An apparatus includes an agent to facilitate communication in one of two or more modes, where a first of the two or more modes involves communication over links including a first number of lanes and a second of the two or more modes involves communication over links including a second number of lanes, and the first number is greater than the second number. The apparatus further includes a memory including data to indicate which of the two or modes applies to a particular link and a multiplexer to reverse lane numbering on links including either the first number of lanes or the second number of lanes.