2. TCP/IP Overview

2.1 Introduction

The flow and routing of data on the Internet is controlled by a set of protocols called the Transmission Control Protocol/Internet Protocol (TCP/IP) suite. These protocols provide many sorts of services. Some protocols provide a connectionless, best-effort, datagram delivery service. Others provide a connection-based reliable data delivery service. Still others provide routing, name resolution, and network control messaging. Together, the TCP/IP protocols form an infrastructure that applications can use to communicate with peer applications on machines across the room or across the world.

Before beginning our examination of the role of tunnels and VPNs in networking, let’s review some of the basic facts ...

Get VPNs Illustrated: Tunnels, VPNs, and IPsec now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.