电信专业英英词典S-2

（单词翻译:单击）

　　Simple Network Management Protocol¹ (SNMP)

　　SNMP is the application protocol offering network management service in the Internet suite² of protocols³. A structure for formatting⁴ messages and transmitting information between reporting devices (agents) and data collection programs. Developed jointly⁵ by the Department of Defense⁶, industry and the academic community as part of the TCP/IP protocol suite; ratified⁷ as an Internet standard in Request for (Comment (RFC) 1098.

　　Simplex

　　Simplex is a transmission path capable of transmitting signals in only one direction.

　　Single Mode Optical Fiber⁸(s)

　　Single mode optical fibers⁹ have sufficiently¹⁰ small core diameters in relation to the wavelength¹¹ (frequency) of operation that electromagnetic (light) wave is constrained¹² to travel in only one transverse path from transmitter to receiver. This requires the utmost in angular alignment¹³ of light emitting devices at points where light enters the fiber and results in higher transmitter/termination costs than multimode fiber systems. See multimode optical fiber(s).

　　SMDR

　　station message detail record

　　SMDS

　　switched multimegabit data system

　　SMT

　　station management technology

　　SNA

　　Systems Network Architecture

　　SNI

　　subscriber¹⁴ network interface¹⁵

　　SNMP

　　Simple network management protocol. See Simple Network Management Protocol (SNMP).

　　SO

　　Service Order

　　SOC

　　Service Order Code

　　SONET

　　synchronous¹⁶ optical network

　　Space Division

　　Space division is a switch that implements¹⁷ the switch matrix using a physical, electrical, spatial¹⁸ link. Where older space division switches used electro-mechanical mechanisms¹⁹ with metallic²⁰ contacts, modern space-division switches are implemented²¹ electronically using integrated circuits. (Usually denoted by "S" in combined time and space division switches).

　　Special Services

　　Special services are any of a variety of LEC and IXC switched, non-switched, or special rate services that are either separate from public telephone service or contribute to certain aspects of public telephone service. Examples include PBX tie trunks, foreign exchange (FX) and private line services. These services are important to business telecommunication²² planners/users.