Abstract: Event logging methods and systems for communication networks are provided. Events associated with particular communication sessions are logged responsive to detection of any of a plurality of event logging triggers which have been established for the communication sessions. Per-session event logging according to embodiments of the invention may provide improved event logging functions for communication network fault or error analysis by enabling enhanced trigger-based event logging control and logging of a wide range of events, including standards-based signalling messages, at network elements throughout a communication network.

Abstract: A method and device for recording call failure information in a data transmission system is provided. The failure logs generated in response to a failure event include a failure type and a first timestamp. A log record is created for a first failure log based on the failure type, and storied in a log record storage. Whenever a further failure log is generated in response to the same failure event, the further failure log includes said failure type and a current timestamp, so that it will receive the same identifier. The log record is updated to document the current timestamp.