Many people now connect to the internet over Wi-Fi, but wireless connections have a real downside: the signal can be unstable.
A wired connection using an Ethernet cable, by contrast, tends to be faster and more stable, and it is also relatively more secure.
A wired connection depends on having an Ethernet jack, sometimes called a LAN outlet, and as the number of devices people want to connect to the internet keeps growing, plenty of people find themselves short of available jacks.
This article covers the basics of the Ethernet jack, how to install a new one or add an extra one, and the precautions to keep in mind when doing this kind of work in a rental unit.
If you find yourself wishing you had "just one more Ethernet jack," we hope this proves useful. Readers in the United States or the United Kingdom, where most rental units are wired for a phone jack or nothing at all and residents lean almost entirely on Wi-Fi routers, may find some of what follows unfamiliar, since built-in Ethernet wiring is far more of a default feature in Japanese apartments than in most Anglo-American rental housing.
What Is an Ethernet Jack?
For readers who are not familiar with the Ethernet jack, this section explains the basics.
It also covers how internet connectivity in rental housing tends to be set up in Japan, so it is worth a look.
The Basics of the Ethernet Jack
An Ethernet jack is the socket where an Ethernet cable plugs in, used to connect a computer or other electronic device to the internet by wire.
It is usually installed on a wall alongside a power outlet, and depending on the location it may also be paired with a television antenna socket or the modular jack used for a telephone line.
The Ethernet jack and the telephone's modular jack look quite similar in shape, but the Ethernet jack is easy to tell apart because it is labeled "LAN" near the top.
The Ethernet jack is also sometimes called a "LAN jack."
The Ethernet Jack Is the Standard in Japanese Rental Housing
Besides an Ethernet cable, another way to make a wired internet connection is with fiber-optic cable.
Fiber-optic service is now the norm for detached houses in Japan, so newly built homes often come with a fiber-optic socket already installed for that connection.
In Japanese rental apartment buildings, however, a fiber-optic socket is rarely provided as standard, and an "Ethernet jack" is installed instead in most cases.
Even in a building where fiber-optic service has been brought in, if the building uses a LAN-distribution wiring method, residents still connect to the internet through an Ethernet jack. Anyone moving from a house in the United States or the United Kingdom, where a coaxial cable outlet for a cable modem is the more typical default, should expect the Japanese apartment norm to look somewhat different.
The Difference from "Outlet LAN"
Next, this section explains "outlet LAN" (power-line networking), a technology that is often confused with the Ethernet jack.
What Is Outlet LAN?
Whether someone calls it a "LAN outlet" or a "LAN jack," both terms refer to the same thing: the socket where an Ethernet cable plugs in.
What is often confused with this, despite meaning something completely different, is "outlet LAN."
"Outlet LAN" refers to a technology that uses a building's electrical wiring itself as the internet communication line.
This technology is also called "PLC," for power-line communication, and as long as two outlets draw power from the same distribution board, plugging an adapter into either one can establish an internet connection between them.
In a detached house, this can turn every outlet in the home into a wired internet connection point, and in an apartment building it can, in principle, do the same for the outlets in every unit.
The Advantages and Disadvantages of Outlet LAN (Power-Line Networking)
Many people think of internet connectivity as a choice between only two options: a wired connection using an Ethernet cable, or a wireless connection over Wi-Fi.
In reality, though, there is a third option.
That option is the power-line communication technology introduced above, "outlet LAN," or PLC.
Outlet LAN has the advantage of working in places where running an Ethernet cable is difficult or where a Wi-Fi signal has trouble reaching.
Another appeal of outlet LAN is that it does not require any complicated construction work.
That said, its communication speed is only about a half to a quarter of what a wired Ethernet connection can achieve, which is fine for sending email or browsing the web but not well suited to business use. American and British readers who have tried "powerline adapters" sold for exactly this purpose, often under brand names built around the same PLC standard, will recognize both the convenience and the same speed trade-off described here.
The Shape and Standards of the Ethernet Jack
If you are considering installing a new Ethernet jack or adding one, it is worth understanding its shape and the standards involved.
Here are the shape and the standards of the Ethernet jack.
There Is Only One Shape of Ethernet Jack, but the Standards Differ
If you lift the little tab on an Ethernet jack, you will see eight metal pins.
This shape is called "RJ-45," and every Ethernet jack installed in an ordinary household in Japan uses this same RJ-45 shape.
In the same way, the connector on an Ethernet cable is also standardized as RJ-45, so an Ethernet cable will never fail to fit an Ethernet jack because the shapes do not match. This is exactly the same RJ-45 connector used throughout the United States, the United Kingdom, and essentially every other country, so an Ethernet cable purchased abroad will plug in without any issue.
That said, the standard supported can differ depending on the speed it is built for, so this is worth paying attention to.
To get the full speed your internet connection is capable of, be sure to connect equipment that matches the relevant standard.
How to Check Which Standard an Ethernet Jack Supports
To check which standard an Ethernet jack supports, look for text reading "CAT" followed by a number, printed near the socket.
This "CAT" number indicates the category of Ethernet cable the jack is built to support.
Refer to the table below for the Ethernet cable categories and the corresponding Ethernet jack standards.
For example, an Ethernet jack labeled "CAT6A" supports speeds up to 10 Gbps, while one labeled "CAT6" supports speeds up to 1 Gbps.
How to Check Which Standard a LAN Port Supports
The socket on the device side that pairs with an Ethernet jack, where the Ethernet cable plugs into the device itself, is called a "LAN port."
To find out which standard a LAN port supports, check the product's specification sheet.
On a computer, you can also check by going to Control Panel, then Device Manager, then Network Adapters, in that order.
On other electronics such as televisions or printers, you may find text near the LAN port reading "LAN (X/X)."
For example, if it reads "LAN (10/100)," the supported standards are 10BASE-T or 100BASE-TX, meaning it supports speeds of 10 to 100 Mbps.
Can You Add an Ethernet Jack by Yourself?
If the number of devices you want connected to the internet has grown and you have run out of Ethernet jacks, you may wonder whether you can add one yourself rather than hiring someone.
This section explains whether it is realistic to add an Ethernet jack on your own, without relying on a contractor.
Running the Ethernet Cable Itself Is Relatively Easy
The short answer is that even a beginner can add an Ethernet jack on their own.
Work that involves handling 100 to 200 volts of electricity normally requires an electrician's license, but the current flowing through an Ethernet cable is far lower, so no special license is required for it.
As for running the Ethernet cable itself, as long as you prepare a cable of the right length and shape, the job is relatively straightforward.
No license is required for installing the Ethernet jack either.
That said, unlike simply running the cable, installing the jack itself calls for a certain amount of hands-on skill.
Installing the Ethernet Jack Itself Is Difficult for Beginners
The part of installing an Ethernet jack that most requires skill is what is called "in-wall wiring," running the cable through the conduit inside the wall.
Before doing in-wall wiring, you first need to check whether a CD conduit, a flexible plastic conduit used for wiring, exists inside the wall, which you can confirm by removing the outlet cover.
Once you have confirmed the CD conduit is there, you use a fish tape to feed the Ethernet cable through the conduit, but if the cable's length or type does not match, it can jam inside the conduit and bring the work to a halt.
And if there is no CD conduit at all to begin with, it is simply not possible to run wiring inside the wall safely.
If an untrained person attempts in-wall wiring without any preparation or background knowledge, there is a real risk, in the worst case, of damaging the building itself, so be sure to fully understand the necessary tools and steps before starting the work.
Anyone who feels uneasy doing this kind of work alone should consider hiring a professional. Renters in the United States and the United Kingdom face the same basic barrier: fishing a cable through a finished wall is exactly the kind of work that voids a security deposit if it goes wrong, which is why professional low-voltage cabling contractors exist there as well.
How to Install an Ethernet Jack, Step by Step
As explained above, installing an Ethernet jack does call for a certain amount of skill, but that does not mean doing it yourself is impossible.
This section walks through the process in detail for anyone who has decided to do the installation themselves.
What You Need to Prepare Before Installing an Ethernet Jack
First, gather the tools needed to install an Ethernet jack.
At minimum, you will need the following tools.
A Phillips-head screwdriver and a flat-head screwdriver
Diagonal cutters
A utility knife
A cable tester for Ethernet cable
A cable tester, sometimes called a "LAN checker," is a device used to check for broken wires or wiring mistakes.
Not essential, but handy to have, is a crimping tool made for cable connections.
It typically combines diagonal cutters, a knife, and a stripper for removing the cable's outer sheath into a single tool, so you do not need to buy each one separately.
Also, if you want to seat the wire firmly all the way into the slot on the Ethernet jack, a tool called a punch-down tool is useful.
There Are Three Ways to Add an Ethernet Jack
There are three approaches to adding an Ethernet jack.
1. Add a standalone Ethernet jack
2. Add one to an existing power outlet
3. Add one using a switching hub
The sections below mainly cover methods 1 and 2 in detail.
Adding a Standalone Ethernet Jack
To add a standalone Ethernet jack, you use a plate made up of only the Ethernet jack itself, and proceed through the following steps.
1. Turn off the breaker and disconnect the Ethernet cable from the device
Remove the outlet cover and the mounting frame.
Insert a fingernail or a flat-head screwdriver into the gap between the wall and the outlet cover to remove the cover, then loosen the mounting frame's screws with a Phillips-head screwdriver and remove the mounting frame as well.
2. Strip the sheath from the end of the Ethernet cable
Cut off the connector already attached to the end of the Ethernet cable, then, taking care not to nick the internal wires, strip about three centimeters of sheath from the tip.
Next, use the diagonal cutters to cut away the small plastic cross-shaped spacer at the center of the four wire pairs.
3. Secure the wires to the Ethernet jack
The eight wires are grouped into four color-coded pairs, so fix each wire into its slot according to the labeling on the jack.
At this stage, try to keep the twist in each pair intact as close to the jack as possible, since this helps with noise resistance.
Use a punch-down tool or similar to make sure each wire is seated firmly all the way into its slot.
4. Trim the excess wire and close the cover
Trim any excess wire as short as possible and close the cover.
5. Mount the Ethernet jack on the wall
Fit the Ethernet jack into the mounting frame, then attach it to the wall.
Be careful not to get the orientation upside down.
6. Attach the outlet cover
Reattach the outlet cover to the wall as it was before, and the work is complete.
Adding One to an Existing Power Outlet
Next is how to add an Ethernet jack to an existing power outlet.
1. Turn off the breaker and disconnect the Ethernet cable from the device
2. Remove the outlet cover and mounting frame from the wall
Insert a fingernail or a flat-head screwdriver into the gap between the wall and the outlet cover to remove the cover, then loosen the mounting frame's screws with a Phillips-head screwdriver and remove the mounting frame as well.
3. Feed a fish tape through the conduit
Once you have confirmed there is a CD conduit inside the wall, insert the fish tape and pull it through once it becomes visible at the conduit opening on the other side.
4. Use the fish tape to pull the Ethernet cable through the conduit
Tie the Ethernet cable to the tip of the fish tape you pulled out, then pull the fish tape back from the other side to draw the Ethernet cable through the conduit.
Tape the fish tape and the Ethernet cable together securely along the way so they do not come apart partway through.
If the cable is hard to pull through, do not force it; instead, use a lubricant or make small adjustments to work it through.
5. Process the end of the cable and attach it to the mounting frame
Process the end of the cable and attach it to the mounting frame using the same method as when adding a standalone Ethernet jack.
6. Attach the mounting frame and outlet cover to the wall
7. Once the mounting frame and outlet cover are attached to the wall, the work is complete
Substituting a Switching Hub
If a rental unit does not allow drilling holes in the wall, you can also substitute a switching hub for an Ethernet jack.
However, if you want to distribute the connection to a different room, you will need a long Ethernet cable, and the exposed wiring tends to stand out.
In that case, it is a good idea to run the cable as close to the wall as possible, or hide it inside cable molding.
Precautions When Adding an Ethernet Jack in a Rental Unit
People living in rental housing sometimes want to add an Ethernet jack.
In that situation, there are precautions that differ from what applies in a detached house that you own, so it is important to understand them.
Let us look at the specific precautions involved.
Do Not Add One Without Permission
Adding an Ethernet jack without permission in an apartment or similar multi-unit rental building is very likely to cause trouble later on.
For that reason, always check with the management company or the owner before adding one.
Any addition that requires drilling a hole in the wall can potentially develop into a claim for damages.
That said, because adding an Ethernet jack rarely involves the kind of work that carries a fire risk, unlike adding a power outlet, many management companies and owners are willing to grant permission.
The real problem arises specifically when the work is done without permission in the first place.
This rule applies not only to apartments and rented condominium units but also to owner-occupied condominiums. This permission requirement will feel familiar to American and British tenants too: most standard leases in the United States and the United Kingdom likewise require written landlord consent before a tenant drills into a wall, and doing so without permission is treated the same way it is in Japan, as a matter that can be charged against the security deposit.
The Building's Structure Can Make Adding One Difficult
Some properties use concrete for their wall material.
In that case, doing the work yourself becomes more difficult.
If you hire a contractor, drilling into concrete is more technically demanding, which tends to push up the labor cost.
Also, if there is no CD conduit inside the wall for running the Ethernet cable, one will need to be newly installed.
All of this raises the bar for adding an Ethernet jack.
If the labor cost goes over budget, you may end up having to give up on adding an Ethernet jack altogether.
That said, if adding one proves too difficult, running the cable along the surface is another option worth considering.
This means making use of something like a switching hub.
Options include securing the Ethernet cable along the wall with double-sided tape or hooks, or hiding it inside cable molding to make it less noticeable.
Keep in mind that hiding the cable with molding can, in a rental unit, trigger an obligation to restore the property to its original condition when you move out. This "restoration to original condition" obligation, called genko kaifuku in Japanese, does not have a single clean equivalent in the United States or the United Kingdom, but it functions much like an expanded version of normal wear-and-tear rules governing security deposit deductions, except that Japanese practice tends to hold tenants responsible for a somewhat broader range of alterations than "normal wear and tear" typically covers under an American or British lease.
Pay Attention to the Length and Standard of the Ethernet Cable
When adding an Ethernet jack, pay attention to the length and standard of the Ethernet cable.
If you do not check this carefully in advance, you can run into trouble such as the cable turning out to be too short, or the cable's category not matching your internet connection.
If that happens, you will face the extra time and cost of redoing the DIY work or buying a replacement cable.
It is safest to check things such as how long a cable you will need at the location where you plan to add the jack, and what speed your internet contract provides, before buying what you need.
Work Carefully and Deliberately
Adding an Ethernet jack requires work such as drilling a hole in the wall and removing the existing plate.
If you get the location or size of the hole wrong, you will need repairs, which means extra work.
In a rental unit, you are quite likely to be billed for the repair cost.
It is also not unusual for the existing plate to have deteriorated over time.
If it has, forcing it off can cause it to crack, so you need to work with great care.
Beyond that, mistakes such as dropping a tool or a part while working with a hole open in the wall are also fairly common, so make sure to carry out the work carefully and deliberately.
How Much Does Installing or Adding an Ethernet Jack Cost?
Many people choose to hire a contractor for installing or adding an Ethernet jack rather than doing it themselves.
Naturally, some people want to know roughly how much a contractor would charge.
The next section explains the cost of installing or adding an Ethernet jack.
The Cost of Adding an Ethernet Jack to an Existing Outlet
Adding an Ethernet jack to an existing outlet typically costs in the range of ten thousand to fifty thousand yen.
Because the work can reuse the existing wiring and circuit, and does not require drilling a new hole in the wall, the cost stays relatively low.
The two factors that most affect the cost of installing an Ethernet jack are the distance from the point where the wiring is brought in, and the type of Ethernet cable used.
The cost rises if the wiring distance is longer, or if you choose a higher-performance cable such as Category 5e or Category 6.
The Cost of Installing or Adding an Ethernet Jack on a Different Floor
Installing a new Ethernet jack on a different floor requires running new conduit from scratch, so it typically costs in the range of forty thousand to a hundred thousand yen.
Adding one, on the other hand, can be done for roughly ten thousand to fifty thousand yen if conduit already exists.
This is possible because the connection can be pulled from the existing conduit.
As with adding a jack to an existing outlet, the cost also varies considerably depending on the wiring distance and the type of Ethernet cable.
If you want an accurate quote, it is worth telling the contractor you plan to hire that you would like as precise a quote as possible.
Other Ways to Add More LAN Ports Besides Installing or Adding an Ethernet Jack
There are ways to increase the number of LAN ports besides installing a new Ethernet jack or adding one.
The next section highlights a few other ways to add more LAN ports.
If you are looking to increase your LAN ports without installing or adding an Ethernet jack, we hope this is useful.
Set Up a Hub
If you want more places to plug in Ethernet cables, setting up a hub, a switching hub, can achieve this.
A hub is a device that lets multiple devices connect to each other over a local network.
If all you are doing is connecting a hub, no construction work is needed.
That said, a hub cannot bridge a room that is far away or span floors, such as connecting the first floor to the second, so keep this in mind.
The only cost involved in setting up a hub is the price of the hub itself.
The price varies with the hub's performance, ranging from around fifteen hundred to two thousand yen for an inexpensive one, up to around twenty thousand yen for a high-performance model.
Because the standard and the number of ports differ from hub to hub, be sure to choose a product suited to your needs. A basic unmanaged switch of this kind is sold everywhere in the United States and the United Kingdom too, usually under the plain label "Ethernet switch," at broadly comparable prices.
Set Up Outlet LAN (PLC)
Outlet LAN, or PLC, is a communication technology that runs over the building's electrical wiring.
Using it turns a power outlet into a substitute for an Ethernet cable.
This means you can get internet connectivity without installing or adding any new Ethernet wiring.
It is a good option for a room that is far from an Ethernet jack, or one where the Wi-Fi signal has trouble reaching.
That said, keep in mind that outlet LAN, PLC, also has downsides: it often tops out at 100 Mbps or below, and it tends to be vulnerable to electrical noise, which can make the connection unstable.
Setting up outlet LAN, PLC, typically costs in the range of five thousand to thirty thousand yen.
The cost of setting up outlet LAN varies with the adapter used.
The more expensive the adapter, the better its speed and stability tend to be.
It can hold down costs compared with running new Ethernet wiring, but whether the connection speed satisfies you will depend on how you plan to use it.
Switch to Wi-Fi
If the number of devices you want to connect to the internet has grown, switching to Wi-Fi is also worth considering.
Installing or adding an Ethernet jack costs money and takes effort.
Also, the more wiring you add, the more cluttered the cables can become.
That can leave a room looking messy, so it is worth considering a switch to Wi-Fi.
With Wi-Fi, you can add more connected devices without worrying about their physical layout.
Another major advantage is that, as long as you are within range of the signal, you can connect from anywhere.
That said, Wi-Fi does tend to be less stable and slower than a wired Ethernet connection.
Using wired and wireless connections together, depending on the situation, can resolve most sources of dissatisfaction.
For Speed and Stability, a Fiber-Optic Socket Is Recommended
If internet speed and stability matter to you, it is also worth considering a fiber-optic socket.
This is a socket built for a fiber-optic connection.
If a fiber-optic socket is not already installed, you will need to have one installed before you can use fiber-optic service.
Finally, this section explains in detail what a fiber-optic socket actually is.
About the Fiber-Optic Socket
A fiber-optic socket is the connection point used to link a fiber-optic cable to an ONU, an optical network unit that terminates the fiber-optic line.
Fiber-optic cable is brought in from a utility pole, and the fiber-optic socket is installed inside the home.
Once you connect the ONU installed in the room to this socket with a cable, you are able to use the fiber-optic connection.
It is typically labeled "hikari" or "hikari concent SC," so you can quickly identify it just by looking at the wall.
Fiber-optic service differs by provider, so switching providers can sometimes require the installation work to be redone.
The Difference from an Ethernet Jack or a Modular Jack
Besides the fiber-optic socket, there are other ways to access the internet, including the Ethernet jack and the modular jack.
Let us confirm what exactly the Ethernet jack and the modular jack are.
Ethernet jack
An Ethernet jack is a method that runs an Ethernet cable from the fiber-optic line already brought as far as a building's shared areas into each individual unit.
The socket is labeled "LAN," and you use it simply by plugging in a cable.
Because it works simply by plugging in, it is quite convenient.
However, its connection speed is inferior to that of a fiber-optic socket.
It is also worth knowing that using other electronics at the same time can further reduce the connection speed.
Modular jack
A modular jack is a method in which each room has a telephone jack installed, which is then used to connect to the internet.
A dedicated device called a modem is required.
The wiring runs from the building's shared areas over telephone-grade cable, and the wiring is shared across the whole building as a single line.
Because of this, it is not possible to switch just one room over to a fiber-optic socket on its own.
Speeds are slow, so if you try to stream video or make online calls, the load on the line can make things run poorly.
There Are Two Types of Fiber-Optic Socket: Integrated and Separate
It is also worth knowing that fiber-optic sockets come in two types, integrated and separate.
Integrated type
The integrated type combines the fiber-optic socket with the coaxial socket used for electricity and television, and with the Ethernet jack, all in one unit.
The fiber-optic socket is positioned on either the left or right side of the plate.
As the number of sockets on the plate increases, the plate itself takes up more area.
Plates come in three patterns, single, double, and triple, and the more sockets a plate has, the more socket types it tends to include.
If you are planning to install an integrated fiber-optic socket, think carefully about what other sockets would be convenient to have alongside it before deciding.
The integrated type is also difficult to install later, so anyone living in a rental unit should check for one before moving in.
Separate type
With the separate type, the fiber-optic socket is installed apart from the regular outlets.
This type is distinguished by not having any power-outlet-style sockets on its face.
The way the fiber-optic cable is brought in also differs from the integrated type.
With the integrated type, the cable is often installed at the end of the same conduit used for telephone wiring, so the fiber-optic cable runs through that same conduit.
With the separate type, however, the cable is more often brought in without using a conduit at all.
Specific examples include running it through an air-conditioner duct or a window.
Though rare, there are also cases where the cable is brought in directly through a hole drilled in the wall.
The Advantages and Disadvantages of a Fiber-Optic Socket
The advantage of a fiber-optic socket is that, if it is already installed, you can start using the internet as soon as the ONU arrives.
Being able to get your internet connection up and running smoothly is a very appealing benefit.
The disadvantage is that it cannot be used if the fiber-optic provider is different from the one you plan to use.
If the provider is different, the installation work needs to be done all over again.
If you need internet access right away, it is a good idea to check whether a fiber-optic socket is present, and which provider it is set up for, during a property viewing before you move in. American and British apartment shoppers face a version of the same question when checking whether a unit already has fiber or cable service from their preferred provider, though the specific "which provider is this socket wired for" check described here is distinctly tied to how Japanese buildings are wired.
When using the internet at home, people sometimes consider installing or adding an Ethernet jack to improve convenience.
If you own your home, you can do whatever you like, but a rental unit is a different story.
You need to check with the management company or the owner before doing any work.
If installing or adding an Ethernet jack turns out to be difficult, it is worth knowing the other ways to add LAN ports besides installing or adding an Ethernet jack, since this can improve your quality of life.
Choosing a property that already has a fiber-optic socket installed is another option to keep in mind.
