If an organization wants to use a cloud service for BCDR, the location of the cloud hosting becomes a very important security consideration due to regulations and jurisdiction, which could be dramatically different from the organization's normal hosting locations. Availability is a hallmark of any cloud service provider, and likely will not be a prime consideration when an organization is considering using a cloud for BCDR; the same goes for self-service options. Resource pooling is common among all cloud systems and would not be a concern when an organization is dealing with the provisioning of resources during a disaster.

Explanation
Patents protect processes (as well as inventions, new plantlife, and decorative patterns). The other answers listed are answers to other questions.

An intrusion prevention system (IPS) can inspect traffic and detect any suspicious traffic based on a variety of factors, but it can also actively block such traffic. Although an IDS can detect the same types of suspicious traffic as an IPS, it is only design to alert, not to block. A firewall is only concerned with IP addresses, ports, and protocols; it cannot be used for the signature-based detection of traffic. A proxy can limit or direct traffic based on more extensive factors than a network firewall can, but it's not capable of using the same signature detection rules as an IPS.