What Is MoCA? How to Use Coax Cable Instead of Ethernet

MoCA is a way to send your home network over coaxial cable, the round screw-on cable installed for cable TV. If your house has coax outlets in the rooms where Wi-Fi is weak, a pair of MoCA adapters can turn that cable into a wired network link at up to 2.5 Gbps, with no new cable to run.

MoCA stands for Multimedia over Coax Alliance, the industry group that writes the specification and certifies products. This is a research-based guide. It draws on the alliance’s published specifications and on documentation from two adapter makers. We have not tested MoCA adapters ourselves, and the speed figures are specification and manufacturer claims.

How does MoCA work?

A MoCA adapter is a small box with a coax connector and an Ethernet port. One adapter sits next to your router, connected to it by Ethernet and to the wall by coax. A second adapter sits in another room, connected to that room’s coax outlet. The two adapters find each other over the coax in the walls and behave like a long Ethernet cable between the two rooms.

The reason this can share a cable with other services is frequency. Different signals travel on the same coax at different frequencies, the way radio stations share the air. The MoCA Alliance gives the technology’s overall operating range as 400 MHz to 1,675 MHz. Adapter maker goCoax says its MoCA 2.5 adapter works in the 1,125 to 1,675 MHz band, and describes cable internet’s typical upper limit as 1,002 MHz. MoCA sits above it.

To your router and devices, a MoCA link looks like Ethernet. There are no network names or Wi-Fi passwords involved.

How fast is MoCA?

The MoCA Alliance describes both figures as “actual data rates.” MoCA 2.5 is “backward interoperable with MoCA 2.0 and MoCA 1.1,” so mixed equipment will connect. Expect a link that involves an older device to run at the older device’s speed.

Three things decide what you get in practice:

• The adapter’s Ethernet port. A MoCA 2.5 adapter with a 1 Gbps Ethernet port can’t deliver more than 1 Gbps to the device plugged into it. For multi-gigabit speeds, look for a 2.5 Gbps Ethernet port. The goCoax MA2500D, for example, lists one 2.5GbE port.
• Shared capacity. Adapters on the same coax share one network, so heavy use in two rooms at once generally divides what is available.
• The coax itself. Old splitters, damaged cable and long runs reduce performance. We have no measured figures for how much, so treat 2.5 Gbps as a ceiling and not a promise.

For most homes this is academic. A plan of 1 Gbps or less fits comfortably inside a MoCA 2.5 link. See how much internet speed you need if you are sizing a plan.

Will MoCA work in my home?

Check four things before buying. If you have no usable coax, see whether powerline adapters are worth it instead.

The MoCA Alliance says the technology is “designed to co-exist with legacy services such as TV, DOCSIS, and cellular (4G/5G) technologies.” DOCSIS is the technology cable internet providers use.

If your internet arrives by fiber or a 5G gateway and the coax in your walls carries nothing, MoCA is the simplest case: the cable is yours to use.

Splitters matter too. MoCA signals reach 1,675 MHz, so every splitter between your adapters has to pass frequencies that high. An old splitter rated only to about 1,000 MHz can block or weaken the link. This follows from the frequency range above; check the rating printed on each splitter.

What do I need to buy?

• Two or more MoCA 2.5 adapters. One for the router end, one for each room. Choose adapters with a 2.5 Gbps Ethernet port if any of your equipment has 2.5 Gbps ports.
• A point-of-entry (PoE) filter. Check whether your adapter kit includes one before buying it separately.
• Short Ethernet cables. One per adapter. Our Ethernet cable guide covers which category to use.
• Possibly new splitters, if yours don’t pass MoCA frequencies.

We have left prices out because we only publish a price with the date we checked it.

Why do I need a point-of-entry filter?

Coax leaves your house. Without a filter, MoCA signals can travel back out along the incoming line. Hitron, which makes MoCA adapters, puts it this way: “MoCA filters block MoCA signals from leaking out of the home’s coaxial cabling,” and without one, signals can “interfere with neighboring MoCA networks or cable TV signals.”

The filter is a small barrel-shaped connector. Hitron’s instructions are to install it “at the point where the coaxial cable enters your home,” on the incoming line, ahead of the first splitter.

There is a security reason as well. The MoCA 2.5 specification added “Enhanced Privacy” with longer passwords, and the alliance describes a security feature called MoCASec for link privacy. Even so, a filter is the simple way to keep your network’s signals inside your own walls in the first place. Note that this “PoE” means point of entry. It is unrelated to Power over Ethernet, which shares the abbreviation.

How do I set it up?

1. Fit the PoE filter where the coax enters the home.
2. Connect the first adapter by the router. Coax from the wall to the adapter, Ethernet from the adapter to a LAN port on the router. If a cable modem needs the same wall outlet, use a splitter, or the adapter’s pass-through coax port if it has one.
3. Connect the second adapter in the other room. Coax from the wall to the adapter, Ethernet from the adapter to your device, switch or mesh unit.
4. Wait for the link light. Most adapters have a status light that shows a MoCA connection. If it stays off, the two outlets may not be on the same coax network, or a splitter may be blocking the signal.
5. Set up the security option if your adapters offer one, following the maker’s instructions.
6. Test the speed on a computer wired to the far adapter.

Is MoCA a good way to connect a mesh system?

Yes, where Ethernet isn’t available. A mesh unit connected through a MoCA adapter is using wired backhaul as far as the mesh system is concerned. That takes the unit-to-unit traffic off Wi-Fi, which is the main benefit of cabling a mesh system. Our guide to wired and wireless backhaul explains each brand’s cabling rules, and they apply here too.

If you have Ethernet jacks in the right rooms, use those. If you have coax in the right rooms, MoCA is the next best option. If you have neither, see mesh picks for large houses for systems suited to wireless-only homes.

Fact-check notes

Bottom line

MoCA turns coax you already have into a wired network link. It suits homes with coax outlets in the right rooms and no easy way to run Ethernet. Buy MoCA 2.5 adapters with Ethernet ports that match your equipment, fit a point-of-entry filter, and confirm nothing on that coax is satellite TV. If the link light comes on and a wired speed test looks right, you have the next best thing to Ethernet.