Useful Tools & Information
- My IP Address
See what source IP address your outbound connections are coming from along with a wealth of other information sent by your browser
- IP Precedence, TOS & DSCP
An explanation of the many and various uses and interpretations of the TOS field in the IP header
- Fibre Distance Limits
Limits for various flavours of Ethernet (and ATM) and types of fibre
- IPv6 Addressing
An amusing analysis of exactly how large the IPv6 address space really is and how it is allocated
- Multicast Addressing
An explanation of how IP and Ethernet multicast addresses are related. Includes a converter tool to convert between them (if you couldn't be bothered reading the explanation !!)
- IP Multicast Test Utility
A Windows tool for testing IP multicast in your network
- OpenSSL Cheat Sheet
Quick-reference sheet of useful OpenSSL recipies for converting X.509 digital certificates between different formats
- X.509 Certificate Decoder
A Java applet for decoding X.509 digital certificates and displaying their contents
- Debugging Cisco PIX High CPU Utilisation
A short explanation of how to determine which process on your PIX is gone nuts and a Perl script to make it easier to do
- Cloning a Linux Machine from Backups (pdf)
Brief instructions for cloning a Linux machine from backups taken using the standard dump utility
- PIX/ASA version 7 VPNs (pdf)
Some configuration information about new IPSec VPN features in PIX/ASA version 7. In particular, this document shows how to configure per-group ACLs (without having to using the ACL on the outside interface)
- VLAN Hopping
An article looking at the myths and realities surrounding the security of switched VLANs
- Password Generator
A utility for generating properly-random passphrases for WEP/WPA, IPSec etc.
- Decode Cisco Password:
This only works for "type 7" passwords. "Type 5" password can't be decrypted. The decryption is done in your browser. The password isn't transmitted anywhere.