Administrators should investigate complaints about attacks that allegedly emanate from their networks. Many ISPs simply do not do so, though businesses are in a better position to respond because they have far fewer dial-up users to track. The truth is, there is very little that e-commerce sites can do to avoid being the target of a distributed denial of service attack,' says security consultant Rik Farrow. Instead, Farrow agrees with SANS that network administrators should concentrate on securing their networks against being used as a platform from which to mount attacks. The options depend on the topography of the site.
Smaller companies tend to have their sites hosted by third parties.
If that is the case, it is worth installing a firewall on the line and learning how to configure its rule-set to filter everything except the type of traffic that is expected to flow between the host's Web server and the organisation's database. If a firm has the resources to host its own Web server, it may have separated the Web server from the application server and will have certainly separated the Web server from the database server. A firewall can be set to drop unwanted traffic between the two sub-networks. The same approach is effective for protecting all internal machines from becoming the unintended hosts for Trojans. A properly configured NAT router can be used to permanently forward particular types of traffic to specific machines within a network, enabling the IP address to be hidden from all but the most sophisticated cracker.