The Protocol-Specific Function (PSF) for Trillium Session Initiation Protocol (SIP) Fault-Tolerant/High-Availability (FT/HA) software enables SIP to execute in pure fault-tolerant (active/standby) and distributed fault-tolerant (N active * M standby) systems. PSF – SIP updates the standby copy with stable state changes from the active copy. In case of failure, the standby copy can assume operations with minimal disruption in the system. This ensure active call continuity despite equipment failure. The following diagram illustrates the high-level architecture for SIP FT/HA software.

Diagram Trillium SIP PSF

Trillium PSF-SIP enabled telecom equipment manufactures of VoIP and IMS network equipment to:

  • Accelerate time to market
  • Reduce initial and incremental development and support costs
  • Reduce project risk of internally developed SIP applications

Product deliverables consist of C source code software, Trillium XML test architecture (XTA), documentation, training, and warranty and technical support.

FEATURES + BENEFITS

  • Supports run-time state updates to keep the standby SIP synchronized with the active SIP Transient states are not updated at runtime.
  • Initializes the Out-Of-Service (OOS) resource sets with the data from the active resource sets.
  • Software fault detection capabilities including the heartbeat mechanism to detect communication loss with the peer SIP processors and the sequencing of update messages to detect synchronization loss.
  • Provides fault notifications through status indications.
  • Provides debugging aids, like trace and debug prints.
  • Updates the run-time state from the active resource set toward the standby resource sets.
  • Supports operator-initiated switchover allowing for the standby node to become active, and vice versa (controlled switchover), which prevents state loss.
  • Enables the SIP instance to handle the protocol events for other resource sets assigned to it during the controlled switchover of one resource set.
  • Supports the recovery procedures when an OOS copy is made Active during the forced switchover; capable of bringing the protocol database and system into a consistent state, after a forced switchover of the master critical resource set, to resume operation.
  • Stops sending state updates to the standby when it becomes OOS.
  • Supports warm start to make it standby from the OOS mode. PSF – SIP does not delay data traffic processing during the warmstart operation.
  • Capable of simultaneously performing operations, like warm start and peersync, on multiple resource sets.
  • Provides a shutdown procedure that resets the PSF – SIP states and deallocates the memory allocated by PSF – SIP for its operation up to the time of shutdown.
  • Generates alarms to the layer manager upon finding failures during the PSF – SIP operation.
  • Generates debug prints if enabled by the stack manager.
  • Detects a standby protocol resource going out of synchronization.
  • Supports the Rolling Upgrade feature to upgrade the software, which allows upgrading a system to a new version of the software without taking the system offline or interrupting service.
  • Conforms to Trillium Advanced Portability Architecture (TAPA)
  • Benefits of licensing Trillium software from Continuous Computing

PRODUCT INTERWORKING

Trillium PSF- SIP software interworks with the Trillium SIP protocol, protecting it from failure, the Fault-Tolerant / High-Availability (FT/HA) core software, and the Distributed Fault-Tolerant / High Availability (DFT/HA) core software.

CONFORMANCE

Trillium PSF-SIP (FT/HA) software conforms to Trillium Advanced Portability Architecture (TAPA) and Trillium FT/HA framework standards. Refer to PSF-SIP (FT/HA) functional specification for a detailed implementation description.