SG (Signal Ground)
A signal from DTE to DSU/CSU.
simplex current
One way transmission used by Telco to provide power to repeaters.
SLIP (Serial Line IP)
A TCP/IP protocol that allows IP packets to be transmitted over a serial link, such as a dial-up or private telephone line.
SMDS (Switched Multimegabit Data Service)
Afast-packet technology based on the connection-less data networking capability described in the IEEE 802.6 specification. The data format for SMDS is “cell oriented.” SMDS does not support voice.
SNMP (Simple Network Management Protocol)
A widely-used network monitoring and control protocol. Data is passed from SNMP agents (hardware and/or software processes reporting activity in each network device, hub, router, bridge, etc.) to the workstation console used to oversee the network. The agents return information contained in a MIB (Management Information Base), which is a structure that defines what is obtainable from the device and what can be controlled.
stop bit
The last transmitted element in each character, which permits the receiver to come to an idle condition before accepting another character.
subnet mask
The number of bits in an IP address used for the subnet address.
synchronous transmission
Data communications in which characters or bits are sent at a fixed rate and the transmitting and receiving devices are synchronized.
T
T1
A digital carrier facility used to transmit a DS-1 formatted digital signal at 1.544 Mbps. T-1 normally can handle 24 voice conversations, each one digitized at 64kbps. But, with more advanced digital voice encoding techniques, it can handle more voice channels. T-1 is a standard for digital transmission in North America. T-1 lines are used for connecting networks across remote distances.
T3
A digital carrier facility used to transmit a DS-3 formatted digital signal at 44.736 Mbps.
