What is a booted cable?
A "booted" cable is a cable that has a molded "plastic" boot that fits on the cable end of the connector and a portion of the cable itself. Sometimes a booted cable is also referred to as a "strain-relief" cable, which is exactly the purpose of the boot…
There are two main types of boots that you will encounter, a separate boot that you can purchase to put on a cable that your are making on your own, or when you buy a manufactured cable that has its own injection molded boot.
The manufactured type is more robust as it provides support at more parts of the connector than the pre manufactured type. As you can imagine the main reason for the boot is to protect the cable and connector from the cable itself being pulled while the connector is engaged in a switch, PC, patch panel etc. If a network cable is pulled, by accident or during installation, it can become damaged. The issue is that the damage may not be apparent to the eye, just one wire could be damaged but the cable itself appears normal.
So what is a “snagless” boot
When an Ethernet cable is referred to as “snagless” it means that there is an extra part of the boot that covers the end of the locking tab. There are two common types of protector you will encounter; bubble and Ferrari.
The locking tab is easily damaged, one of the most common ways to do so is when pulling a cable through a bunch of other cables. If there is no protection for the tab then the tab will become stuck on another cable and break off, rendering the cable useless.
What is a crimped (or assembly style) cable?
Technically every network cable starts its life as a crimped cable. The outer jacket of the cable is stripped to the required length, the internal wires cut to the right length, put in the right order, and the connector placed on the end of the prepared cable. Once the connector is in position it is fixed on the end by "crimping" the gold connectors into the wires, and also pushing a plastic bar inside the connector onto the cable jacket that is inside the connector for stability.
When you use this type of cable there are some advantages and disadvantages. As you can imagine the crimped type is slightly less expensive than its booted counterpart, but the actual difference in price is minimal, sometimes only a couple of pennies depending where you buy them from.
The crimped type has no strain relief capabilities, or protection for the locking tab on the connector. But there is one advantage to crimped cables… They are very suited to high density applications such as patch panels. If you have a 96 port patch panel with 96 patch cables connected to it, things are going to be a bit tight! If you are using molded booted patch cables you may run into a couple of issues…
The point at which a crimped cable is flexible is right at the point the cable exits the connector, this is not the case with a booted cable, you have the additional distance the boot takes up before it becomes flexible. This may not sound too bad, but this can make a big difference in a couple ways. The cable will protrude further from the patch panel, due to the boot, which may make it difficult to fit into existing cable management, or could even mean that the door to the rack will not close. Additionally the locking tab may be difficult to disengage on a booted cable in our patch panel scenario, the extra room the boot takes up can make a difference between being able to press it in enough to release the connector or not.
A word on choosing the length of a patch cord...
We are mentioning this point in this article because the differences we have just described between booted and crimped play part in choosing the correct length of patch cable for your application. Everyone who is building a rack or multiple racks in a data center want to make a good job of the cable management, untidy cables are painful to look at and are also a reflection on the installer themselves. We have seen installers meticulously measuring distances between patch panels and equipment with just plain cable, string etc. to work out exactly what lengths to order, but this approach usually ends badly.
The length of a patch cable is measured from the end of one connector to the end of the other connector, not the length of the cable without the connectors. So why mention this in an article about booted vs. crimped cables? Well as described above, a booted cable does not flex as soon as the cable emerges from the connector because of the boot, the length of the boot is obviously part of the overall length of the cable itself.
So getting back to our installer who has just worked out he needs 300 3ft patch cords… When he comes to install them he suddenly finds out that hardy any of his patch cords are long enough! Whether the cord is crimped or booted (But especially when booted) you cannot measure the distance you need by simply measuring the distance between the two as this does not take into account the length that is wasted by the amount of that length that is taken up before the cable can start its journey to the device it is connecting to.
The best way to work out the needed length is simply measure as described and add 6 to 12 inches to your measurement. It will not matter that the cables will work out longer in some instances, as long as you order the same lengths it will be easy to produce a tidy and symmetrical result.