Session timeout

A session timeout is a limit on how long a signed-in session stays valid without activity, applied by web terminals, client portals and programming interfaces. When it expires the session is ended and the next action requires signing in again; it is an authentication lifetime, not a trading event. It is worth separating from a lost connection to the trading server, because the two look similar on screen and mean different things. A timeout ends the session in front of the reader — nothing on the server changes, positions stay open and orders already accepted stay live. The practical consequences are on the input side: a page left open may show figures that were true when it was loaded, an interface key or token that has expired will have its requests refused until it is renewed, and work typed into a form can be lost when the session behind it has already ended.