28 What Is SuperKermit?

When the Kermit protocol was first developed in 1981, it had short packets and did not use sliding windows, but the design was deliberately extensible to allow for the addition of these and many other features later.

A couple years later, when we defined the protocol for long packets and sliding windows, somebody somewhere started calling it "SuperKermit". Really, there's no such thing -- Kermit is Kermit. It's an extensible protocol in which the two file transfer partners negotiate automatically about what features they have in common and agree to use them.

All modern Columbia Kermits support long packets and sliding windows (except IBM Mainframe Kermit does not "do windows" because it exists only in a half-duplex environment, whereas full duplex connections are needed for sliding windows). They also support compression, single and locking shifts (for moving 8-bit data efficiently through 7-bit communication channels), file-transfer recovery, dynamic packet lengths and timeouts, and all sorts of other advanced and serious features that whoever coined the term "SuperKermit" never dreamed about.

Usually when BBSs or non-Columbia communication programs refer to "SuperKermit" they mean a 1985-vintage implementation of the Kermit protocol that implements a primitive and not very robust form of sliding windows, usually not in combination with long packets. However, if it is properly implemented, it should interoperate successfully with any other Kermit implementation, no matter how advanced or how minimal. That's the whole point of Kermit protocol.