What does Mean Time to Detect (MTTD) mean?

The "Mean Time to Detect" is a metric from the IT sector, more precisely from Incident Response Management. It provides information about how quickly a devops security team is able to detect problems. These can be software or hardware errors, for example. Although this value appears to offer little added value at first glance, it is critical to success. After all, system downtime costs large and small midsize businesses (SMBs) significant amounts of money year after year.

Explanation and definition: Mean Time to Detect (MTTD)

The abbreviation "MTTD" stands for Mean Time to Detect. Another common term is "Mean Time to Discover". Both terms originate from the field of incident management. MTTD provides information about the time required to detect a security problem.
For security incident response, a short Mean Time to Detect is critical. After all, it is better to detect incidents early and resolve them as quickly as possible. This often allows problems to be resolved before they can cause widespread damage to the system. A classic example of this is malware that enters the corporate network. Over time, it can cause immense problems. If this malware can be detected quickly enough, the damage is usually limited. This makes the Mean Time to Detect an important key figure in the company.
At the same time, mean time to detect is a barometer for assessing the incident management capabilities of teams. Thus, based on the analysis results, previous strategies can be rethought and redefined. This ultimately enables a better response to failures and system problems. On the other hand, if the value is satisfactory or exceeds expectations, it indicates the right course of action.

Calculating MTTD in IT practice

The formula for Mean Time to Detect is basically very simple. It is the sum of all the times it takes to identify incidents. Then the total time is divided by the number of all incidents.

• First, the company defines a time period that should be decisive for the Mean Time to Detect. Here, those responsible often opt for a monthly calculation. It is a good indication of how good the security measures are. At the same time, monthly calculations make it possible to adjust procedures more quickly. A prior vulnerability scan helps identify pre-existing problems.
• The next step is to determine which techniques and tools should be used in determining MTTD. These may include intrusion detection systems, automated security scans, penetration tests or user help desk tickets.
• With the help of the logs, helpdesk tickets and the intrusion detection system, the responsible employees keep track of all incidents.
• The tools used help define and record the start and detection times for incidents. This ensures that all incidents are included in the metrics.
• To determine Mean Time to Detect, divide the total time by the number of incidents. This results in a factor that further defines the performance in this area. The higher it is, the longer the team's response time. If the MTTD is too high, it is advisable to adjust the existing processes and mechanisms. In this way, response times can be shortened in the future.

A trend can be seen by comparing this value with the MTTD from previous months. Good software also helps to keep track of this crucial key figure.
Important: Similar to so-called pentests, a categorization or gradation of individual incidents makes sense. After all, not all problems weigh the same. It is therefore better to prioritize serious incidents. Since this approach can have an impact on the Mean Time to Detect, many organizations take a different approach: They classify incidents into different categories and determine a separate MTTD for each. In this way, several values are obtained that can provide a higher level of significance than the general factor.

Importance of Mean Time to Detect (MTTD) for Troubleshooting

Modern security platforms and new security strategies contribute significantly to higher security in companies. Nevertheless, errors or vulnerabilities cannot be completely avoided. The Mean Time to Detect should help to get an overview of the current situation. After all, the sooner an organization identifies problems, the sooner it can rectify these incidents. On the one hand, this approach helps to avoid major damage, and on the other hand, it is easier and cheaper to take action at an early stage.
At the same time, MTTD is a valuable metric for organizations introducing DevOps to the enterprise. Finally, Mean Time to Detect provides insight into where there is potential for improvement in the process. Among other things, it can help determine how good log management and monitoring strategies really are. The lower the mean time to detect, the healthier the incident management. If, on the other hand, the factor is too high, new approaches might be a good idea.

Other metrics and KPIs: Failure metrics in IT

In addition to MTTD, there are other indicators that are relevant when troubleshooting IT problems. Some are directly related to Mean Time to Detect, while others are complementary.

Mean Time to Restore

Mean Time to Restore is based on Mean Time to Detect. This metric describes how long it takes overall for a problem to be fixed. Together, the MTTR and MTTD provide information about the general ability of a team to fix errors.

Mean Time between Failures

The "Mean Time between Failures" describes the period of time between two incidents. Thus, the focus of MTBF is on IT provisioning without performance failures or performance degradation.

Initial resolution rate

This value shows the company how efficient the team is at resolving problems.

Downtime

This percentage indicates the amount of time the system is running reliably. In most cases, downtime refers to a fiscal year, but it can also focus on other time periods.

Conclusion

In the modern business world, IT incidents represent a serious risk. They impair the company's ability to respond and, in the worst case, lead to financial losses. Mean Time to Detect is an important metric in this area. It helps to understand how quickly the company or its IT department can respond to incidents. At the same time, it shows where there is room for improvement to ensure consistent availability of systems. This makes Mean Time to Detect important for any company that needs to respond independently to IT incidents.