Monday, July 31, 2023

Ruminating on Differential Privacy

Differential privacy (DP) is a mathematical paradigm for protecting individuals' privacy in datasets. By allowing data to be analysed without disclosing sensitive information about any individual in the dataset, it can protects the privacy of individuals. Thus, it is a method of protecting the privacy of people in a dataset while maintaining the dataset's overall usefulness.

To protect privacy, the most easy option is anonymization, which removes identifying information. A person's name, for example, may be erased from a medical record. Unfortunately, anonymization is rarely enough to provide privacy because the remaining information might be uniquely identifiable. For example, given a person's gender, postal code, age, ethnicity, and height, it may be able to identify them uniquely even in a massive database.

The concept behind differential privacy is to introduce noise into the data in such a manner that it is hard to verify whether any specific individual's data was included in the dataset. This is accomplished by assigning a random value to each data point, which is chosen in such a manner that it has no effect on the overall statistics of the dataset but makes identifying individual data points more difficult.

The following paper by Apple gives a very good overview of how Apple uses Differential Privacy to gain insight into what many Apple users are doing, while helping to preserve the privacy of individual users -

Epsilon (ε) is a parameter in differential privacy that affects the amount of noise introduced to the data. A greater epsilon number adds more noise, which gives more privacy but affects the accuracy of the findings.

Here are some examples of epsilon values that might be used in different applications:

  • Healthcare: Epsilon might be set to a small value, such as 0.01, to ensure that the privacy of patients is protected.
  • Marketing: Epsilon might be set to a larger value, such as 1.0, to allow for more accurate results.
  • Government: Epsilon might be set to a very large value, such as 100.0, to allow for the analysis of large datasets without compromising the privacy of individuals.
Thus, the epsilon value chosen represents a trade-off between privacy and accuracy. The lower the epsilon number, the more private the data will be, but the findings will be less accurate. The greater the epsilon number, the more accurate the findings will be, but the data will be less private.
A deep dive into these techniques is illustrated in this paper -

Thursday, July 20, 2023

Ruminating on and Let's Encrypt is a free, open-source service that allows you to use wildcard DNS for any IP address. This implies you may build a hostname that resolves to any IP address, no matter where it is. This may be beneficial for a number of things, including:

  • Testing local machine applications. When constructing a local application, you may utilise to provide it a hostname that can be accessed from anywhere. This makes it simpler to test and distribute the application with others. This service has been made free by a company called as Powerdns. Examples: 
    • maps to
    • maps to
    • maps to  (hexadecimal format)
  • Many online services expect a hostname and do not accept an IP address. In such cases, you can simple append * at the end of the public IP address and get a OOTB domain name :)
  • Creae a SSL certificate using letsencrypt:  If you use the "dash" and "hexadecimal" notation of, then you can easily create a public SSL certificate using "Let's Encrypt" that would be honoured by all browsers. No need of struggling with self-signed certificates. 
ngrok is another great tool that should be in the arsenal of every developer. 

Monday, July 03, 2023

Ruminating on Observability

It is more critical than ever in today's complex and dispersed IT settings to have a complete grasp of how your systems are performing. This is where the concept of observability comes into play. The capacity to comprehend the condition of a system by gathering and analysing data from various sources is referred to as observability.

Observabilty has three critical pillars: 

  • Distributed Logging (using ELK, Splunk)
  • Metrics (performance instrumentation in code)
  • Tracing (E2E visibility across the tech stack)

Distributed Logging: Logs keep track of events that happen in a system. They may be used to discover problems, performance bottlenecks, and the flow of traffic through a system. In a modern scalable distributed architecture, we need logging frameworks that support collection and ingestion of logs across the complete tech stack. Platforms such as Splunk and ELK (Elastic, Logstash, Kibana) support this and are popular frameworks for distributed logging. 

Metrics (performance instrumentation in code): Metrics are numerical measures of a system's status. They may be used to monitor CPU use, memory consumption, and request latency, among other things. Some of the most popular frameworks for metrics are Micrometer , Prometheus and DropWizard Metrics

Tracing (E2E visibility across the tech stack): Traces are a record of a request's route through a system. They may be utilised to determine the core cause of performance issues and to comprehend how various system components interact with one another. A unique Trace-ID is used to corelate the request across all the components of the tech stack. 

Platforms such as Dynatrace, AppDynamics and DataDog provide comprehensive features to implement all aspects of Observability. 

The three observability pillars operate together to offer a complete picture of a system's behaviour. By collecting and analysing data from all three sources, you can acquire a thorough picture of how your systems operate and discover possible issues before they affect your consumers.

There are a number of benefits to implementing the three pillars of observability. These benefits include:

  • The ability to identify and troubleshoot problems faster
  • The ability to improve performance and reliability
  • The ability to make better decisions about system design and architecture

If you want to increase the observability of your systems, I recommend that you study more about the three pillars of observability and the many techniques to apply them. You can take your IT operations to the next level if you have a thorough grasp of observability.