Making Your Own Crossover Networking Cables (Update)...

Making Your Own Crossover Networking Cables UPDATE

Last night, or earlier this morning, I posted about F-I-N-A-L-L-Y getting around to making my own crossover networking cable using a length of CAT 5e Ethernet cable, two RJ-45 connectors, and the Klein Tools crimper/stripper that I had bought from Home Depot a couple of weeks ago.

How did I do? I will get to that in a moment.

For those who do not know, here is a brief review.

There are two types of Ethernet cables used in computer networking.

• Straight-through Ethernet cable
• Most commonly used Ethernet cable.
• Typically used to connect different devices, such as a host to a switch.
• Uses the T568-A standard.
• Crossover Ethernet Cable
• Used to connect similar devices.
• A host to a host.
• A switct to a switch.
• A router to a router.
• Uses the T568-B standard.

T568-A and T568-B Cabling Standards

Making your own Ethernet cables can be a frustrating exercise.

When I was taking the in-person class for the CompTIA A+ certification at UMBC a few years ago, each student was given a short length of Ethernet cable, two RJ-45 connectors, and a cutter/crimper. We were instructed to make our own Ethernet crossover cable. That is, one end of the Ethernet cable had to be set to the T568-A standard, while the opposite end had to be set to the T568-B standard.

More to follow.

I will probably end up re-writing this post.

Creating a Table Depicting Types of Ethernet Cables Using HTML...

Creating a Table for depicting the Different Types of Ethernet Cables

For this post, I am going to make an attempt at creating a table about the different types of Ethernet cables using HTML.

I am going to base the my table on "Table 2-2 Examples of Types of Ethernet" found on page 37 of the CCNA 200-301 Official Cert Guide Volume 1 by Wendell Odom.

Let's give it a try.

Speed	Common Name	Informal IEEE Standard Name	Formal IEEE Standard Name	Cable Type, Maximum Length
10 Mbps	Ethernet	10BASE-T	802.3	Copper, 100 m
100 Mbps	Fast Ethernet	100BASE-T	802.3u	Copper, 100 m
1000 Mbps	Gigabit Ethernet	1000BASE-LX	802.3z	Fiber, 5000 m
1000 Mbps	Gigabit Ethernet	1000BASE-T	802.3ab	Copper, 100 m
10 Gbps	10 Gig Ethernet	10GBASE-T	802.3an	Copper, 100 m

Comment:

It wasn't too difficult to create a basic table using HTML.

Yes, the end result is a little plain to look at.

I tried to add a grid around each cell. According to Blogger, in order to do that, I have to enable CSS on my blog. Apparently, it is easy to do so.

By enabling CSS on my blog, I can add further enhancements to the table to make it more visually appealing, such as making each alternating row a different color.

Therefore, I will enable CSS in the very near future.

Anything to make my blog better.

Meanwhile, I will add hyperlinks for each cell under the Formal IEEE Standard Name column.

That's easily done.

Making Your Own Crossover Networking Cables...

A couple of days ago, I reached section "1.4 UTP Cabling" in the "Network Address and Basic Troubleshooting" online course over at the Cisco Networking Academy.

As a result, I drove west down Bell Avenue to the Home Depot in Surprise, AZ.

While at Home Depot, I picked up a 100 foot length of Category 5e Ethernet cable by Southwire, a box of RJ-45 CAT 5e connectors and boots, and a Ratcheting Modular Crimper/Stripper/Cutter made by Klein Tools.

Ethernet Cable, RJ-45 Connectors, Crimper

These are items that I have been meaning to purchase for some time. Since I am making my way through the "Network Address and Basic Troubleshooting" online course, I thought that it was time to buy these items. I thought about buying a LAN cable tester, but I changed my mind at the last moment.

As I made my way through section "1.4 UTP Cabling", I eventually came to the section about straight-through and crossover cables.

The straight-through Ethernet network cable is the most commonly used type of networking cable. Straight-through network cables are used to interconnect different devices, such as connecting a host to a switch or a switch to a router.

Meanwhile, a crossover Ethernet cable is used to interconnect similar devices, such as connecting a host to a host, a router to a router, a switch to a switch, etc.

If you need to use a crossover Ethernet cable to connect a router to another router, for example, then you have to make the cable.

Creating a crossover cable entails stripping the Ethernet cable, separating the individual wires, re-ordering the wires, inserting the wires into a plastic RJ-45 connector, and then use the Ratcheting Modular Crimper/Stripper/Cutter to crimp the plastic connector.

When I took the class for the CompTIA A+ IT certification back at UMBC a few years ago, students were given a length of Ethernet cable, a crimping tool, and a RJ-45 connector. Creating my own crossover cable quickly became a mess.

How could something so easy become so difficult?

Well, when you create an Ethernet crossover cable, the wires have to be in a certain order for the cable to work.

That's where the infamous T568A and T568B wiring standards chart comes in.  

T568A and T568B Wiring Standards

To create that Ethernet crossover cable, one end of the cable has to meet the T568A standard and the other end has to meet the T568B standard.

When you buy a length of Ethernet cable, the cable is already at the T568A standard, so half of your work is already completed.

That just means that you have to get the other end of the cable to meet the T568B standard.

While writting this post, I found a short, informative video by Ideal Industries on Home Depot's webpage (just click on my hyperlink) that gives you a step-by-step guide on how to create an Ethernet crossover cable.

All of this information about how to create an Ethernet crossover cable is all well and good. However, there is a catch.

While reading "1.4 UTP Cabling", I read the following section:

Crossover cables are now considered legacy as NICs use medium-dependent interface crossover (auto-MDIX) to automatically detect the cable type and make the internal connection. 

 

Basically, what that means is that creating Ethernet crossover cables is now considered to be obsolete. However, that doesn't mean that Ethernet crossover cables are going away anytime soon. Given that there are millions and millions computers, printers, switches, and routers that are in use today, you will probably need to know how to make an Ethernet crossover cable for some time to come. New equipment, on the other hand, will have this new technology that allows them to function without an Ethernet crossover cable.

In the meantime, keep making those Ethernet crossover cables.  

They aren't going away any time soon.