Security Information & Event Management - A complete Guide

On November 4, 2022

What is SIEM?

Security Information and event management (SIEM) is a part of the cyber security field which constitutes security information management (SIM) and security event management (SEM).

SIEM generates real-time security alerts, logs security data, and reports for the purpose of compliance. The SIEM tools are used by Security Operations Center (SOC) analysts to detect and manage security incidents, and report potential threats.

SIEM helps in collection and storage of data, it investigates and mitigates threats, and helps in data reporting.

Why is SIEM important?

SIEM helps in real-time monitoring of events and a total analysis and tracking of them. It further logs security data for compliance and auditing purposes.

How does SIEM work?

The main function of SIEM is to collect and aggregate data and consolidate into a single platform for easy identification of threats. Some other functions include:

  • Log management -

It is significantly easier to manage data that is all under a single roof. SIEM does exactly that by collecting a wide range of data from across all cloud environments, networks, users, applications, assets etc. It enables the security team to manage the network’s log and data much more effectively from a single centralized location. Some SIEM solutions are further designed to integrate third-party intelligence inputs received and correlate them with previously recognized threat signatures and profiles. Thus, new types of attack signatures are effectively recognized and deterred from attacking the network.

  • Event correlation and analytics -

Manual detection and correlation of data for an in-depth analysis takes a lot of time. In order to overcome this disadvantage, SIEM solution uses advanced analytics to study and understand the data pattern, correlate events, and provide insight into identifying and locating the potential threats. It significantly improves mean time to detect (MTTD) and mean time to respond (MTTR).

  • Incident monitoring and security alerts -

Due to centralized management of data, both on-premise and in cloud environments, SIEM is able to identify all entities of the IT environment. All users, devices, applications, and networks, are monitored effectively for security incidents such as abnormal behavior, behavior anomalies and classifying them accordingly.

A predetermined set of correlation rules enable the administrators to take appropriate and timely action to deter the attacks and prevent a malfunction before it accelerates into a major security incident.

  • Compliance management and reporting -

SIEM plays an important role in helping organizations adhere to compliance standards. Due to its significant role in data collection and analysis, SIEM helps in verifying compliance data across the entire network and infrastructure. It generates real time compliance reports for HIPPA, SOX, PCI-DSS, GDPR and various other compliance standards.

This further eases the burden on security management and detects potential violations early on for generating remediation solutions. SIEM solutions also generate automatic reports that meet the compliance requirements.

Benefits of SIEM

Irrespective of the size of the organization, it is imperative to take proactive steps in mitigating threats and preventing their occurrence to the extent possible. Some of the benefits of SIEM include:


  • Improved interdepartmental efficiency- SIEM provides wide visibility of IT environments, which in turn helps in improving efficiency between various departments. This helps the teams to collaborate and handle threats much more proactively and efficiently.

  • Increased automation capabilities- SIEM integrates seamlessly with SOAR Security Orchestration Automation and Response) capabilities to manage businesses saving both time and resources. Using artificial intelligence and machine learning, complex threats are identified and responded to, in significantly less time as compared to physical teams.

  • Detects unknown threats in advance- Given the fact the security landscape alters ever so frequently, it is ideal security behavior to be able to detect and respond to both known and unknown threats. Threats such as insider threats, phishing attacks, SQL injections, DDoS attacks, data exfiltration are modern-day security breaches that affect organizations on a regular basis.

  • Aids in compliance and regulatory auditing- Compliance auditing and reporting happens across a centralized server due to SIEM solutions which makes it easy to collect and analyze system logs. This results in decreased use of internal resources while meeting all the required compliance reporting standards.

  • Recognizing real-time threats- SIEM solutions help strengthen security posture due to active monitoring solutions across the entire infrastructure. The time required to identify and respond to potential threats is considerably reduced.

  • Aids in forensic investigations- Digital forensic investigations are easy to conduct with the help of SIEM solutions. Since all the system logs and events are placed in a single location, it is easy to collect and analyze. Past incidents can then be recreated and new events can be checked for any suspicious activity and accordingly security measures can be implemented.

  • Manages reports necessary for compliance- Organizations need to adhere to strict compliance and regulatory bodies which can be a challenging task considering the mammoth amount of data involved.

Real-time audits and on-demand reporting of regulatory compliance are provided by SIEM solutions which hugely benefit the organizations by reducing their resource expenditure.

  • Monitors users and applications- With significant rise in remote working and consequently the use of SaaS applications and BYOD (bring your own device) policies, organizations look to greater visibility to mitigate risks from outside sources apart from the network perimeter.

Transparency is considerably increased across all users, applications, and devices by SIEM solutions thereby enabling threat detection regardless of from where and how digital assets are accessed.

Tools and features involved in a SIEM solution

  • Network visibility Visibility into network flows is attained by inspecting packet captures that give insights into the IP addresses and protocols that may reveal malicious files detected across the network.

  • Threat intelligence SIEM solutions must include open-source intelligence to counter attack modern day vulnerabilities.

  • Log data management SIEM solutions play a major role in gathering data and placing them in a centralized server for ease of use. This helps in analysis, increases productivity, and efficiency.

  • Real-time alerting SIEM solutions can be customized according to the needs of the organization in generating alerts based on levels, sending notifications etc.

  • Analytics SIEM, with the help of artificial intelligence and machine learning, can help thwart more advanced and sophisticated threats.

  • IT compliance Organizations have to adhere to strict compliance standards which can vary depending on coverage and priorities. SIEM solutions allow for full compliance coverage and auditing requirements and even on-demand reporting if opted.

  • Dashboards and reporting With a large amount of data involved in organizations which can report thousands of events per day, SIEM works towards understanding and reporting incidents with no time lag.

  • Security and IT integrations Seamless integration of existing security investments along with SIEM solutions generates visibility across the network infrastructure.

SIEM implementation best practices

  1. Understand the scope of implementation of the SIEM solution installed and how best your organization will benefit from its setup.

  1. Integrate any preexisting security solutions with SIEM and apply your preexisting data correlation rules across all systems including cloud environments.

  1. Know your compliance requirements and ensure that SIEM solutions provide all the necessary audit reporting in real time.

  1. In order to collect log data, detect threats and access abuses, and monitor network activity, classify all your digital assets across the network and infrastructure.

  1. Taking into account the increase in use of remote devices, generate BYOD (bring your own devices) policies, IT configurations and restrictions while integrating with SIEM.

  1. Regularly update and tune your SIEM solutions in order to reduce the number of false positives that may be generated.

  1. Ensure that all departments work together while documenting and practicing the incident response plans in order to respond effectively.

  1. Use other tools to integrate with SIEM by incorporating artificial intelligence and machine learning and SOAR (security orchestration automation and response) capabilities.

  1. Consider outsourcing to a third-party vendor who will be a MSSP (managed security service provider) who can manage your SIEM deployments and other complexities to improve functionality while you focus on accelerating your business.

SIEM use cases

SIEM has demonstrated a number of useful ways in which it helps in cyber security. Some of the use cases are:

  1. Data aggregation SIEM helps in collecting data not only from servers and network device logs but also from endpoint security, authentication and authorization systems, cloud services, applications, network security devices, online databases, etc. SIEM also helps businesses as they scale and ensures visibility across applications, users, devices, third-party vendors, databases etc.

  1. Compliance User monitoring is mandated across all compliance and regulatory bodies. SIEM tools are used to monitor all user activity and report any suspicious behavior or alerts or if any violation of policy is noted.

  1. Threat Prevention At the time of monitoring, all suspicious behavior or system anomalies are noted which are then used for real-time notification, trend analysis and for further forensic investigations.

  1. Data Storage Storage of data helps in correlation over long periods of time and also assists in compliance. It further helps security analysts to do a forensic investigation in case of a data breach.

Frequently asked questions

1. How does SIEM work?

SIEM aims to make data easily accessible from a single platform. It aggregates the data collected from endpoint devices, security applications, security devices, and network infrastructure.

It then goes on categorizing them into actionable items and is thus able to isolate any deviations. The security incident response team is then able to easily investigate these alerts.

Moreover, SIEM solutions are compatible to work in any environment be it on-premises, hybrid, or cloud-based. In fact, SIEM solutions work faster and are simpler to deploy in cloud-based environments.

It is also easier to scale the solutions according to the requirements in case of an increase in data.

2. What are the capabilities of SIEM?

The main function of SIEM is to aggregate and consolidate data into a single system for easy search and report purposes.

Some of the key SIEM capabilities are:

  • Search, monitor, alert, and investigate data
  • Check behavior across organization
  • Check system for anomalies and unusual activity
  • Consolidate all incidents related to security once they are generated
  • Predicting threats in advance and adding context to the security events
  • Analyze the breaches and provide valid inputs by searching and reporting the data collected
  • Investigate all attacks and analyze the incidents and breaches
  • Provide valuable intel for compliance purposes

3. What are the limitations of SIEM?

SIEM, although a very useful tool, comes with its share of disadvantages. For one, it is very expensive and is resource intensive. Although useful in data analytics, it generates gaps while identifying anomalies. In such cases, user and entity behavior analysis (UEBA) is used.

Moreover, it lacks effective incident response mechanisms. Thus, a careful vetting process of cyber security vendors must be carried out by organizations based on their needs and requirements in order to avoid being overwhelmed by too many alerts, false positives, and other anomalies.

4. What is the need for a SIEM?

Depending on an organization’s functionality it should determine whether it actually requires a SIEM solution else it will only be wasting money and resources unnecessarily. Meanwhile there are many other solutions that are worth exploring such as managed security services, managed detection and response services.

Central log management is another solution towards SIEM that helps view the log data and help in troubleshooting issues and supporting other business needs. Although SIEM provides much more capable solutions.

Conclusion - The future of SIEM

Due to the high level of sophisticated threats that are emerging, it has become crucial to come up with solutions that are equally capable of thwarting the attacks effectively.

One such solution is the XSIAM i.e., the extended security intelligence and automation management. It uses artificial intelligence (AI) to reimagine how threats are remediated using automation. This leads to better security with almost real-time detection and response.

It further overrides the need to manually manage information and events.

Moreover, with the increase in use of endpoints, AI plays a pivotal role in improving the cognitive capabilities of the system to make appropriate decisions. While SIEM adapts to accommodate growing endpoints, AI provides solutions to the complex and evolving threat landscape.

It is imperative to invest in a SIEM solution from a provider that you can trust who understands the need for a strong security posture.