What you're referring to is two completely different requirements. VOIP or video streaming don't need database queries. Those data are sequential by nature. You don't need to page them. Also even those types of data are transported in chunks.
The transmission mechanism, the socket, doesn’t care what data traverses it. Whether the incoming data is a stream or chunks is up to how the receiving end wishes to intercept the data until message completion. The receiver can store incoming packets as an array of chunks or pipe the incoming into a buffer. The former allows for more convenient segment inspection while the later allows for immediate execution on message fragments.