Networking Tools
This is a guide on networking tools.
Crimper
In this presentation, we'll take a look at the tool that you will likely use if you find yourself working with cabling and it's known as a crimper. Now, this is in many cases a multi-purpose tool that can strip, align and cut cables. But most notably, it's used for attaching the connector to the end of the cable. And this process is called crimping.
Now, when you have, let's say, Ethernet cable or category six cable, there are several small wires, copper wires, running inside the cable. And if you're doing a large wiring job, it's really not very feasible to just go to any given provider and buy a lot of precrimped cables. You certainly can do that, but they come in preset lengths and they're a little more expensive because they are already crimped. So when you're doing a new job, you really don't know what kind of lengths you're going to need. And it's a lot cheaper to just buy the cable so that you can cut whatever length you want and then of course crimp the ends on. So this tool makes this a lot easier. [Video description begins] A diagrammatic representation of stripped cable wires, placed alongside each other, inside a connector displays. [Video description ends]
So prior to crimping, the network cable jacket must first be stripped. And there are specific cable strippers as well, but most crimpers would have little cutting tools built into them to strip away that plastic jacket. And then the wires are aligned and placed into the connector.
So it's not very easy to see by this graphic, but the outline in black is essentially what the cable end looks like. And that's just a plastic cap with little metal contacts for the actual copper wires. And there are actually little plastic guide strips if you will, to make sure that the wires go into the right place. And a lot of crimpers again help you align those wires, so that they are already in place. And then you can just sort of insert the end into the crimping tool, and it opens up and clamps down onto the wire. And the rectangular portion that you can see within the cap is a piece that sort of juts out a little bit and exerts pressure on the cable so that you can't pull it back out. And in fact, most of them have sharp metal prongs so that they just bite into the cable a little bit but not enough pierce the jacket and actually hit the copper wire. So the connectors are secured permanently to the cable when it's crimped and essentially crimping really is just clamping down the connector. So that it snaps closed and bites into the jack a little bit and essentially that gives you a functioning cable.
Now that process is generally associated with Ethernet cabling, just because that really is still one of the most common cable types. But crimpers also exist for coaxial, and fiber connections, and many others, in fact. It really depends on what type of wire you're working with. But, you will likely find yourself working with a few different types, if you do end up working in cabling. And certainly, a crimper will be one of your primary tools.
Cable Stripper
Now in this presentation, we'll take a look at another essential tool for anyone working in cabling, and that is the cable stripper.
Ultimately, a cable first needs to be stripped of its plastic jacket before crimping it onto an actual connector at the end of the cable. When you're working with copper cabling especially, you have to expose the actual copper core. Because it needs to come into contact with the little metal plate inside of the connector. So once it's stripped, the exposed wires need to be aligned and put into the connector, and that of course is when you clamp it down or crimp it.
Now most cable strippers will have several different sizes depending on the cabling that you tend to work with. But if you think about a standard shielded twisted pair cable for Ethernet, this actually does have two different sizes. Because there's the plastic jacket around the entire cable, but if you strip that away, there are eight wires inside that are much smaller. And they need to be stripped away as well, because that's where you actually find the copper core of each individual wire. So again, depending on the type of wire that you work with most commonly, you can choose a cable stripper that has the appropriate sizes.
So again, there are numerous cable stripper types and designs depending on the cabling that you work with most often. So you would just want to verify that it does support the sizes that you work with. For example, there are cable strippers that are dedicated, if you will, to electrical cabling and that would be a different size. So, just make sure that it accommodates the cable that you work with, and many models consist of a crimping tool, and a cable stripper all in one. So, it's a two in one if you will, and that's perfectly fine as long as you're happy with it, and it works, and it is again the correct size. That saves you from having to carry around two tools.
Multimeter
In this presentation, we'll take a look at the multimeter, which is an electronic tool used to measure voltage, amps, and resistance, among a few other things. And you might sometimes hear this referred to as a volt-ohm meter or even a volt-ohm-milliammeter. But essentially it's just to test electrical current to verify it's running at the correct values, or if it's present at all. So you probably won't use this a whole lot in terms of just day-to-day PC troubleshooting. But if you are working a lot with power supplies, then certainly this is an invaluable tool.
Now in terms of voltage, when working with the standard power supply units that you'll find in a computer, there is both alternating current and direct current. Now, alternating current is essentially what comes in to your house, for example, or to an office building. This is the type of power that simply travels over the power lines because it can go a lot farther in terms of distance before it degrades, than direct current can.
Direct current, or DC, provides constant voltage or current, and it's typically used when you have a device that has its own dedicated power supply. So again, the AC would quite literally be the wall jack, for example, in your house. But then when you plug your computer into that, the power supply of the computer converts it to direct current to directly feed the components of the computer.
Because we don't have to worry about distance once the power is into the computer, if you will. It only has to travel a very short distance to the individual components inside. But it's good to know that you have the correct values in both cases. And here in North America, anyway, the voltage coming into any given plug should be somewhere between 110 and 120 volts. Then the direct current going into the components varies quite a lot depending on what the component is.
So in terms of the device itself, it has a display which typically has a four digit display because there are sometimes decimal places. And the selection knob is used to switch between the different readings, so specifically particular ranges of voltage, then maybe the overall current, the amperage. And then you might find a setting for resistance, or how much friction there is in terms of any given connection. And then of course, there are physical ports, which allow the probes to be plugged in. That's the red and black wires that you see at the bottom. And that's where you attach them to the actual electrical components to get the reading.
So again, this is typically something you'll find if you are working a lot with power supplies, but again, not something that's particularly common in just day-to-day PC troubleshooting.
Tone Generator and Probe
In this presentation, we'll take a look at another useful tool known as the tone generator. And this can be especially useful if you find yourself in an environment where you did not do the wiring, or perhaps more to the point, it's just not labeled.
So you might still have a central wiring closet where all your switches are, but you don't know where the other ends are. So this simply means that you have to run around trying to figure out where the other end of the cable comes out. So this allows you to identify the end points of those cable runs because you can place a tone on the end of the cable.
Now it's really just a magnetic field that is generated, but that travels down the cable and then it can be used to locate the other end of the wire. Now that is accomplished by using the probe. You carry that around with you and you literally place the probe into the wall port to trace the tone it picks up on that magnetic signal. And once it finds it, it plays a tone or lights up, or does both to indicate that, yes, this is the correct wall port for the other end in that switch, then you can label it. So switch port one comes out in office five, or something like that.
Now, it can be a little time consuming because each cable end has to be probed individually. So, if you're in a very large office this can be time-consuming. But ultimately, it will allow you to map out all of the cable runs and you can also use this just to identify continuity in the cable. In other words, an unbroken cable would have continuity, a break in the cable would not. So if the tone does not make it all the way to the other end, you know that there is a break in that cable somewhere. But for the most part it's used for tracing those cable runs so that we can know where the two endpoints are.
Cable Tester
The next tool that we'll take a look at in this presentation is the cable tester and exactly as its name indicates this is a device used to test cable connectivity. For example, it can identify any missing pin connections or any breaks in the cable itself. So it verifies that the cable was set up properly, was crimped correctly and simply has the proper communication.
Now, you can see by the graphic that certain models would have more capabilities than others. The one on the left, for example, is able to test multiple cable types. Whereas the one on the right is probably just for a standard 8-pin Ethernet cable. But generally there would be at least two ports on the end where you would plug both ends of the cable in. It would then send a signal down each individual line and just verify that it's picking up on that signal on the other end. And each light would light up, provided you are getting a proper signal from end to end.
So in looking at how they work, you do generally have a basic cable tester and an advanced. And this really just comes down to what you need most of the time. But a basic tester really just tests for continuity. That's to verify a conductive path and that you have the correct wiring. Continuity is, simply can I get a signal from end to end. So it identifies, again, breaks in the cable, or just a missing connection, or if the sequence was incorrect.
An advanced cable tester measures some more detailed signal transmission properties such as the resistance, or the ohmage value, the signal attenuation which is how much it degrades, or the levels of susceptibility to noise and/or interference on that cable.
So again it depends really on what you do most of the time. In most cases, the basic tester is usually fine. And this really can eliminate a lot of troubleshooting as you can just flat out say, yes it's the cable and just replace it with the new one and generally that should correct your problem. But if you do need those more advanced properties then certainly go with the advanced model.
Loopback Plug
In this presentation, we'll talk about a loopback plug, which you may also hear referred to as a loopback adapter. But I do want to quickly clarify one thing. If you are talking about configuring an IP address on a system, you may sometimes hear people refer to the loopback address or they might even say the loopback adapter but that is a very different thing. That's an actual IP address of 127.0.0.1 that is used for testing and diagnostic purposes, but it's entirely a software aspect. A loopback plug is a physical plug, as you can see by the graphic. It's something that you actually insert into a physical port. So in that regard, it's very different from the loopback address.
So this device is used to test the physical port. To see if there's any problems maybe with the contacts in that port. And you can find loopback plugs for serial ports, parallel ports, USB connections, or what we're seeing in this example, a network interface.
Now, in this particular case, the device can be made using an RJ-45 connector, a crimping device, and a little bit of unshielded twisted pair of cabling. And essentially, the cable just goes from one side and loops around and comes right back to the other side. So there's no cable that comes out of it in most cases. Although you might see some that does have a little bit of exposed wire, but it literally loops right around.
Now that's not the same as a crossover cable. Crossover cable is a complete cable and on basic appearance, it doesn't look any different than any other network cable but it's wired differently.
With standard Ethernet cable, there are eight wires in total, but four them transmit and four of them receive. So this is what you're seeing with the loopback plug, four wires just go out and then loop right around and come back in the other four connections. With a crossover cable, they switch the order so that you essentially can connect two computers directly to each other without the need for a switch for those to communicate. So it essentially crosses over the four at some point in the cable so that they come out on the other end. And that allows you to send directly to the receivers of another system and receive from the transmitters of the other system.
Normal cables don't do that, they don't crossover. So if you took a regular cable, and tried to directly connect two computers together, you would be transmitting to the transmitters on the other side. And you'd try to be receiving from the receivers on the other side, so that doesn't work. That's where our crossover cable comes in to play. And the device is classified as essentially both male and female, because it serves both purposes of transmitting and receiving.
So this is what I was referring to in terms of the wiring literally looping back on itself. [Video description begins] A diagrammatic representation of wiring in a RJ-45 Ethernet and Serial loopback plug displays. [Video description ends] Again, as mentioned, there are four wires that transmit, there are four that receive, so you just take those wires and you loop them right back. So you can see 1 loops to 3, 2 loops to 6, 4 loops to 7, and 5 loops to 8. And that allows you to test the network interface itself to see if there are any issues.
And of course, this is a very low-cost device so you can obtain them very easily and even make them yourself. But it does typically use some kind of sort of software to send and receive data to validate the port. Simply plugging it into the port in and of itself doesn't really do anything. There's no kind of programming built into the device so you generally use this in combination with diagnostic software to ensure that the network interface itself is functioning properly.
Punch Down Tool
In this presentation, we'll take a look at a tool known as a punch down tool, which you may also hear referred to as a krone tool.
But before we even get to the tool itself and its use, I do want to talk about why you even need this kind of tool. And if you think about walking into an office and let's say you have a laptop with an Ethernet connection, then of course you can just take a cable and you can plug your laptop straight into a wall port. Then on the other end, there would be a switch connecting all of the wall ports. But of course, in between those two points, there is a cable running through the walls.
So, it's the wall port that you are plugging into that has the receptacle and then some kind of centralized patch panel or punch down block. And I'll talk about those in greater detail in a moment, that allows all of them to be centralized in one place. But there is still Ethernet wire running through the walls to get you to that centralized wiring closet. So it's the ends of those cables that are running through the walls that need to be wired to the receptacles. This is where you find the punch down tool. So it's used to connect the wires themselves to a patch panel, a punch down block, a keystone module, or a surface mount box.
Now as mentioned, for each of those, a patch panel is simply a centralized location where all of those wall jacks come together. So let's say there are 100 offices and they are scattered all throughout the floor of any given building. Typically, there's a center or central wiring closet where they all just end up. So that's just quite simply someplace where you can ensure that everything's in the same place. So that we're not having to set switches up all over the place. So they all get into this central wiring closet. So all of those loose wires have to come together somewhere. And the patch panel really is exactly that terminating point.
Now if you were to look at it face on, it would look kind of like a switch, but there's nothing going on with a patch panel. It's just the other end of the cable centralized into usually a rack mountable interface. But if you walk in behind the rack, for example, all you would see would be wires connecting through to the receptacles. And those essentially are where you use the punch down panel.
Now, a punch down block is similar. But it's usually used to just connect loose wires together from let's say, coming in from one side and another side to extend the wire. So a patch panel actually has an RJ-45 receptacle. So you could plug an Ethernet cable and that's where you run the cable to the switch. But a punch down block would not have any receptacle. It would just be bare wires on one side to bare wires on the other side, so that you can usually extend the length of the cable.
The keystone module is the other end, it's the wall jack. So if you were to just pull the wall jack out of the wall, you'd see a little square box, if you will, on the inside where the wires are actually connected. That's the keystone module, and a surface mount box is essentially the same thing. It has that wall jack, but it's not mounted into the wall, it's exterior. So you just have a larger box that contains that RJ-45 receptacle, the female side, and it's just mounted to the wall so it's not recessed.
So in terms of preparing the cable, you certainly do have to remove the cable jacket to expose a few inches of the internal wires. But you actually don't have to strip the wire. There are little metal blades, if you will, in between each of those slots that kind of cut into the wire and come into contact with the copper core. But what you have to do is get them punched down into those little slots. They're fairly tight, it's just held in with friction. But it's pretty difficult to just do with your hands, because there's not much space, especially, in that centered channel.
So the punch down tool goes in between those two little, I'll call them towers if you will, where you insert the wire and then you literally just press it down. So you just fan out the cables, straighten out the ends, and place the wires into the appropriate places. And they should extend out a little bit, you don't have to worry about losing a little bit of the cable. Because when you punch it down, it inserts it all the way down. It bites into the wire and makes contact with the copper core, and it also cuts off any excess wire.
So you want to try to make sure that you do this as straight down as possible so that you don't cut on a bit of an angle. But the tool should make a little bit of a clicking sound when it's all the way down. And that also cuts off the excess wire so that ultimately, you get a nice clean connection as you can see here. [Video description begins] A diagram displays a jack containing wires that have been neatly inserted and trimmed. [Video description ends]
So inspect each wire to ensure that there is no overhang. Ensure that all of the wires are securely in place. And if there is still a little bit sticking out, you can certainly trim that off using any kind of wire cutter. But ultimately, that allows you to make all of those connections without having to strip each one of those wires. And basically, again, that's the receptacle end so now you can plug an Ethernet cable into that.
WI-FI Analyzer
In this presentation, we'll take a look at the Wi-Fi analyzer, which is a tool that you might find yourself using if you need to really optimize the coverage of fairly large area with Wi-Fi. So it's used to discover problems and optimize performance so you can find specific locations where maybe you might be a little more prone to errors, or interference simply because you don't have a strong enough signal. So you can test the antenna location, and of course its ultimately installation as well. But quite literally, it just informs you that this particular area has good strength and good service. While this area that maybe is a little more shielded from the source itself is a little more prone to errors and interference.
Now, when you are working with Wi-Fi the signal is divided up into channels. These are just radio frequencies and we are all familiar with channels on our radio. But a channel is not one specific frequency, it actually covers a little bit of a range of frequencies. And each channel overlaps a little bit with its adjacent channels. So channel 1 overlaps with 2, 2 overlaps with 3. But if you go to 1, 6, and 11, these channels are far enough away from each other that they don't overlap.
So those are pretty commonly used. And this essentially allows for better signal quality and less interference. So Wi-Fi analysis can reveal which channels are used the least. And ultimately, this information that you can gather up is very useful for optimizing the Wi-Fi. So again, we see where this signal strength is best. We see which channels are used the least. And then for certain areas we can say, well, let's configure these channels to be used here and those channels to be used here. And hopefully, you can end up with an optimal configuration for your Wi-Fi and ensure you've got the best coverage, with the least interference.