handshakelevel

Handshakelevel is a conceptual and sometimes programmatic indicator used to describe the progress and security parameter negotiation during a cryptographic handshake between two networked endpoints. It captures the current stage of the handshake, from initiation to the establishment of a secure channel.

In many protocol implementations, handshake level is represented as an enumerated value or numeric counter. Common stages include initial contact, negotiation of capabilities or parameters, peer authentication, key exchange, and completion of the handshake. The precise stages and their ordering vary by protocol, so the term is not standardized across technologies.

Purpose and usage: Handshakelevel is often exposed by libraries or logs to aid debugging, diagnostics, and policy enforcement. It allows software to decide when to retry, drop a connection, or apply security checks based on what has been negotiated so far. It can also be used to measure handshake latency by stage.

Examples and scope: In Transport Layer Security (TLS), the conceptual stages include ClientHello, ServerHello, certificate exchange, and key exchange, culminating in the Finished messages; in SSH, negotiation of algorithms and host authentication represent levels. Other protocols, such as WebRTC or VPN tunnels, implement analogous progress indicators.

Security considerations: Since handshakelevel reflects progress rather than final security guarantees, systems should not assume security until the maximum level is reached and post-handshake validation succeeds. Clear definitions and consistent mappings are important for interoperability.