Which protocol is known for providing a secure channel over an unsecured network?

The protocol known for providing a secure channel over an unsecured network is Secure Socket Layers (SSL). SSL is designed to provide encryption and secure data transmission between clients and servers, effectively protecting sensitive information such as personal details, payment information, and login credentials during their transfer over the internet.

SSL operates by establishing an encrypted connection between the client and server, ensuring that any data exchanged remains private and secure from potential eavesdropping or tampering by third parties. This is crucial for any online transactions or communications that require confidentiality and integrity.

Other options listed do not accurately refer to a widely recognized or established security protocol. For instance, "Standard Security Layer" and "Secure Signal Link" do not correspond to any well-known frameworks for secure communication. Similarly, "Simple Socket Layers" is not a valid term in the context of networking protocols and appears to be a misnomer related to SSL. Thus, SSL stands out as the correct and established protocol for securing communications across insecure networks.