TCP vs UDP

TCP - Transmission Control Protocol =>   connection based, flow-control , error checking , in order delivery, guaranteed delivery, relatively slower ( FTP, HTTP/HTTPS, SSH, POP/IMAP, SMTP, DNS ) 

UDP - User Datagram Protocol - connection less, no flow control , no error checking , packet loss possible and they can be out of order, faster ( VPN tunneling , video streaming, online games, live broadcasting, DNS, VOIP, TFTP ) 


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