A huge floating mass of metal or a collection of units?
In my last article I talked about the need for a unique identifier for each Integrity Control Item (ICI). I am going to expand on that concept this time around. If you end up following this series all the way through, when you look back you will see that the IM is so critical to getting control of your project that without it, there isn't much chance of pulling it off successfully. It will, one day, seem obvious.
The Integrity Control Item is a very basic unit. It is used to represent the smallest practical unit in an Integrity Controlled project. What is meant by "smallest practical unit"? The way I like to think of it is to compare pieces to atoms. That probably sounds a little off the wall, but having a high interest in Physics, that comparison just makes the most sense. Let me explain.
Everything in the universe is made of something. Well, in theory anyway. I have a personal theory that once physicists followed the route of existence down from "rock" to "mineral" to "element" to "molecule" to "atom" to "electrons, protons and neutrons" to "quarks" to "sub quarks and gluons" we are in grave danger. I can just imagine the fateful day that some physicist in a high energy lab somewhere makes the discovery that the entire universe and everything in it is made up of absolutely nothing. Suddenly everything disappears, leaving the limitless vacuum that everyone seems to agree once existed. Sounds like a Douglas Adams story.
Like physical matter, everything in a project, no matter how complex that project is, is made up of something. The closer to that something you get, the less the things differ. A ship is a very complex system, but if you divide it into hull, deck and superstructure, it can be logically separated. Designating decks, compartments, on down to individual pieces of equipment give an even more detailed view. Now we are standing on the deck of a ship looking at a single bolt. Is that the smallest practical part of a ship? I would say it is one of many. In fact, if you think about what we just did, something interesting is going on. Call it Conservation of Complexity.
We started out imagining a ship. It is a single item. If you saw it coming into port, you would not tell someone "wow, look at that massive collection of steel plates, bolts, pipes, wires and paint!" You would more likely say "wow, look at that huge ship! How in the world does that thing float anyway?" But that is a different discussion. The point is that the ship you see pulling into port represents a single item, but an extremely complex one. Since the human mind is only capable of focusing on one or two items at a time, we see a ship, not all of the individual parts. But something weird happens. Once you start looking at it as a collection of parts, the overall number of items skyrockets. Instead of a ship, you have a hull, deck, and superstructure. And within that superstructure you have windows, doorways, passages, rooms, radar dishes, radio antennas, etc. If you were to examine a single room, you would find innumerable parts make it: steel plates, beams, insulation, pipes, wires switches, valves, and fixtures. If you were to examine the sink in a room you would find that it contains a myriad of parts as well: brackets, pipes, valves, screws, gaskets, etc. Examining the drain pipe would reveal individual sections of curved pipe to make up the trap, nuts to hold them together, gaskets to prevent leaks, a ball valve to close the drain, linkage to the drain stopper lever, and on and on. But have you noticed that although the number of things in the ship has grown exponentially by examining them at close range, their complexity has decreased. A single room is much less complex than a complete deck. A sink is simpler than a room, and a drain is simpler than the whole sink.
Yes, that is obvious, so what? Why do I care?
Because ships offer a very good model for software projects. Like projects, they are extremely complex, they require many people with many different skills working together in a very organized manner to slide into the water after having a bottle of bubbly broken on its bow. The effort required to plan the designs, procure the materials, control the order that things are built, make sure that steam lines are not run next to fuel tanks, and the millions of other details that go into building a ship is at least as great as the most complex software project. Yet ships do, generally get built and most of them don't just sink when they are launched. This fact offers hope to those of us who feel that software is just too complex to do correctly. So are ships, but they get built.
So how do shipbuilders handle the overwhelming complexity of their trade? In short, they choose simplicity over component size. They design things from the top down, but they keep working it until they get down to a "lowest unit" level. They may be building a hull, but they do it in small job-sized pieces. If a group of engineers got together one Monday morning to start developing a new ship design and for whatever reason decided that they would start with the sinks in the living compartments and work up to the overall design, how long do you think that would take? How correct do you think the designs would be? I think they would be very wrong indeed. Unfortunately since the design is from the lowest level to the highest, they would not discover that they had neglected to consider where the water for the sink was going to come from, or possibly the drain emptied into the fresh water tank below. In order to fix these problems, they would have to tear out huge sections of their work and constantly rework it. Sounding familiar?
Not that these things don't happen. My brother works for a major US shipbuilder as a welder. He told me an amazing story one day that illustrates that sometimes even shipbuilders get it wrong. He was working diligently to finish up a welding project on a wall insider the belly of a new ship. He noticed as he was working that another person was setting up a cutting torch and then just waiting. "Am I in your way?" my brother finally asked him. "Nope, go ahead.' was the answer. Half an hour later the same guy was still standing there waiting. Finally it began to bug my brother and he asked again, "Are you sure I'm not in your way?". "Nope, I can't start until you finish and get your work signed off" was the reply. "Oh, OK. What are you going to be doing?" Imagine the dismay when my brother heard his answer "Cut out that wall you are welding. We have a design change and that wall is moving." This may seem outrageous...OK, it IS outrageous, but if you really think about it, you have probably seen some comparable things happen in software projects.
Circling back around to Integrity Control Items, software projects are very complex, but one way of getting a handle on that complexity is to take a tip from shipbuilders and track each part individually. This is what IIs do for us in Integrity Management. They define a single unit (for example, a .dll file or a file server) and allow it to be treated, for the most part, exactly like any other unit. This greatly simplifies the day to day things that have to be tracked, but it also creates a large amount of data to be tracked. So, as was hinted at earlier, we have traded complex large items for simple, numerous small items. Like the cans of corn and bottle of salad dressing with UPC codes mentioned in an earlier article, we can now operate on these very different items with the exact same logic.
Hopefully this has gotten you thinking a little about how complexity can be conquered by decomposing the complex items into many simple items. Next time I will dive a little further into how this is actually done in the real world.
-M@
The Integrity Control Item is a very basic unit. It is used to represent the smallest practical unit in an Integrity Controlled project. What is meant by "smallest practical unit"? The way I like to think of it is to compare pieces to atoms. That probably sounds a little off the wall, but having a high interest in Physics, that comparison just makes the most sense. Let me explain.
Everything in the universe is made of something. Well, in theory anyway. I have a personal theory that once physicists followed the route of existence down from "rock" to "mineral" to "element" to "molecule" to "atom" to "electrons, protons and neutrons" to "quarks" to "sub quarks and gluons" we are in grave danger. I can just imagine the fateful day that some physicist in a high energy lab somewhere makes the discovery that the entire universe and everything in it is made up of absolutely nothing. Suddenly everything disappears, leaving the limitless vacuum that everyone seems to agree once existed. Sounds like a Douglas Adams story.
Like physical matter, everything in a project, no matter how complex that project is, is made up of something. The closer to that something you get, the less the things differ. A ship is a very complex system, but if you divide it into hull, deck and superstructure, it can be logically separated. Designating decks, compartments, on down to individual pieces of equipment give an even more detailed view. Now we are standing on the deck of a ship looking at a single bolt. Is that the smallest practical part of a ship? I would say it is one of many. In fact, if you think about what we just did, something interesting is going on. Call it Conservation of Complexity.
We started out imagining a ship. It is a single item. If you saw it coming into port, you would not tell someone "wow, look at that massive collection of steel plates, bolts, pipes, wires and paint!" You would more likely say "wow, look at that huge ship! How in the world does that thing float anyway?" But that is a different discussion. The point is that the ship you see pulling into port represents a single item, but an extremely complex one. Since the human mind is only capable of focusing on one or two items at a time, we see a ship, not all of the individual parts. But something weird happens. Once you start looking at it as a collection of parts, the overall number of items skyrockets. Instead of a ship, you have a hull, deck, and superstructure. And within that superstructure you have windows, doorways, passages, rooms, radar dishes, radio antennas, etc. If you were to examine a single room, you would find innumerable parts make it: steel plates, beams, insulation, pipes, wires switches, valves, and fixtures. If you were to examine the sink in a room you would find that it contains a myriad of parts as well: brackets, pipes, valves, screws, gaskets, etc. Examining the drain pipe would reveal individual sections of curved pipe to make up the trap, nuts to hold them together, gaskets to prevent leaks, a ball valve to close the drain, linkage to the drain stopper lever, and on and on. But have you noticed that although the number of things in the ship has grown exponentially by examining them at close range, their complexity has decreased. A single room is much less complex than a complete deck. A sink is simpler than a room, and a drain is simpler than the whole sink.
Yes, that is obvious, so what? Why do I care?
Because ships offer a very good model for software projects. Like projects, they are extremely complex, they require many people with many different skills working together in a very organized manner to slide into the water after having a bottle of bubbly broken on its bow. The effort required to plan the designs, procure the materials, control the order that things are built, make sure that steam lines are not run next to fuel tanks, and the millions of other details that go into building a ship is at least as great as the most complex software project. Yet ships do, generally get built and most of them don't just sink when they are launched. This fact offers hope to those of us who feel that software is just too complex to do correctly. So are ships, but they get built.
So how do shipbuilders handle the overwhelming complexity of their trade? In short, they choose simplicity over component size. They design things from the top down, but they keep working it until they get down to a "lowest unit" level. They may be building a hull, but they do it in small job-sized pieces. If a group of engineers got together one Monday morning to start developing a new ship design and for whatever reason decided that they would start with the sinks in the living compartments and work up to the overall design, how long do you think that would take? How correct do you think the designs would be? I think they would be very wrong indeed. Unfortunately since the design is from the lowest level to the highest, they would not discover that they had neglected to consider where the water for the sink was going to come from, or possibly the drain emptied into the fresh water tank below. In order to fix these problems, they would have to tear out huge sections of their work and constantly rework it. Sounding familiar?
Not that these things don't happen. My brother works for a major US shipbuilder as a welder. He told me an amazing story one day that illustrates that sometimes even shipbuilders get it wrong. He was working diligently to finish up a welding project on a wall insider the belly of a new ship. He noticed as he was working that another person was setting up a cutting torch and then just waiting. "Am I in your way?" my brother finally asked him. "Nope, go ahead.' was the answer. Half an hour later the same guy was still standing there waiting. Finally it began to bug my brother and he asked again, "Are you sure I'm not in your way?". "Nope, I can't start until you finish and get your work signed off" was the reply. "Oh, OK. What are you going to be doing?" Imagine the dismay when my brother heard his answer "Cut out that wall you are welding. We have a design change and that wall is moving." This may seem outrageous...OK, it IS outrageous, but if you really think about it, you have probably seen some comparable things happen in software projects.
Circling back around to Integrity Control Items, software projects are very complex, but one way of getting a handle on that complexity is to take a tip from shipbuilders and track each part individually. This is what IIs do for us in Integrity Management. They define a single unit (for example, a .dll file or a file server) and allow it to be treated, for the most part, exactly like any other unit. This greatly simplifies the day to day things that have to be tracked, but it also creates a large amount of data to be tracked. So, as was hinted at earlier, we have traded complex large items for simple, numerous small items. Like the cans of corn and bottle of salad dressing with UPC codes mentioned in an earlier article, we can now operate on these very different items with the exact same logic.
Hopefully this has gotten you thinking a little about how complexity can be conquered by decomposing the complex items into many simple items. Next time I will dive a little further into how this is actually done in the real world.
-M@
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