We need to begin a debate of the terms for robustness. The following by Radhika Roy of AT&T is a first set of definitions for your review and comment.

Note: The following definitions are a part of the document referenced below:

Study Group 16 Delayed Contribution: D.225 (WP 2/16)

Santiago, Chile, 17-28 May 1999

Question(s): 13/16

SOURCE*: USA

TITLE: Framework for Reliable H.323 Gatekeeper Architectures

AUTHOR: Roy, Radhika [rrroy@ATT.COM]

Reliability: To have the robust GK architecture for increasing reliability (e.g., appropriate redundancy in the architecture as well as robustness of the software codes). Availability: To provision the GK architecture with implications for both the planned (e.g., upgrading, maintenance, etc.) and unplanned (e.g., failures) outages of the GK itself or its components to meet the desired availability goal (e.g., appropriate redundancy in the architecture based on trade-offs between the planned and unplanned outages). Serviceability: To include provision for outage tolerances in the GK level architectural framework to meet the service level requirements (e.g., if 24-hour a day, 7-day a week, and 365-day a year is the requirement for the GK, the GK architectural scheme can be provisioned with redundancy to meet the requirement considering the outages). Recoverability: To keep proper provision within the GK architecture for the recovery time as well as for any signaling messages that might have been in transit at the time of failure Scalability: To be able to increase the throughput by the GK architecture as more resources are put to the system considering the fact that a GK might be used by a large user community (e.g., capability to provide automatic load balancing within the GK architecture with proper redundancy considering outages). Context: To be able to maintain context across multiple requests with minimum latency within a session by the GK architecture in view of outages. Security: To provide adequate security with redundant GK architectures in the event of failures as well as during replications.

-- maureen

Maureen Stillman Member of Scientific Staff Voice: (607)273-0724 x62 Nokia IP Telephony Fax: (607)275-3610 127 W. State Street Mobile: (607)227-2933 Ithaca, NY 14850 e-mail: maureen.stillman@nokia.com www.nokia.com