic ones
• AP's download their configuration at boot time
  from the DHCP server
• This gives them consistent default settings along
  with individual names.

9
How do we secure it

• Wireless is inherently less secure than cables
• Easier to both gain access to wireless and to
  watch what other people are doing
• Original 802.11 spec included encryption Wired
  Equivalent Privacy or WEP
• WEP was difficult to use and contained several
  flaws which were later discovered rendering it
  almost useless
• We now rely on a security gateway and VPN

10
Security Gateway

• Operated by Rich Johnson and the security group
• Allows all VPN traffic. This is the preferred
  method for staff to secure their wireless traffic
• Also allows guest logins. These provide control
  over who uses the network, but does not provide
  the users with any privacy
• http//guest.wireless.ucar.edu to set up guest
  accounts
• http//wireless.ucar.edu to log in to guest
  accounts

11
How do we improve it?

• Re-deployment starting RSN
• Coverage is spotty due to two-stage deployment.
• Too much in some areas
• Too little in others
• New AP's provide 802.11g and higher speeds

12
How do we improve it?

• New AP's allow multiple networks at once
• Provide new per-campus staff-only networks and
  maintain legacy network at the same time
• New security via 802.11i AKA 'WPA2' may allow
  staff to 'log in' to wireless securely and skip
  the VPN

13
Troubleshooting
14
Guest Logins