[striking]

WebSockets are for fast, low-overhead connections. If you end up making a new HTTP connection for every update, and there are a lot of updates happening, you should be using WebSockets instead.

Otherwise, HTTP works best. It has better tooling and will soon be even faster due to HTTP/2.

[nojvek]

I'm surprised no one mentions xhr streaming, if your pipe is only one way i.e server notifies client, then xhr streaming is quite easy to use and as fast as websockets.

[striking]

I assume most people consider XHR a kind of HTTP request. It is in the name, after all.