e PHY Device regional radiocommunication conference route switch processor RealTime relative time error real-time transport protocol Radio Unit (5G radio access network) stratum 2 (ANSI T1.101) Services and System Aspects source address standalone System Architecture Evolution search and rescue (service) Standards Association Standards Board standalone synchronization equipment SAToP structure-agnostic TDM over packet service-based architecture space-based augmentation system SC-FDMA single carrier frequency-division multiple access Software Community (O-RAN) SCADA supervisory control and data acquisition SD-WAN Software-Defined Wide Area Network System of Differential Correction and Monitoring synchronous digital hierarchy (optical transport technology) Software-Defined Network standards development organization SDH equipment clock synchronous equipment clock secondary eNodeB synchronous equipment timing source signal fail single frequency network small form-factor pluggable-plus (transceiver) small form-factor pluggable (transceiver) study group Study Group 15 (of the ITU-T) serving gateway International System of Units subscriber identity module service level agreement synchronization metadata SubMiniature version A (connector) SubMiniature version B (connector) SONET minimum clock SMPTE Society of Motion Picture and Television Engineers Simple Network Management Protocol signal-to-noise ratio Simple Network Time Protocol SNTPv4 Simple Network Time Protocol version 4 SONET synchronous optical network (optical transport technology) service provider (for telecommunications services) segment routing Stream Reservation Protocol synchronization status message standards setting organization secondary synchronization signal SSU-A primary level synchronization supply unit (SDH) SSU-B secondary level synchronization supply unit (SDH) SSU-L synchronization supply unit-local (SDH) SSU-T synchronization supply unit-transit (SDH) synchronization supply unit (SDH) stratum 3E (ANSIT1.101) set-top box STM-N synchronous transp