Multipath FEC scheme for the ATM adaptation layer AAL5

One approach to facilitate statistical multiplexing of bursty sources in ATM networks is dispersion of the traffic over independent paths. It has been shown within the literature that by dispersion of traffic over disjoint paths it is possible to increase the Quality of Service (QoS) (see e.g., (Maxemchuck, 1993), (Lee, 1993)). In multipath schemes without additional error control, the resulting QoS depends on the worst-case path. By using a multipath scheme with FEC (Forward Error Correction), it is possible to compensate cell losses. Using error correcting codes like Reed-Solomon-Erasure Codes (RSE Codes, (McAuley, 1990)), these schemes add redundancy and disperse the traffic using several transmission paths (Ding, 1995). Until now, protocols and implementation concepts suitable for a widespread use of multipath schemes are still missing, in particular for the widely used adaptation layer AAL5. We present a novel protocol MP-FEC-SSCS for AAL5 for employing a redundant multipath communication scheme especially suited to the UBR (Unspecified Bit-Rate) service. This presentation is complemented by detailed results for software implementations based on C++ and first results using Java, targeted for an active network implementation.