IPSec deals with encrypting data over the network. What IPSec does is
protect data against those bad people with their protocol analysers.
Encryption prevents these network monitors capturing packets and reading
sensitive information inside. In my mind's eye, using IPSec is like putting
one of those clear cellophane envelopes in a sealed parcel.
Calculating IP Address ranges is a black art, which many network managers
solve by creating custom Excel spreadsheets. IPAT cracks this problem of
allocating IP addresses in networks in two ways:
For Mr Organized there is a nifty subnet calculator, you enter the network
address and the subnet mask, then IPAT works out the usable addresses and their
ranges. For Mr Lazy IPAT discovers and then displays the IP addresses of existing
computers.
Transport Mode is designed to ensure that traffic between two machines is
secure, for example the Financial Director and the CEO.
Tunnel Mode is to secure traffic between two networks and is particularly
useful for VPN traffic where you need encryption over the internet.
The diagram on the right gives a hint that there are a surprising number of
setting and properties for IPSec. In particular I recommend that you check
out the filtering tabs. (If necessary click and enlarge the thumb-nailed picture)
Guy Recommends: Orion's NPM - Network Performance Monitor
Orion's performance monitor is designed for detecting network outages. NPM makes it easy to see what's working, and what needs your attention.
This utility guides you through creating network maps. It also helps troubleshooting by indicating whether the root cause is faulty equipment, or resource overload.