объединение и перенаправление сокетов (Concatenate and redirect sockets)
CONNECT MODE AND LISTEN MODE
Ncat operates in one of two primary modes: connect mode and
listen mode. Other modes, such as the HTTP proxy server, act as
special cases of these two. In connect mode, Ncat works as a
client. In listen mode it is a server.
In connect mode, the hostname and port arguments tell what to
connect to. hostname is required, and may be a hostname or IP
address. If port is supplied, it must be a decimal port number.
If omitted, it defaults to 31337.
In listen mode, hostname and port control the address the server
will bind to. Both arguments are optional in listen mode. If
hostname is omitted, it defaults to listening on all available
addresses over IPv4 and IPv6. If port is omitted, it defaults to
31337.
