Part IV consists of the following summary appendices:

Appendix A, Resources , contains a list of places you can go for further information and help with Internet security -- World Wide Web pages, FTP sites, mailing lists, newsgroups, response teams, books, papers, and conferences.

Appendix B, Tools , summarizes the best freely available Internet security tools and how you can get them.

Appendix C, TCP/IP Fundamentals , contains background information on TCP./IP that is essential for anyone who is building or managing a firewall. This appendix is excerpted from Craig Hunt's excellent book, TCP/IP System Administration.