How is FLEX-E different than conventional Ethernet transports?
FLEX-E has several advantages over conventional Ethernet. Conventional Ethernet transport pipes frequently carry traffic from various customers but that traffic shares the capacity of the overall transport medium. Frames are intermingled and buffering and queuing occurs as part of that process. There is no specific segment of the Ethernet transport that is dedicated to any specific customer or application. This can have various effects on the traffic such a lower TCP throughput or higher Packet Jitter. FLEX-E allows specific sections of the Ethernet transport to be allocated to individual customer's traffic or application, much in the same way that SONET/SDH Virtual Concatentation (VCAT) allocated uniquely configured container sizes or DS1/E1 allocated specific DS0 channels per customer. Each customer's traffic will always be transmitted and received within the specific configured location, within the physical transport pipe. This helps reduce issues caused by buffering and queuing by network elements. Due to the explicitly configure transport size, bursting over the allocated bandwidth is impossible and data would lost if the transmission rate exceeds that which was allocated to FLEX-E Client. FLEX-E also allows the provider to use multiple physicals pipe to create one larger logical pipe. For example, two 100GE physical ports can be used as one 200G logical pipe where data can be allocated to a client on one or both physical ports. This allows for the creation of non-standard Ethernet sizes or the use of lower speed optics as a cost saving measure. This gives the service providers enhanced flexible in their Ethernet transport networks, hence the name FLEX-E for Flexible Ethernet.l