DSSS
Direct-Sequence Spread Spectrum. DSSS is a transmission technology used in WLAN transmissions where a data signal at the sending station is combined with a higher data rate bit sequence, or chipping code, that divides the user data according to a spreading ratio. The chipping code is a redundant bit pattern for each bit that is transmitted, which increases the signal's resistance to interference. If one or more bits in the pattern are damaged during transmission, the original data can be recovered due to the redundancy of the transmission.
Dynamic IP Address
An IP address that is temporarily leased to a host by a DHCP server. The opposite of Static IP Address.
E
ESS
An Extended Service Set (ESS) is a set of two or more BSSs that form a single subnetwork. See also BSS.
Ethernet
The most widely used LAN type, also known as IEEE 802.3. The most common Ethernet networks are 10Base-T, which provide transmission speeds up to 10 Mbps, usually over unshielded, twisted-pair wire terminated with RJ-45 connectors. Fast Ethernet (100Base-T) provides speeds up to 100 Mbps. “Base” means “baseband technology” and “T” means “twisted pair cable.”’
Each Ethernet port has a physical address called the MAC address. Also see MAC address.
Event
A message generated by a device to inform an operator or the network management system that something has occurred.
F
Firewall
A security software system on a router that enforces an access control policy between the Internet and the LAN for protection.
Firmware
Code written onto read-only memory (ROM) or programmable read-only memory (PROM). Once firmware has been written onto the ROM or PROM, it is retained even when the device is turned off. Firmware is upgradeable.