Current Technological advances as well as conveniences call for the Software Systems to exhibit Reliability at the same time High Availability (uptime being 99.999%). Consequently SW Designs and Methodologies mandate the need of SW being Redundant i.e all services as performed by the System SW must be running all the time regardless of any failure within. This implies the fact that the SW components should maintain the concept of "Active" and "Backup" entities. And upon the detection of a failure a "Backup" entity must "Switch over" to become the "Active" entity to continue processing as usual.

It is also important to consider the flow of information in a Software system, which can be classified as the "Control Path Flow" and the "Data Path Flow". A Redundant SW must make sure that both of these Flows maintain Redundancy. This in turn calls for the "Data Synchronization" and "Data Coherency" among the SW components.

In the presentation Mr. Ray will illustrate how to apply the above concepts to exhibit SW Redundancy in a typical "Packet Processing Equipment" being used in the Internet. In addition he will show that this type of approach can be extended to other types of SW systems.

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About the Speaker

Vola Ray

Mr. Ray has over 17 years of Experience in Telecommunications/Networking SW Development for Embedded Systems in a variety of areas such as:

• Configuration & Management of IP Services such as IPSEC, VoIP, IPQoS
• Control & Management of IP/ATM/Frame Relay Networks using Embedded SNMP/HTTP Agent and MIBs,
• Bandwidth Provisioning for Users, QoS Provisioning Scenarios, MPLS Traffic Engineering Arch. based on RFC2547 (BGP-MPLS-VPN) scenarios,
• Implementation of High Availability SW to support Fault Tolerance/Redundancy
• Device Driver Development under VxWorks
• Switch Configuration & Performance Monitoring of Chassis based Switches
• Config-File based Load/Save Mechanisms for Fast Auto-Configuration of a Switch
• Call Processing, Q.931 based Finite State Machines Implementations,
• Event-State Model Implementations for Complex Chassis/Boards Management,
• Packet Switching, ISDN (Q.931 Signaling) Protocols, etc.
• All of the above includes Chassis based products having a Control Card and a variety of Line Cards

During the 17+ years he worked for Companies such as GTE Communications, British TeleCom, ALCATEL Data Networks, Copper Mountain Networks, Tut Systems etc. Currently Mr. Ray works for Advent Networks.