THE WAY I SEE ITWaiting: a necessary part of life

Just as dirt collects in crevices, buffers collect in the interfaces between systems. It is their natural home, and life would not work without them. I have become fascinated by buffers. I see them everywhere I look. They cannot be escaped. What is a buffer? It is a holding space between two systems, sometimes in space, sometimes in time, allowing the objects or information from one system to await the next system. The pages of this book are a buffer, holding thoughts and ideas as printed words, awaiting the time that a reader peruses them. Waiting rooms are buffers, as are memory systems, holding the information generated by one system until the next can make use of it. Whenever two systems must interact, unless every event of one is perfectly synchronized with the events of the other, one system is going to have to wait. If the receiving system is ready first, it must delay, waiting for something to happen. If it is ready last, then if earlier arriving events are not to be lost, there must be a memory system to hold them. These memory systems have a variety of names depending upon the domain: memories, queues, buffers, inventory, waiting rooms, stock, and even books on a bookshelf (awaiting readers), food in the pantry (awaiting cooks and eaters), and any items that are stockpiled, awaiting use. Problems arise at interface, any interface, be it person and machine, person and person, or organizational unit and organizational unit. Any place where two different entities interact is an interface, and this is where confusions arise, where conflicting assumptions are born and nourished, where synchronization difficulties proliferate as queues form and mismatched entities struggle to engage. To the analyst, such as me, interfaces are where the fun lies. Interfaces between people, people and machines, machines and machines, people and organizations. Anytime one system or set of activities abuts another, there must be an interface. Interfaces are where problems arise, where miscommunications and conflicting assumptions collide. Mismatched anything— schedules, communication protocols, cultures, conventions, impedances, coding schemes, nomenclature, procedures—is a designer’s heaven and the practitioner’s hell. And it is where I prefer to be. In the brain, queues manifest as memory systems, holding information as it passes from one set of processing units to another. Memory systems must therefore reside at every interface, although they may not be recognized as such. Anything that maintains a trace over time is a memory system, so even the red mark on skin after a scratch is a memory system of sorts, even if the role it plays is nonfunctional. Inside the brain, however, visual and auditory short-term memory systems coexist with shortand longterm memory systems. All perceptual systems must have memory structures, all motor control systems, all things that interact. If perception or thoughts take place at different levels of processing, then memory systems must handle the problems of synchronizing the events. Hence the proliferation of human memory systems, with new ones seemingly discovered every year: short term, working, semantic, procedural, declarative, implicit, explicit, and what have you. There must be equivalents in the motor system, maintaining shortand long-term memories of muscle actions, limb positions, and control signals. In services, queues are lines of people waiting to be served, sometimes orderly, sometimes unruly, sometimes sitting patiently in waiting rooms. In the hospital, it is people in waiting rooms, patients staying in recovery rooms or intensive-care wards beyond the time required while awaiting an empty room, in te ra c ti o n s M a y + J u n e 2 0 0 8