The 38999 I/O interface was designed decades ago, when the primary concerns were ruggedness and field repairability. This connection had to be rugged to survive the harsh environmental conditions to which they would typically be exposed. These conditions included high vibration and mechanical shock levels, temperature extremes, hundreds of mating cycles and sealing of the contact interface against corrosive fluids and chemicals. Easy field repairability is also key as these systems are often deployed in remote locations where repair facilities are scarce and critical missions can be compromised with a system failure. The ability to remove and replace a damaged contact interface with readily available hand tools to restore system operation was a key part of the design criteria. Data transmission rates, however, were not a key consideration in the initial connector design.
As the need for a high-speed interconnect solution for this application has become apparent, the 10 Gbit-Ethernet protocol has emerged as the solution of choice.