Summarizing precision and recall Sometimes, you might want to use a metric that summarizes precision and recall, instead of prioritizing one over the other. Two very popular metrics can be used to summarize precision and recall: F1 score and Area Under Curve (AUC). The F1 score, also known as the F-measure, computes the harmonic mean […]

Note If you were trying to do this for a large number of instances in an automated fashion, then the best course of action would be to label those instances to get the CloudWatch agent with a particular tag and value – for example, CloudWatchAgent as the tag and the date as the value. This way, you […]

GENEVE The GENEVE protocol was covered in Chapter 4, “Load Balancing,” as part of the gateway load balancer. In this section, we will do a brief refresher of this standardized encapsulation protocol. The GENEVE protocol preserves the original packet by providing an encapsulation protocol that supports transparent routing. To make sure that the original packet […]

VPC Connectivity This section covers the following objective of Domain 5 (Networking and Content Delivery) from the official AWS Certified SysOps Administrator – Associate (SOA-C02) exam guide: 5.1 Implement networking features and connectivity CramSaver If you can correctly answer these questions before going through this section, save time by skimming the Exam Alerts in this […]

IPSec IPSec provides encapsulation of packets that are encrypted in transit between endpoint devices. IPSec is actually a family of protocols that work together for end-to-end encryption of data flows. IPSec will encrypt the packets and can authenticate the source of where the packets came from. It is the most common method used on networks […]

for Loop: The for loop is used to iterate over a range of values for a specified number of times. It is a procedural loop used to execute a block of code repeatedly for a predetermined number of iterations. for (Integer i = 0; i < 10; i++) { System.debug(‘The value of i is: ‘ […]

Elastic Network Interfaces An Elastic Network Interface (ENI) is a virtual network interface in a VPC. When EC2 instances are created in a VPC, they automatically get a default network interface (eth0). This interface cannot be detached from this instance. You can choose to have a public IP address automatically assigned to this interface. However, […]

VxLan Virtual Extensible LAN (VxLAN) is a standardized encapsulation protocol that stretches layer 2 connections over a layer 3 routed network, and it is primarily used in larger enterprises, service providers, and cloud data centers. VxLAN is an overlay encapsulation protocol that scales up to 16 million logical networks by adding a 24-bit ID to […]

Writing a main() Method A Java program begins execution with its main() method. In this section, you learn how to create one, pass a parameter, and run a program. The main() method is often called an entry point into the program, because it is the starting point that the JVM looks for when it begins […]

Extracting metrics from a confusion matrix The simplest metric that can be extracted from a confusion matrix is known as accuracy. Accuracy is given by the following equation, as shown in Figure 7.2: Figure 7.2 – Formula for accuracy For the sake of demonstration, Figure 7.3 shows a confusion matrix with data. Figure 7.3 – […]