What Is a MoCA Adapter, and Is It Better Than Wi-Fi or Powerline?

Many homes in the US have coax outlets in rooms that were wired for cable TV years ago — and no Ethernet anywhere. A MoCA adapter uses that coax to carry a wired network connection from your router to another room, without new cables through walls. For a game console, a TV or a mesh satellite in a far room, it often works better than Wi-Fi. Here is how it works and how to set it up.

What MoCA Is

MoCA stands for Multimedia over Coax Alliance, the industry group behind the standard. A MoCA adapter is a small box with a coax port and an Ethernet port: at one end it puts your network traffic onto the coax cable, at the other end it takes it off and hands it to a device over Ethernet. Verizon describes its MoCA Ethernet Adapter simply as bringing wired Ethernet performance to places like your entertainment center using existing coax.

MoCA uses frequencies on the cable that TV and cable internet do not use, so it can share the same coax with your cable TV and, in many setups, with a cable modem. Many provider gateways and routers already have MoCA built in — Verizon Fios routers, for example — in which case you only need an adapter in the far room.

How Fast MoCA Is

According to the MoCA Alliance, MoCA 2.0 offers actual data rates of up to 1 Gbps, and MoCA 2.5 up to 2.5 Gbps, with latency under 5 ms. That is real throughput, not a marketing link rate, which is why MoCA typically outperforms Wi-Fi and powerline in practice.

Two caveats. First, the bandwidth is shared by all MoCA devices on the same coax network, as Verizon notes, so several adapters streaming at once split it. Second, the network runs at the level of its oldest device: Verizon warns that an older device that does not support MoCA 2.5 can slow overall performance. For most homes, a MoCA 2.5 adapter on a gigabit Ethernet port gives the full speed of a gigabit plan to the far room.

How Many Adapters You Need

MoCA works as a network over your coax, so you need a MoCA device at the router end and one in each room where you want a wired connection:

• If your router or gateway has MoCA built in (common with Fios and some cable gateways), you need just one adapter, in the far room. Verizon’s FAQ says you only need to connect one MoCA Ethernet Adapter to its coax network.
• If your router has no MoCA, buy adapters in a pair: one next to the router, connected to it by Ethernet and to a coax outlet, and one in the far room.

Each extra room needs one more adapter. Verizon’s network supports up to 16 nodes, including the router. Some adapters have several Ethernet ports — Verizon’s has four gigabit ports — so one adapter can serve a TV, a console and a streaming box in the same room.

How to Set It Up

1. At the router: connect a coax outlet near the router to the adapter’s coax port (or the “coax in” port), and the adapter’s Ethernet port to a LAN port on the router. If a cable modem uses the same outlet, connect the wall cable to the adapter and the modem to the adapter’s coax-out (TV/modem) port, if it has one.
2. In the far room: connect that room’s coax outlet to the second adapter, and the adapter’s Ethernet port to your device or to a mesh satellite.
3. Power both adapters on and wait for the link light. Most adapters pair automatically; some have a pairing or encryption button to press on both.
4. Test with a speed test on the device in the far room.

If you have cable internet and the coax line leaves your home, a PoE filter (point-of-entry filter) installed where the cable enters keeps your MoCA signal inside and blocks your neighbors’ signals. Many MoCA adapter kits include one; your provider may already have installed it. For satellite TV, check compatibility first — Verizon notes that its adapter does not support satellite TV devices or satellite-based home networks.

MoCA vs Powerline, Mesh and Ethernet

If the room has a coax outlet, MoCA is usually the best option after a real Ethernet cable. A popular setup is to use MoCA as the wired backhaul for a mesh system: the satellite in the far room connects to the router through coax instead of over the air. See what is mesh Wi-Fi, what is a powerline adapter and Ethernet vs Wi-Fi.

Common Problems

No link between the adapters. Make sure both outlets are on the same coax network — sometimes an outlet is not connected anywhere, or goes through an amplifier that blocks MoCA frequencies.

Slow speeds. Old or cheap coax splitters are the usual cause. Splitters should be rated for the MoCA range (up to 1675 MHz); Verizon’s troubleshooting starts with checking for faulty or outdated splitters and connections. Also check whether other devices on the coax network are using bandwidth.

Cable modem stops working after adding MoCA. Connect the modem through the adapter’s coax-out port, or check that the PoE filter is installed on the line coming into the home, not between the modem and the outlet.

Only 100 Mbps. Check the Ethernet cable and the device’s port; see Ethernet cable not working.