Secure Real-Time Transport Protocol (SRTP) is a security protocol used to encrypt and authenticate the streaming of audio and video over IP networks. It ensures that the video streams from the IP cameras are both encrypted to prevent unauthorized access and authenticated to verify the integrity of the stream, making it the ideal choice for securing video surveillance.

Serverless architecture allows companies to deploy code without managing the underlying infrastructure. This approach significantly reduces the time and expense involved in code deployment because developers can focus solely on writing code, while the cloud provider manages the servers, scaling, and maintenance.
Serverless computing also enables automatic scaling and pay-per-execution billing, which further optimizes costs.
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CompTIA Security+ SY0-701 Course Content: The course covers cloud technologies, including serverless architectures, which are highlighted as a method to streamline and reduce costs associated with code deployment.

Code signing is a technique that uses cryptography to verify the authenticity and integrity of the code created by the company. Code signing involves applying a digital signature to the code using a private key that only the company possesses. The digital signature can be verified by anyone who has the corresponding public key, which can be distributed through a trusted certificate authority. Code signing can prevent unauthorized modifications, tampering, or malware injection into the code, and it can also assure the users that the code is from a legitimate source. References = CompTIA Security+ Study Guide with over 500 Practice Test Questions: Exam SY0-701, 9th Edition, Chapter 2, page 74. CompTIA Security+ (SY0-701) Certification Exam Objectives, Domain 3.2, page 11. Application Security - SY0-601 CompTIA Security+ : 3.2

Cryptojacking is the likely cause in this scenario. It involves malware that hijacks the resources of infected computers to mine cryptocurrency, usually without the user's knowledge. This type of attack doesn't typically degrade performance significantly or result in obvious system failures, which matches the situation described, where the machines showed no signs of degraded performance or excessive failed logins.
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* CompTIA Security+ SY0-701 Course Content: Cryptojacking is covered under types of malware attacks, highlighting its stealthy nature and impact on infected systems.

Within an organization's Software Development Life Cycle (SDLC), an Information Security Policy is a vital component. It outlines the rules and procedures for ensuring that the organization's IT assets and data are protected throughout the development process. Ensuring secure coding practices, access controls, and regular security testing is fundamental in preventing vulnerabilities in applications.
Other options like service-level agreements and branch protection requirements are less likely to be integral to SDLC processes. Penetration testing methodology, while useful, is generally considered outside the scope of the SDLC.