1999 Cabletron Systems

Wireless Networking RoamAbout Security, FCC Regulations, and Safety inherent security Wired Equivalent Privacy (WEP) FCC guidelines

1999 Cabletron Systems Wireless Networking RoamAbout Network Name and Association In this scenario, the only station in this cell that will be able to associate with the AccessPoint is station B AccessPoint Station A Network Name: sales Station B Network Name: admin

1999 Cabletron Systems Wireless Networking RoamAbout Authentication Stations must first authenticate with an AccessPoint before they can associate with it IEEE defines: –Open System Authentication –Shared Key Authentication (based on Wired Equivalent Privacy (WEP))

1999 Cabletron Systems Wireless Networking RoamAbout Open System Authentication In open system mode, station A makes an open system Authentication request to the associated AccessPoint Authentication request (Open System Authentication) Station A AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout AccessPoint responds and authentication is complete –Note: This mode of operation, although secure for the most part, is not as secure as operating with Wired Equivalent Privacy (WEP) installed Open System Authentication Authentication response (Open System Authentication) Station A AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout Encryption RoamAbout offers encryption to meet security concerns –Base 40 bit encryption –Optional 128 bit encryption –Encryption based on RC4 (1988 RSA algorithm) –Used by Netscape, Microsoft, Oracle and Lotus (80 million users) –The encryption is used in a shared key format which is used to: Encrypt a challenge text string by the end station and To decrypt the challenge text string response by the AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout Station makes a shared key authentication request Shared Key Authentication (WEP) Authentication Request Station A AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout Shared Key Authentication (WEP) AccessPoint replies with a “challenge” text string AccessPoint Challenge Text String Station A

1999 Cabletron Systems Wireless Networking RoamAbout Shared Key Authentication (WEP) The station encrypts the challenge text string with the shared key and responds to the AccessPoint with the Encrypted challenge text string Encrypted challenge text response Station A AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout The AccessPoint decrypts the encrypted challenge text and makes a decision to authenticate the station based on the results –Positive results in association –negative results in no association Shared Key Authentication (WEP) Positive or Negative response Station A AccessPoint

1999 Cabletron Systems Wireless Networking RoamAbout FCC Regulations Licensing –The requirements are such that as long as the manufacturer adheres to the regulations, a site license is NOT required by the end user Power requirements –USA 1 Watt from any omni-directional radio antenna 4 watts from any amplified antennas –Europe 100mWats from any source

1999 Cabletron Systems Wireless Networking RoamAbout FCC Channel Distribution MHz 2484 MHz ISM Band Channel number Top of channel Center frequency Bottom of channel

1999 Cabletron Systems Wireless Networking RoamAbout ETSI (Europe) Channel Distribution MHz 2484 MHz ISM Band Channel number Top of channel Center frequency Bottom of channel

1999 Cabletron Systems Wireless Networking RoamAbout Channel Distribution Worldwide Channel IDETSIFCCFranceJapan Cabletron AccessPoint Default channels