Hi guys I was just wondering if the websocket protocol already handles the sending of large data in chunks. At least knowing that it does will save me the time of doing so myself.
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I was just wondering if the websocket protocol already handles the sending of large data in chunks...
Depends what you mean by that.
The WebSockets protocol is frame based (not stream based)
If what you're wondering about is "will a huge payload arrive in one piece?" - the answer is always "yes".
The WebSockets protocol is a frame / message based protocol - not a streaming protocol. Which means that the protocols wraps and unwraps messages in a way that's designed to grantee message ordering and integrity. A messages will not get...
...truncated in the middle (unlike TCP/IP, which is a streaming based protocol, where ordering is preserved, but not message boundaries).
The WebSockets protocol MAY use fragmented "packets"
According to the standard, the protocol may break large messages to smaller chunks. It doesn't have too.
There's a 32 bit compatibility concern that makes some clients / servers fragment messages into smaller fragments and later put them back together on the receiving end (before the onmessage callback is called).
Application layer "chunking" is required for multiplexing
Sending large payloads over a single WebSocket connection will cause a pipelining issue, where other messages will have to wait until the huge payload is sent, received and (if required) re-assembled.
In practice, this means that large payloads should be fragmented by the application layer. This "chunked" application layer approach will enable multiplexing the single WebSocket connection.
Myst
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According to RFC-6455 base framing, has a maximum size limit of 2^63 bytes which means it actually depends on your client library implementation.
Behdad
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