Network Cabling Testing (for home)

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Evo said:
sorry if I came across rude

Not at all, definitely not my intention to imply.

Many thanks for your's and other's help.
 
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Tom.G said:
30 feet of interior coax

Which is not ethernet. The Cable connection has a variety of modulation schemes of varying speed to handle degraded signals. This is just not the case with Ethernet. The highest speed supported by both sides will be attempted. If your connection is with bent coat hangers and both sides support 10Gbps then they will try that and you will not get a connection even if 10Mbps would work. You can however slow the connection down and it will use the slower speed.

stoomart said:
the issue there is likely one of the 4 wire pairs is not connected properly, because 100BASE-TX only uses two of those pairs, and 1000BASE-T uses all four pairs.

Also the pairs need to be pairs. If you swap the + wires of two pairs and not the - wires you will not get a connection. If the + and - wires of a particular pair are not actually paired in the cable you will only get a short distance before the connection drops out.

Most modern equipment doesn't care what pair goes to what pair on the other end as long as they are connected.

BoB
 
The best way to find out if your cabling was done right is to use a cable tester. This is what I use.
https://www.staples.com/Hvtools-Cab...r-Cable-RJ11-RJ45-HV251452CT-/product_2426541

If you don't want to do that, you can connect a computer at both ends and then do a sustained data transfer between the two and have the systems measure the bandwidth. If you're comfortable using linux (ubuntu live) then you can give this a try. Boot ubuntu on both systems, call them Host A and Host B

Host A will listen for a connection and Host B will connect and send a string of zeros several GB in length.

Host A
$ ncat -v -l 4444 >/dev/null &

this commands tells the system to run netcat. -v is the verbose flag so you see some messages. -l tells netcat to listen. 4444 is the port number to listen on
>/dev/null means whatever ncat gets, delete it without writing anything to the drive

Host B
$ dd if=/dev/zero bs=1GB count=5 | ncat Host_A_IP_Address 4444

dd is a copy program, if is the input source=a string of zeros generated by the processor, bs is the size of each chunk=1GB, and count is the number of chunks=5
we pipe the output (5x1GB chunks of zeros) into ncat and tell it to connect to Host_A
on port 4444
Host_B will send a 5GB string of Zeros to Host_A. Host A will immediately delete them. Host_B will then give you a summary of how much data was sent and how long it took.

The idea is that nothing touches the hard drive so you get a true measure of how fast your network links actually work.
This is the output from running the test between two of my systems.
5+0 records in
5+0 records out
5000000000 bytes (5.0 GB, 4.7 GiB) copied, 44.627 s, 112 MB/s


I know that I have Gigabit network cards on both systems and my router also has gigabit ports. So I expect my transfer rate to be running at 1Gbps.
My transfer rate was 112MB/s, which is apprx. 896Mbps. This is normal. You'll never get the full 1Gbps because there's always overhead.

P.S. Please keep in mind that even though you have cat7 cables that are capable of doing 10Gbps, your systems probably can only do a maximum of 1Gbps. As others have mentioned, 10Gbps equipment is enterprise grade and generally costs a lot of money (hundreds or potentially thousands of dollars).
Cat5e (or even Cat5 on a short run) can do 1Gbps so you may not actually see any difference at all in network speeds.
 
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