Misordered frame delivery in connectionless MANs

Some packet switching networks do not inherently guarantee the ordered delivery of packets from one node to another if a connectionless service is used. This is generally due to the dynamic selection of routes be tween any two communicating nodes. Solving this problem is particularly important in connectionless Metropolitan Area Networks (MANs), such as the Switched Multimegabit Data Service (SMDS). After a brief discussion of this issue, we propose a simple mechanism that ensures the ordered delivery of packets in such misordering networks.