I am developing a WebSocket service using NodeJS and Einaros WS module and I have raised this question: NodeJS Einaros WS Connection Timeout which apparently no one know the answer so I presume I should write my own ping pong based system to check whether a client is still connected or not.
I am not sure whether I should write code on server side or client side; I mean if the server should ping the client or... the client (which is my own websocket application) should ping the server.
Is there any difference between both methods ?
It is called a heartbeat and is usually sent by the client every 5 seconds with a ping frame (0x09) as opcode while the server responds with a pong frame (0xA) as opcode.
In theory it doesn't really matter whether it's the server or client initiating the heartbeat, but in a real-world situation it is usually better that the client keep itself updated whether the server is there or not to be able to inform the user as quickly as possible.