Occasionally we received some feedback about the slow LAN speed from Deco and the typical description would be: "my internet bandwidth is over 200/500m/s, but I only got about 100m/s from Deco". After troubleshooting with different users, the following causes are confirmed to be relevant.
(Note, if the model is Deco E4, you might get the wrong model since Deco E4 is up to 100m/s.)

• The Total bandwidth under QoS is set to be 100/100 m/s.

If you happen to have the same case, please change it to be 1000/1000 m/s.

Visit this guide to configure the QoS settings on the Deco.

• The WAN link speed is capped at 100m/s.

The WAN link speed might be caused by different reasons. The first one would be the Ethernet cable between the modem and main Deco. Please replace it with a good quality Cat5e or Cat6 cable.

If in any case, the issue persists after checking the first two conditions, we need more information to locate the problem:
1. Are all the Deco units capped at 100m/s or just one of the satellite units?
(if it is only one of the satellite units, the troubleshooting guide here might not be helpful, please refer to this link: Why is my satellite Deco unit not getting the same speed as the main Deco?)

2. Please connect a laptop via Ethernet cable to the main Deco and check the link speed on the laptop to verify whether it is 1G or 100m/s.
3. A picture of your network layout, such as

We would love to hear more comments from your experience!

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