OverviewIn the previous article titled Why TCP needs 3 handshakes simple answers were provided to the following three questions:Can application data be carried during the first handshake?Can application data be carried during the second handshake?Can application data be carried during the third handshake?Briefly, traditional TCP requires a three-way handshake to establish a connection, and during these three handshakes, only simple SYN and ACK packets are sent.From the perspective of utilizing network bandwidth resources, the TCP header at the transport layer plus the IP header at the net...

Prerequisite KnowledgeFirst, let's look at the control bits and state machine of TCP, which form the basis for understanding the three-way handshake of TCP.TCP Packet Control BitsThe control bits in the TCP packet header are used to control the status of the TCP connection and can indicate various control information such as connection establishment, termination, reset, etc.There are six common control bits:SYN (Synchronize Sequence Numbers): Requests to establish a connection (part of the three-way handshake). It is set in the initial packet during connection establishment, indicating that th...

IntroductionHi, I’m Glenn Fiedler and welcome to the first article in my online book Networking for Game ProgrammersIn this article we start with the most basic aspect of network programming, sending and receiving data over the network. This is just the beginning – the simplest and most basic part of what network programmers do, but still it is quite intricate and non-obvious as to what the best course of action is. Take care because if you get this part wrong it will have terrible effects on your multiplayer game!You have most likely heard of sockets, and are probably aware that...