1. It helps to limit the damage that can be done if one of your DMZ hosts is compromised. An external attacker only has access to equipment in the DMZ, rather than any other part of the network.
2. No, e-commerce uses internet for buying and selling products. Internet zone and private zone covers that.
3. Secure remote communications, VPN Firewall
4. No remote-access users are to have access to the internal network
5. DMZ zone must house production Internet services such as DNS, WWW server, Mail servers because these have to do with the internet and e-mails.
6. Internal network users are subject to an AUP restricting the use of their workstations and Internet connection for business purposes only because it only allows them certain functions that have to do with work only so they cannot spend time on goofing around during business hours.
7. It defines a system that is inspects network data flow, and when a security event occurs a team of analysts is there do their job. The main requirement for this type operation is a tuned IDS system to detect events that matter to the organization where something can be done in response to them.
8. Can be mitigated by performing content-aware, complete sessions are always being tracked for analysis, using both statistical and linguistic techniques for analysis, detecting, blocking and controlling the use of specific content based on rules and policies, monitoring network traffic, email traffic and multiple channels, blocking policy