Let’s … DEFINE SIEM! But let’s define modern, today’s, circa 2017 SIEM since there is still confusion out there, it “siems”, especially in the area of “what is a SIEM”?” vs “what is a SIEM alternative?”
First, let’s start from our “official” definition – Gartner IT Glossary has this for SIEM: a “technology supports threat detection and security incident response through the real-time collection and historical analysis of security events from a wide variety of event and contextual data sources. It also supports compliance reporting and incident investigation through analysis of historical data from these sources” which makes sense, but still leaves some to imagination
In my head, I actually have a fairly clear definition of a SIEM. Unlike, say, security analytics, a modern SIEM can be defined fairly precisely. Let’s use our inputs/methods/use cases model that we invented for this paper.
The entry for SIEM will look like this:
|Inputs||Primarily event records / logs from many different sources, but also flows, a lot of context data, etc as context. Focus on: logs from many sources.|
|Methods||Primarily expert-written rules and static reports, but lately also other analytics (from stats to ML); methods run primarily in real-time and/or short time frame. Focus on: cross-device stateful correlation rules and reports.|
|Use cases||A very broad range of security use cases focused on threat detection, investigation and alert management, but also compliance reporting use cases. Focus on: no focus – whatever you make of it, broad scope but within security.|
So, this defines “SIEM DNA” as essentially…
- LOGS (from many sources, not merely one vendor) +
- CORRELATION / RULES in REAL-TIME | ACTIVITY REPORTS on stored data +
- BROAD SECURITY USE CASES =
The above I believe is what makes something a SIEM! Naturally, today’s best products analyze more than logs and use more than rules. In fact, in the past SIM was defined by reporting (compliance and security), while SEM was defined by real-time stateful correlation rules – this is the dark ages of 1997-2002. As a result, combined SIEM (since 2003) has been defined by both. Stateful rule-based correlation (and not simple matching alerts) and compliance reporting (and not just raw search) both require normalization, so it is implied in this definition. Today’s SIEM has grown to include other analytical methods (colliding with UEBA) and other sources of data (EDR-style agents, traffic and flows, etc).
Care to debate this one? I am aiming for simple/clear here, so it is entirely possible that I missed something.
So our Summer of SIEM continues…
Recent blog posts about SIEM:
- Is SIEM The Best Threat Detection Technology, Ever?
- SIEM or Log Management?
- Action Item: SaaS SIEM Users Sought!
- Flashback 2014: SIEM Deployment Blueprint Visual
- Summer of SIEM 2017 Coming…
- SIEM Future: A UEBA Path or An MDR Way?
Select popular blog posts about SIEM:
- Popular SIEM Starter Use Cases
- Detailed SIEM Use Case Example
- SIEM Use Cases – And Other Security Monitoring Use Cases Too!
- Our 2016 SIEM Papers Are Out!
Read Complimentary Relevant Research
How to Evaluate Cloud Service Provider Security
Security and risk management leaders continue to experience challenges to efficiently and reliably determine whether cloud service providers...
View Relevant Webinars
The Top 10 Basic Changes Needed for GDPR Compliance
The EU General Data Protection Regulation (GDPR) hovers over organizations like the sword of Damocles, with fines theoretically at an...
Comments or opinions expressed on this blog are those of the individual contributors only, and do not necessarily represent the views of Gartner, Inc. or its management. Readers may copy and redistribute blog postings on other blogs, or otherwise for private, non-commercial or journalistic purposes, with attribution to Gartner. This content may not be used for any other purposes in any other formats or media. The content on this blog is provided on an "as-is" basis. Gartner shall not be liable for any damages whatsoever arising out of the content or use of this blog.