Find out if a player has loaded the mod

[SmokingDude]

I'm currently working on a mod for a server and I'd like to make sure that people who connect without the mod is disconnected, but I have no idea how I should do it, the mod will be installed on the server side and will have to be installed on the client side, but how do I know if it is well installed on the client side? 

Edited April 12, 2021 by SmokingDude

[ChampionAsh5357]

Any mod present on the server (assuming it doesn't have the ignore extension point set) must be present on the client to allow both to connect.

Edited April 12, 2021 by ChampionAsh5357
I'm wrong, read dies's explanation

[SmokingDude]

I added a network channel, but how can i know if the channel exist on the client side ?

Edited April 13, 2021 by SmokingDude

[Draco18s]

Create the channel on the server side.

When the client connects, if they don't create that same channel, they cannot connect.

You don't have to do anything besides create the channel.

[SmokingDude]

private static final String PROTOCOL_VERSION = "1.0";

public static final SimpleChannel INSTANCE = NetworkRegistry.newSimpleChannel(

    new ResourceLocation("cosmod", "main"),

    () -> PROTOCOL_VERSION,

    PROTOCOL_VERSION::equals,

    PROTOCOL_VERSION::equals

);

I actually have this in a class i don't have to specify i register the simpleimpl anywhere ? 

[SmokingDude]

Perfect that work thank you really much diesieben07 thank you too Draco18s and championash5357 for tried to help