Data aggregation: Log management aggregates data from many sources, including network, security, servers, databases, applications, providing the ability to consolidate monitored data to help avoid missing crucial events.
Correlation: looks for common attributes, and links events together into meaningful bundles. This technology provides the ability to perform a variety of correlation techniques to integrate different sources, in order to turn data into useful information. Correlation is typically a function of the Security Event Management portion of a full SIEM solution
Alerting: the automated analysis of correlated events and production of alerts, to notify recipients of immediate issues. Alerting can be to a dashboard, or sent via third party channels such as email.
Dashboards: Tools can take event data and turn it into informational charts to assist in seeing patterns, or identifying activity that is not forming a standard pattern.
Compliance: Applications can be employed to automate the gathering of compliance data, producing reports that adapt to existing security, governance and auditing processes.
Retention: employing long-term storage of historical data to facilitate correlation of data over time, and to provide the retention necessary for compliance requirements. Long term log data retention is critical in forensic investigations as it is unlikely that discovery of a network breach will be at the time of the breach occurring.
Forensic analysis: The ability to search across logs on different nodes and time periods based on specific criteria. This mitigates having to aggregate log information in your head or having to search through thousands and thousands of logs.
Security information and event management Wikipedia
In the field of computer security, security information and event management (SIEM) software products and services combine security information management (SIM) and security event management (SEM). They provide real-time analysis of security alerts generated by network hardware and applications.
Vendors sell SIEM as software, as appliances or as managed services; these products are also used to log security data and generate reports for compliance purposes.
The acronyms SEM, SIM and SIEM have been sometimes used interchangeably. The segment of security management that deals with real-time monitoring, correlation of events, notifications and console views is commonly known as security event management (SEM). The second area provides long-term storage as well as analysis and reporting of log data, and is known as security information management (SIM). As with many meanings and definitions of capabilities, evolving requirements continually shape derivatives of SIEM product-categories. Organizations are turning to big data platforms, such as Apache Hadoop, to complement SIEM capabilities by extending data storage capacity and analytic flexibility. The need for voice-centric visibility or vSIEM (voice security information and event management) provides a recent example of this evolution.
The term security information event management (SIEM), coined by Mark Nicolett and Amrit Williams of Gartner in 2005,the product capabilities of gathering, analyzing and presenting information from network and security devices
identity and access-management applications
vulnerability management and policy-compliance tools
operating-system, database and application logs
external threat data
A key focus is to monitor and help manage user and service privileges, directory services and other system-configuration changes; as well as providing log auditing and review and incident response.