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Understanding – Training for life.

Training has been a requirement for my line of work for several years. Taking new employees into a room for a day,  week, or even a month, and teaching them the ins and outs of their job, is one of my favorite parts of managing a team. I probably enjoy it the most because it pets my ego in a way that is hard to replicate in my other interactions. All the same, I have been told that I am proficient at the task and provide value to others when I perform it, so it is not entirely self-serving. For the past few years, I have worked for a company that provides internet services. Networking. The individuals who I have trained are network technicians and engineers. They are extremely intelligent, often brilliant people. They are usually experienced in their craft or have completed some form of formal education and received a prestigious certification. They almost certainly know more about the mechanics of our topics than I do. While I am again proficient, and can perform the task, an education in mechanics is not what I provide. My goal is give them understanding. These, in my opinion are two profoundly different things. 

In Networking, like most engineering disciplines, what can be created ranges from very simple to extremely complex. The technicians I work with are somewhere in the middle. Complex structures require years of training, and once built, can run without error for longer than we will live. These techs do not have the skills to build these complex structures yet, but they do support them. They also create less complex networks and configure devices to work within those complex structures.

Things that are taken for granted. Once training is complete, it is my hope that they will be able see things not just for what they are and how they are put together, but why they are that way. Why they matter. A common question asked on day two or three of training, as we transition from practical to conceptual is, “What is an MPLS network?” Some will answer by saying it is a Multi-protocol Label Switching network. Some will say is a private network. Some will not have an answer at all. I usually discuss this discrepancy in response for a little while, letting them know that all of those answers and may others are correct, with providing too much feedback of my own. I want them to talk and start to think. I digress to something simpler, something that I am certain that all of them have a firm understanding of at this point in their career, and don’t worry I will not go too far into this world of networking, for the analogies will get much more generic in just a moment. I ask them “What is an IP address?” Again I get the answer, an internet protocol address. The address that a device a on a network has. I may get someone who says it’s a set of numbers. Four sets of numbers, each between 0 and 255. Again all these answers are right and I ask, “What is a subnet?” This is a challenging topic for many, even in networking, but it is at the core of almost everything in the networking field. They might say a group of IP addresses, a range of numbers, or a confined space that limits traffic. All correct, but not the answer to the question I was asking. I ask for examples and write them on the board. They provide them easily and we discuss them. We discuss the details of why each number set matters. They know that a subnet will always start with 255. Something. Something. Something. They know that It will always get smaller as you move through the octets. At some point in the conversation, someone throws out the term octets. I jump on this statement as it is key to transitioning to a state of understanding. You see each number set in an IP address or a Subnet Mask is a set of numbers. All between 0 and 255 and separated by periods. Most adults today are at least remotely familiar with these addresses, aware of it or not, (Things like 255.255.255.0 or 192.168.0.1) or at least they know that when you go to a web site, there is some kind of number-address that you are really going to and some super techy kids can magically get to pages without using the name. But the term Octet does not make sense in these addresses. Octet means eight, and there is nothing visible related to eight in these numbers. To be clear, an IP address is a series of four Octets. That always true.* So most of the class will be able to tell me that the term octet refers to the fact that each set of numbers in an IP address is eight bits long. They will also tell me that a bit, in networking, is a number, either 1 or 0. This is true. Most networking is binary in its root. Binary meaning having only two possibilities. In IP Addresses, Bits are either on or off. This allows me to continue the conversation, and move back to my question, of what exactly is an IP address. They will now tell me, “A set of bits!” I ask how many. They think for a split second and say either 32 or four sets of eight. Again both answers are right. I ask how we get from bits to a number between 0 and 255. This is where we do some math. We switch to subnets because in this context subnets are easier to understand. To get from eight bits to the numbers we know we have to count and multiply. Every bit in an address is a possibility. Each possibility has two potential outcomes. Either on or off. I can give those outcomes values. Weights. When I know how many values or bits will be in the sequence I can give each bit in an order a specific value or weight, based not just on its state, 1 or 0, but also on its position. This is how you count in binary. We can learn this part together now. 

If there is one Bit, then your options are limited to two possibilities. We always start counting at 0.

0(a single off bit) = 0

1(a single on bit) = 1

If there are two bits then my possibilities expand and order begins to matters.

  • 00 = 0 (both bits are off, and we always start counting at zero.)
  • 01 = 1 (just like before a single on bit is one. It is also worth noting that the smallest bit is always on the right. That will make more sense as we continue.)
  • 10 =2 (do not look at this as Ten, look at as two bits. the left most bit is on, and the other is off. Off bits still have a value of zero, no matter where they are in the sequence.)
  • 11 = 3 ( here is where most get lost. To get three you must add the bit to the left, the second from the right, with the bit from the right, the other on bits. The leftmost bit has a value of two, the rightmost bit has a value of one. 2+1=3. We will continue this exercise below. )

Let’s pause and note a few things.

· First Note: with one bit, you have two options, but the maximum value is 1. With two bits you have four options with a maximum value of 3. This is because we start counting at zero. We will continue with three bits, then four.

· Second Note: if you are lost here, skip the section below and look for the word resume.

With three bits we can really start to get moving.

  • 000= 0 (all bits off)
  • 001 = 1 (this just repeating what we have already done)
  • 010 = 2 (hopefully this is making sense)
  • 011 = 3 (get it yet? Where do we go next?)
  • 100 = 4 (when we move to a new bit in the sequence, all the ones behind it get turned off, just keep going)
  • 101 = 5 (Third bit on is 4, first bit on 1. 4 +1= 5
  • 110 = 6 (because 4, the third bit, plus 2, the second bit, equals six)
  • 111 = 7 (4+2+1=7 we get this by now I hope.)

To form addresses on a network effectively we must need a lot of bits. There need to be a lot of addresses. At some point in time, some people got together** and decided that 32 was the right number of bits, and that trying to remember an address like 11111111101010101110101110000111 was not really possible for people. So they split it into four parts. That unruly number becomes 111111111.01010101.1101011.10000111. This is still hard. Bits are great for computers, not for people. So they decided to use the binary system of counting we have been suffering through, instead. Below an expert of the binary number system.

 
 

Ok, so this has been a lot of build-up to a fairly simple conclusion. I will ask the class, usually exhausted at this point. Again What an IP address is. I will receive exhausted answers. And IF I don’t get the one I am looking for I will state it outright.

An IP address is a string of ones and zeros.

That conclusion sounds silly, but the moment that the class understands it, is the moment they can truly start to understand their job, and their world in a new way. The questions continue.

What is an IP address? a string of ones and zeros. 32 bits long. Separated into four octets.

How do people read them? Well, we convert them to a decimal, so that we can read them. Four sets of numbers between 0 and 255.

Why 255 not 256? Because we start counting at zero.

How to routers and computers read IP addresses? Well, as a long string of bits. A really long string of bits.

There is new understanding now. They start to think about other things through this new lens of thinking. I ask again what a subnet mask is (those look like this 255.255.0.0). The class will think for a moment, then someone will provide the answer a want, A string of continuous on bits, or ones, followed by a string of off bits, or zeros. That number above, 255.255.0.0 is just 11111111.11111111.000000000.00000000. The conversation continues. We talk about networking concepts in more detail. Usually after a break, or even on the following day. We start to think through things that they knew but did not understand. It is amazing to watch these brilliant minds connect the dots of puzzles that they have struggled with for years. Finally starting to not just accept things as rules, because the book, or an instructor, told them it was so, but grasp why they must be that way. This understanding is in my own opinion what separates the greatest engineers and leaders from those who simply do what they must. It is my hope to build the former, not later.

After a lot of networking talk, I will put this into much better terms, while addressing another concern that I have for the way most education is delivered. I will ask the class again about an MPLS network. MPLS networks are complicated things, and while most in my classes have worked with them, few understand them. I ask them what it is. They still struggle. So… I ask them about a watch.

What is a watch? We have all seen them and used watches a million times, but do we truly know how to explain them to someone who hasn’t. What would you say? Watches are simple, but those questions can be applied to complicated technical concepts as well. Technical classes and education do not prepare you to answer those questions. If a technical manual for a watch existed and was written like most technical manuals I have approached, they would read like this:

A watch is a device that can be worn on the wrist or held in a pocket. It contains gears and requires a power source, often a battery. If designed for a wrist, a watch will have a band made of leather, rubber, metal, or other suitable materials. A clasp is included to allow the wearer to take the watch on and off. The gears inside the watch turn in complex, but precise patterns to turn two, three, or sometimes more needles on the face of the watch. The face is protected with glass of varying strength depending on quality.

This manual would describe and define all of the pieces and parts listed above. It would state the name of each gear, and the number of teeth on each cog. It would present different approaches to power the device, to tune it. Repair technics would be listed. There is so much you can say about watches. There is so much you can say about almost all topics. Just look at how much I spouted about IP addresses. I apologize for getting carried away there, It simply helps to make a point.

What most manuals never provide our engineers with one extremely critical piece of information: A watch is used to tell time.

In my experience, there are three types of thinkers in the world: 

  1. Those that can build and fix a watch without the knowledge that a watch is used to tell time. 
  2.  Those who are not able to perceive any other way but to describe their world, without stating its function. A watch is used to tell time. A car takes you places. A remote turns things on and off.
  3. And those who are able to understand the How and the Why as they examine life. The most successful individuals I have ever met understand the difference between these two ways of thinking and consider everything they encounter from both sides.

I make the attempt to apply both lines of thinking to all aspects of my life. To my emotions, to relationships, to work, all of it. These logic exercises can be exhausting, but once you are in the practice of examining your surroundings in this way it will be come the only acceptable way of thinking. 

My goal in each training session is not simply to teach the content covered in a book but to inspire those I am training to think about their surroundings in a way that will enrich the remainder of their life. 

*I am referring to IP V4 for anyone reading who would challenge that statement, for IP V6 is very different and while discussed in training, follows the same logic, but is not at all the same structure on a surface level.

** https://en.wikipedia.org/wiki/IPv4#History