The way Facebook does this is pretty interesting. A common method of doing such notifications is to poll a script on the server (using AJAX) on a given interval (perhaps every few seconds), to check if something has happened. However, this can be pretty network intensive, and you often make pointless requests, because nothing has … Read more
1) Why is the WebSockets protocol better? WebSockets is better for situations that involve low-latency communication especially for low latency for client to server messages. For server to client data you can get fairly low latency using long-held connections and chunked transfer. However, this doesn’t help with client to server latency which requires a new … Read more
It’s simpler than I initially thought.. Basically you have a page that does nothing, until the data you want to send is available (say, a new message arrives). Here is a really basic example, which sends a simple string after 2-10 seconds. 1 in 3 chance of returning an error 404 (to show error handling … Read more
In the examples below the client is the browser and the server is the webserver hosting the website. Before you can understand these technologies, you have to understand classic HTTP web traffic first. Regular HTTP: A client requests a webpage from a server. The server calculates the response The server sends the response to the … Read more