1 -Reliable transmission is essential for several real-time applications. Backup Channels introduce the notion of availability at the cost of increasing the use of network resources. However, this over provisioning of resources is potentially wasted, since packet delays are usually lower than the required end-to-end channel delay. The goal of this paper is to present a new scheme for obtaining the primary and backup paths maximising the admission of channel in a network
This paper uses a new failure detection scheme for selecting the primary and backup paths denominated Proactive BackupChannel. This scheme is based on activating the backup channel before a fail is produced. The experiments show that using this new scheme the admission rate (the number of channels a network can accept) is improved considerably.The paper also presents the application of this scheme to IP networks using TCP trunking.Quality of Service; Dependable Networks; Routing; TCP trunking.;
I. INTRODUCTIONSeveral distributed real-time applications need a reliable transmission: telesurgery operations, real-time guidance and control, critical experiments in dangerous environments (nuclear and biological), tele-conference, etc. Service disruption for even a short duration could be catastrophic for this type of applications. The real-time requirements and dependability issues often conflict, resulting in a trade-off situation [1]. For example, increasing the reliability of a realtime transmission using packet retransmissions may increase the end-to-end delay so a packet misses its deadline. In many ways, the concept "Quality of Service" (QoS) already represents the concurrence of many fault-tolerant and real-time services [2]. That is, real-time distributed applications require Quality of Service guarantees on timeliness of message delivery and failure-recovery delay.
