Complete Communications Engineering

Low speed digital carrier systems include both the ever popular T1 and E1 circuits which are used for basic multiplexing of analog voice calls. Each analog voice call is carrier as an 8-bit digitized companded sample in a timeslot. T1 has 24 useable voice channels and E1 has 30 voice channels.

VOCAL T1/E1 Trunk Management Software implements a comprehensive set of services for a T1/E1 system. Included are the configuration interface, alarm management, configuration management, maintenance management (loopback, performance) and signaling management.

Extensive driver support for various T1 and E1 framers from Dallas/Maxim.

The Alarm Management Services (AMS) use the framer hardware alarm detectors for the Far End Alarm (Yellow or RAI), Alarm Indication Signal (AIS), Loss of Signal (LOS) and Out of Framing (OOF) and applies configurable timers to declare/terminate the local alarm conditions (RAI or AIS). T1 alarm capabilities meet the standards as per T1.231; E1 per G.731, I.431 and ETSI 300233.

The Configuration Management Services (CMS) monitors the configuration and clock status across all interconnected T1/E1 devices. Its primary purpose is to ensure the use suitable recovered receive clocks according to a priority and/or default clocking policy.

The optional Maintenance Management Services (MMS) implements loopbacks and performance monitoring with the exchange of performance reports. Facility Data Link (FDL) messaging issued in ESF configurations to implement ANSI T1.403 and AT&T TR54016 requirements.

The Signaling Management Services (SMS) implements the various robbed bit signaling (RBS) and channel associated signaling (CAS) modes for T1 and E1 framer configurations respectively. The SMS processes the signaling bits according to the selected signaling mode on a channel by channel basis. For ease of configuration, channel groups are which have common control parameters and timers.

T1 RBS Signaling Modes

E1 CAS Signaling Modes

Tone Signaling Support

Common driver features provide a robust and comprehensive environment for the development of T1/E1 communications equipment.

Common Features