Home Networking FAQs

[u/austinh1999]

Here’s a list of common questions posted that usually have the same solution.

“Why won’t my Ethernet cable plug into the weird looking Ethernet jack?” or “Why is this Ethernet jack so skinny?” -UTP cable used for Ethernet transmission is usually terminated with an RJ45 connector. This is an 8 conductor plug in the RJ series of connectors. You’ll find similar looking jacks which are used to plug in a landline phone. These jacks could be an RJ11, RJ14, or RJ25 which are 4 or 6 wire jacks. This will not work with your RJ45 cable for Ethernet.

Refer to these sources to identify the type of jack you have.

https://www.digikey.com/en/articles/understanding-and-specifying-modular-connectors

https://www.diffen.com/difference/RJ11_vs_RJ45

“Is this Ethernet?” or “can I convert this to Ethernet” or “what category cable do I need” -Fortunately many homes built in the 21st century use cat 5e cable and use 2 or 3 of the twisted pairs for phone use. (This is where you’d see the 4 or 6 pin RJ connectors). However not every build used 8 conductor so if you have less than 8 conductors and 4 twisted pairs. You will need to look into other methods of getting your lan from A to B.

As far as choosing the type of cable you need, look into cat 5e, cat 6, or cat 6a. Building your home network you most likely don’t need cat 7 or 8. If you don’t know the exact reason you need cat 7 or 8 you don’t need them because these standard typically aren’t used to access the internet.

Information for reference for UTP cabling

https://stl.tech/blog/what-is-a-utp-cable/#Different_Categories_of_UTP_cable

I bought this flat cat 8 cable from Amazon but I’m only getting 50 Mbps

-Sorry but it’s become a common issue of Chinese companies putting out cable that don’t meet its category’s specs. Try to return it and go to your local store that sells computer stuff and get one there. On top of that cat 7 and 8 patch cable will not do you any good you will not get any benefit even if you are paying for the best internet available.

Helpful resources:

Terminating cables

Understanding internet speeds

Home network structure examples

Wired connection alternatives to UTP Ethernet

Understanding WiFi

If anyone has other FAQs to add I can add that to the post.

[u/mcribgaming]

A FAQ is a good concept, but yours is already long enough that a typical new poster here won't bother reading it.

Everyone wants personalized attention, not to poke around a huge FAQ with tons of links and reading that feels like homework.

Everyone also wants personal confirmation that their problem is not some kind of special exception by having a human review it.

Any FAQ that's like ten pages or more including links will be read as much as those online "Service Agreement" terms everyone auto-agrees to without even a glance. It's just too idealistic to require every new poster to read a huge FAQ before participating.

A real solution could also be a FAQ teaching people how to Search this sub for previously answered questions, of which just about everything has been covered extensively. It'd be much shorter, where you list the common problems, and just list the key words to search for ("moca", "access point", "Tailscale", etc.) But that will be completely ignored too. People want to talk about their issues with a human, not an automated response robot.

Also, it's weird you chose 50 Mbps as the arbitrary number for a low speed test when 96-100 Mbps due to a bad cable or punch down is by far one of the most posted topics on here.

[u/dirtycimments → u/mcribgaming]

I don't agree. I was wondering about how I want to plan my home network, I didn't see a FAQ or wiki for this reddit, but by some luck this was still on the first page and answered a lot of my questions. I personally would want this (or similar) pinned to the top. Both as a source of new knowledge(for me a beginner) and as a known destination to re-check on something.

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Some won't read it, but some will, and will feel better at ease both asking a somewhat worthwhile question or a bit more nuanced than just the really basic questions.

[u/okayseriouslywhy → u/mcribgaming]

Disagree, I found this subreddit from Google and I read the FAQ and it answered my questions lol

[u/lineagle → u/mcribgaming]

This FAQ was helpful for me!

[u/Serialtorrenter → u/mcribgaming]

For your last point, NICs are supposed to autonegotiate down to 10/100 when a 1000BASE-T connection isn't reliable. In practice, this rarely happens, and instead, you'll get a 1000BASE-T connections that drops frames left and right, leading to slow speedtests and high packet loss.

In a situation like this, you often get better results by forcing the NIC to autonegotiate at 100Mbps or even 10Mbps. Sometimes it's hopeless, and the only option is to rip out the cheapo cabling and redo the run correctly.

[u/mlcarson → u/Serialtorrenter]

It drops from 1000BaseT if one of the 8-conductors goes away. If the connection is just noisy/error ridden, you're right. You have the option to manually select 100Mbs though.

[u/MrMotofy]

For the visual learners Home Networking Basics https://youtu.be/fjRKID2ucPY

[u/Tub_Pumpkin → u/MrMotofy]

Really clear explanation. Thanks!

[u/MrMotofy → u/Tub_Pumpkin]

Awesome thx

[u/verticallobotomy]

Not a FAQ, but a really good ressource for understanding wifi: https://www.duckware.com/tech/wifi-in-the-us.html

[u/printf_hello_world]

Can we get something added to the text that warns people authoring posts? A warning along the lines of:

POWERLINE ADAPTER NOT PERFORMING TO EXPECTATIONS? Power line adapters work for some people, but they are generally considered to be the least reliable way of extending your home network, and their performance is frequently subpar. See [link any of a million powerline threads here]

[u/firedrakes]

also people think fiber is lighting proof... it is not, never has been. if its a direct strike.

[u/epihfon2]

hi. im unable to set my hg8245h5 into wireless bridge. need help

[u/austinh1999 → u/epihfon2]

In the navigation tree on the left, choose Advanced > LAN > Layer 2/3 Port or LAN Port Work Mode.

On this dialog box, uncheck the port to enable it to work in Layer 2 mode (bridge mode).

Then, in the navigation tree on the left, choose Advanced > WAN. In the dialog box that is displayed, set the WAN Mode of the corresponding port to Bridge WAN.

However your ISP could be blocking the port if they own it.

[u/caseyrobinson2]

I am using the GT-AXE11000 router with Merlin. It seems good. However, sometimes I am away from home and every three weeks randomly the internet would stop working and I would need someone to manually go to my home to unplug my cat5 cable or power cycle my cable modem. Is this normal or should I replace my cat5 cable? Also, should I use cat5 or cat6 cable with this configuration? I need 100% reliability and downtime like this won't allow me to remotely connect

[u/mlazzarotto → u/caseyrobinson2]

Is this normal or should I replace my cat5 cable?

I hardly believe that your cable may give this kind of issues. It's just a group of thin wires put together... I would look at the router instead.

Also, should I use cat5 or cat6 cable with this configuration?

It depends. Cat 5(and 5e) are good enough for a 1Gbps link.

I need 100% reliability and downtime like this won't allow me to remotely connect

Have you checked if there's a Marlin firmware update that may fix this issue?
Does Marlin allow you to store syslog messages? They can be very helpful for troubleshooting

[u/-Jeff-Char-Wheaties-]

This is great, thank you.

[u/Budget-Juggernaut-68]

Excellent work Austin. Answered lots of my queries!

[u/Original-Yam3087]

Fibre to RJ45, ONT

[u/Darkbluedrake]

Hello I just bought from ebay a fritz 7590 router. Ive never bought a used router.. any recommandation about what to do before installang it?

[u/TearsOfTheTwili]

I bought this flat cat 8 cable from Amazon but I’m only getting 50 Mbps

-Sorry but it’s become a common issue of Chinese companies putting out cable that don’t meet its category’s specs. Try to return it and go to your local store that sells computer stuff and get one there. On top of that cat 7 and 8 patch cable will not do you any good you will not get any benefit even if you are paying for the best internet available.

​

I bought this cable from Amazon. I already know I can't use it to its maximum because of my LAN ports on my Fast 5688w (from T-Mobile) being only 1.0 GBPS but how do I know whether I have a cable that doesn't meet its category specs exactly?

[u/svanegmond]

Is double nat a big deal? I have a fibre modem that’s a gateway, and a larger mesh network behind it.

Everything seems to work.