Network services
HTTP keep-alive
Several HTTP requests over one TCP connection instead of a new handshake for each.
HTTP/1.1 keeps the connection open after a response by default, so the next request skips the TCP handshake (and,
over HTTPS, the TLS one). The client finds where each response ends from its Content-Length (or chunked encoding).
Connection: close asks the server to hang up after answering, as HTTP/1.0 did: one handshake per request. The server
closes idle connections after a timeout.