The incident response plan focuses on information security responses to incidents affecting systems and/or networks. It establishes procedures to address cyber attacks against an organization’s IT systems. These procedures are designed to enable security personnel to identify, mitigate, and recover from malicious computer incidents, such as unauthorized access to a system or data, denial of service, or unauthorized changes to system hardware or software. The continuity of support plan is the same as an IT contingency plan. It addresses IT system disruptions and establishes procedures for recovering a major application or general support system. It is not business process focused. The business continuity plan addresses business processes and provides procedures for sustaining essential business operations while recovering from a significant disruption. The continuity of operations plan addresses the subset of an organization’s missions that are deemed most critical and procedures to sustain these functions at an alternate site for up to 30 days.
Source: SWANSON, Marianne, & al., National Institute of Standards and Technology (NIST), NIST Special Publication 800-34, Contingency Planning Guide for Information Technology Systems, December 2001 (page 8).