“List vulnerable, high priority resources,” is a sensible step. In this day and age, the targets of distributed denial of service (DDoS) attacks are often key resources, such as servers hosting business critical applications and services, so you can pretty much count on those being negatively impacted during an attack. Creating backup copies of documents and lists of key personnel to contact in the event of an emergency is quite fundamental to any crisis management plan, but especially so when under a DDoS attack.
We’ve seen this with several recent attacks against financial institutions and others that used new malicious code to attack the DNS sub-system of the victim organizations. This type of attack brought the targets down in two ways; bandwidth exhaustion and by overwhelming processing capacity.
“Partner with an upstream provider,” includes a suggestion that Firewalls and Load Balancers can form part of your DDoS defenses but, in reality, that is not true. They may be able to protect themselves to a certain degree, from basic attacks, but any claimed DDoS defenses are likely to be basic, at best, and totally inadequate for ensuring business continuity. Modern firewalls are stateful, by design, making them unable to handle DDoS attacks, which are often created specifically to overwhelm that state tracking. Additionally, firewalls dictate which services may be used, but not how they are used. Attackers know this and often craft their attacks to specifically target those allowed services, or the servers which host them.
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