Ethernet has proven to be the early leader in AdvancedTCA. The many Ethernet and related specifications can make it difficult track which ones are important for a particular application. With the advent of CompactPCI 2.16, and now AdvancedTCA, system designers must become more familiar with networking to select a switch for their system. Requiring the system’s switch to support every Ethernet specification greatly increases the cost of the switch by requiring potentially unused features. Some of these Ethernet specifications define important features for AdvancedTCA, while others can be desirable, and still others are unnecessary for most AdvancedTCA systems.