Monday, July 23, 2001		Bits & Bytes

Walled garden: On the Internet, a walled garden refers to a browsing environment that controls the information and Web sites, the user is able to access. This is a popular method used by ISPs in order to keep the user navigating only specific areas of the Web, whether for the purpose of shielding users from information — such as restricting children's access to pornography — or directing users to paid content that the ISP supports. America Online is a good example of an ISP that places users in a walled garden. Schools are increasingly using the walled garden approach in creating browsing environments in their networks.

BER: Short for bit error rate. In a digital transmission, BER is the percentage of bits with errors divided by the total number of bits that have been transmitted, received or processed over a given time period. The rate is typically expressed as 10 to the negative power. For example, four erroneous bits out of 100,000 bits transmitted would be expressed as 4 x 10-5, or the expression 3 x 10-6 would indicate that three bits were in error out of 1,000,000 transmitted. BER is the digital equivalent to signal-to-noise ratio in an analog system.