Walls and Trust Nothing

At its simplest level the most obvious feature of the Walled Garden is the Wall. Walls have all sorts of connotations for us, especially at this moment in history, but they begin with protection. Being surrounded by a wall gives us a feeling of security and control over who or what can gain access inside and control as to what and who leaves. In its original use for a real garden the wall was much more about protection, shelter and providing the right environment for the plants and crops. The surrounding wall warms in the sun and raises the ambient temperature for plants in the north of the garden, it provides shelter from prevailing and strong winds and it organises the land separating it for management.

Do the walls around our information systems share similar nurturing properties?

Yes. You can make a case that treating the Wall as an interface, or inversely interfaces as walls lets the code within those walls consume and provide services and information specific to those interfaces (or walls). So this takes the metaphor of the Wall to mean more than what might have been assumed as an infrastructure and Enterprise defining concept.

But is this feeling of security really justified or is it actually a security blanket, merely comforting? If the wall is so impenetrable that nothing external can enter, even if invited by internal requests is that security, is that safer? Yes its safer, its how the world was prior to public internet and external services, each organisation, each installation of an organisation a locked down impenetrable lump.

Well, except when it wasn't, when the area outside the wali had its own perimeter space, a DMZ, a demilitarised zone with a public interface (probably to some packet switching network). In the DMZ files came in, files were dropped for external systems to pick up, probably using FTP