Firewall Policies and VPN Configurations
With in-depth coverage of the top market-leading firewall products, this book focuses on creating policies that apply to multiple products and offers numerous tips for troubleshooting remote connections.
TABLE OF CONTENTS Firewall Policies and VPN Configurations
Chapter 8: Case Study SOHO (Five Computers, Printer, Servers, etc.)
Introduction
The Internet continues to grow as small businesses and home users realize the opportunities available to them with a wider audience for goods. Using personalized Web sites and e-mail addresses, and having a permanent Internet connection create a closer customer experience with remote users. This closeness comes at a price as systems are made accessible 24x7. With accessibility, unwelcome guests and customers have invitations to use the network. The exploitation of vulnerabilities on a system include misusing protocols, or applications, by connecting to an IP address on an open TCP or UDP port of a system on the network. Security for the home isn t as well developed as in a corporate environment. Users often do not have the time to become experts, while maintaining their business or working remotely.
Using netstat to Determine Open Ports on a System
The netstat command does many useful things other than determining open ports on a system, including displaying memory and network buffer usage, system route table information, and interface statistics. To understand more about those options, read the documentation online about netstat. The following focuses on using netstat to determine the open ports and whether they should be open.
When a remote system or user wishes to access a service on your computer (e.g., Web server), the underlying OS on the remote system creates a connection to a port on your computer system on behalf of the remote user.
A process listening on a port will accept incoming connections...
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