Network Security

Posix has various ways of securing networks. The most common way of securing a network, is by setting up a NAT (Network Address Translation) service on a Linux box (or Cisco router), and have the inside network on non-routable (RFC1918) IP addresses. This ensures that the outside world cannot route DIRECTLY into the LAN, and would have to go through the NAT . The inside network has no way of connecting to the Internet without first being translated from a non-routable address, to an accepted Internet address.


Another way, is to set up a Linux server to run 'ip-chains ' which is a firewall that is currently largely used by companies who do not want to spend over R 80 000.00 for a firewall that does EXACTLY the same! The Linux firewall comes standard with the distribution kit, and has no extra cost implications.


Depending on the model of the Cisco, and the available RAM i nside, the router itself can be transformed into a Firewall. This allows the client the safety in knowing that non-wanted packets cannot even enter the LAN segment of the network, and stops attacks on the furthest point away from the client information. Two levels of security can be used, one on either side of the dedicated link.


As Posix is a proud member of the Linux Professionals Association, we do Linux support in all the above-mentioned scenarios.

Posix also boasts the CCIE qualifications from Cisco, which allows the client Peace of Mind and assurance, that we can set up and configure Cisco routers for anything from Internet peering to BGP to Firewalls.