Summary
DNS is a protocol used to resolve website names to an IP address. Through DNS, your machine is able communicate on an IP-based network.
FTP has been used to transfer files from one machine to another since the internet came into existence and is still being used in today's modern networks.
Web browsers present and transfer web-based content back and forth using HTTP. It is also commonly referred to as the request/response model, where a host requests a certain resource and the server responds with a status code and the resource if available.
SMTP is very commonly used to send emails. The SMTP command and its corresponding arguments are passed over the wire in plaintext.
VoIP traffic is made up of two things: RTP for data transfer and SIP for session creation. The signaling protocol creates and manages a session where RTP is used to carry the voice itself.
