Installation and Administration Guide 501March 2000 GlossarySPRE codeA Special Prefix code that is used to initiate use of a PBX feature. In a RemoteOffice context, SPRE codes are used to toggle a remote site between online and offline modes use the paging feature switch an analog or ATA-equipped station from host-controlled mode tolocal-controlled mode so that local calls can be made register a Remote Office 9150 unit for a multi-user or dynamic portstationA telephone or fax machine located at a Remote Office 9150 site.stop bitIn asynchronous communications, a bit that indicates a byte has just beentransmitted. Every byte of data is preceded by a start bit and followed by a stopbit.subnet maskA subnet mask is the part of the IP address used to represent a subnetworkwithin a network. A typical IP address might be 192.210.34.144. Each part ofthis address is made up of eight bits. The subnet mask identifies to the MIG RLCor remote unit what portion of the IP address represents the network (andsubnetwork) and what portion represents the host.switchIn a telecommunications network, a switch is the hardware that receives phonecalls and provides connections to phonesets. The switch allows a connection tobe established as necessary and terminated when there is no longer a session tosupport it.In data networks, a switch is a device that filters and forwards packets betweenLAN segments. Switches operate at the data link layer (layer 2) of the OSIReference Model and, therefore, support any packet protocol. LANs that useswitches to join segments are called switched LANs or, in the case of Ethernetnetworks, switched Ethernet LANs.
