Frank4DD, @2005-2007
Introduction
When I managed our suppliers remote network support connections, development of complex VPN, firewall and NAT setups were required. Centralized VPN concentrators plus small site-to-site VPN devices of mixed origins had to be supported and configuration knowledge to be exchanged. The most common VPN devices were Cisco's smallest PIX 501 and Cisco 831, together with Linux.
Frank4DD, @2005-2007
Remote VPN Networking with Cisco PIX Firewalls
Cisco's smallest security appliance PIX 501 is a solid device for building site-to-site IPSEC VPN tunnels with speeds of more then 3 MB/s. Although surpassed by Netscreens 5 series in terms of features and flexibility, it handles standard setups easily. Here we describe a site-to-site VPN tunnel setup with Linux. Although there are some setup descriptions on the net, none covered the secific setup for using NAT on the internal interface, to allow only inbound connections from the Internet to the 'inside' network.
- Setting up a 3DES VPN between Linux FreeSwan and a Cisco PIX 501 together with source or destination network address translation [read article]
- Setting up 256bit AES encryption between Linux OpenSwan and Cisco Pix 501 [read article]
Frank4DD, @2005-2007
Remote VPN Networking with the Cisco 831 Router
Introduced at the end of 2002, the Cisco 831 SOHO router is competing with the smaller, faster and easier configurable PIX 501 of Cisco's own making. Altough released one year after the PIX 501, with more then twice the physical size and housed in cheap plastic, are there any advantages? Well, if having a full-fledged Cisco IOS at your fingertips is one, than thats it. We will configure the 831 identical to the PIX site-to-site IPSEC VPN setup with NAT.
- Setting up a 3DES VPN between Linux FreeSwan and a Cisco 831 router together with source or destination network address translation [read article]
Frank4DD, @2005-2007
IP Subnetting Tables
These pages are quick reference sheets to identify network ranges for IPv4 subnetting. Manual calculation tends to be slow, and cumbersome.
- IPv4 Subnets in a table - The Class-'B' Subnet Cheat Sheet [show here]
- IPv4 Subnets in a table - The Class-'C' Subnet Cheat Sheet [show here]
Frank4DD, @2013-2014
First Hop Redundancy Protocols (FHRP)
This is a quick reference for First Hop Redundancy Protocols (FHRP), including HSRP, VRRP and GLBP.
- First Hop Redundancy Protocols (FHRP) - Overview (PDF) [see here]