An abbreviation for Connection Reset By Peer.

A connection was forcibly closed by a peer. This normally results from a loss of the connection on the remote socket due to a timeout or a restart. On a datastream socket, the connection was reset. This reset could be generated locally by the network system when it detects a connection failure, or it might be received from the remote host (in TCP terms, the remote host sent an RST packet). This error is also possible on a datagram socket; for instance, this error could result if your application sends a UDP datagram to a host, which rejects it by responding with an ICMP Port Unreachable.