How to Cheat at VoIP Security

Chapter 11

Skype Firewall and Network Setup

Solution in this chapter:

■ A Word about Network Address Translation (NAT) and Firewalls

■ What You Need to Know about Configuring Your Network Devices

■ Ports Required for Skype

■ Using Proxy Servers and Skype

■ How to Block Skype in the Enterprise

A Word about Network Address Translation and Firewalls

When the Internet began, the creators didn’t envision the type of growth that we are experiencing today. During the last 10 years, the number of hosts on the Internet increased by more than a factor of 50.¹ In order for each Internet device, or host, to communicate on the Internet, it must have a unique internet protocol (IP) address. The addressing scheme for the Internet allowed for billions of IP addresses, ...