 IEEE 802. 1w Rapid Spanning Tree Protocol (RSTP) for reconverging metropolitan Ethernet networks. Split-MLT is targeted at carriers looking for more reliability of Ethernet services than subsecond recovery time. Split-MLT is based on the IEEE 802. lab multilink trunking protocol, which is designed to enable backup links from a group of high-bandwidth trunks and traffic load balancing across those trunks. As such, Split-MLT enables service providers to configure redundant paths to a company or multitenant building without routing protocols such as Open Shortest Path First (OSPF) or the Routing Information Protocol (RIP). Split-MLT seeks to address three Ethernet reliability issues: link failure, node failure, and con- versation preservation and maximum bandwidth utilization. For link and node failure, Split-MLT makes a pair of aggregation switches look like a single switch to the rest of the network. If one node fails, Split-MLT ensures that the remaining node has the destination MAC address information to forward traffic on behalf of the primary switch. This is done on a per-session basis, which helps ensure conversation preservation. If one of the links Next-Generation SONET and Optical Architectures between the switches is lost, Split-MLT spreads sessions over the remain- ing working links; this makes more efficient use of available bandwidth by eliminating the wasted redundancy fiber that is used only if a failure occurs. Although Split-MLT might seem to be a more feature-rich alterna- tive to RSTP, it still does not provide the 50-ms recovery of SONET, which is the benchmark that every service provider considering Ethernet is shoot- ing for. The one-second recovery time of Split-MLT is the same for RSTP. RPR and next-generation SONET proposals such as Multiservice Provi- sioning Platforms (MSPP) are closer to what service providers are looking for in terms of Ethernet/SONET hybrids. In yet another approach, recent articles include the following: "There is a hot new product category emerging in the industry, 