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SSL/TLS Protocol Analyzer

Analyze SSL/TLS protocol configuration and supported protocols

About SSL/TLS Protocol Analyzer

Our free SSL/TLS Protocol Analyzer examines your server's protocol configuration, supported TLS versions, cipher suites, key exchange mechanisms, and authentication methods. Identifies outdated protocols and weak cipher configurations to help you maintain a strong security posture.

How to Use

  1. Enter the domain name of the server you want to analyze
  2. Click "Analyze" to perform a full protocol and cipher suite scan
  3. Review supported protocols, cipher components, and any vulnerabilities found

Use Cases

  • •Protocol compliance checking for regulatory requirements
  • •TLS version auditing to ensure only secure protocols are enabled
  • •Security posture assessment during penetration testing

Frequently Asked Questions

For maximum security, enable TLS 1.2 and TLS 1.3 only. TLS 1.0 and TLS 1.1 are deprecated and considered insecure. SSL 2.0 and SSL 3.0 should never be enabled under any circumstances.
A cipher suite is a combination of key exchange, authentication, encryption, and MAC algorithms used in TLS connections. Strong cipher suites use AEAD encryption like AES-GCM or ChaCha20-Poly1305 with ECDHE key exchange for forward secrecy.
Forward secrecy (using ECDHE key exchange) ensures that session encryption keys cannot be compromised even if the server's private key is later exposed. Each session uses unique ephemeral keys, so past communications remain secure even with key compromise.
An empty vulnerability list. That means the negotiated version is current, no component of the cipher is on the weak list — RC4, DES, 3DES, null, export and MD5 — and the key exchange provides forward secrecy. Each failing condition is listed by name, so a non-secure verdict always arrives with its reasons attached and the fix is implied by whichever line appears.
Because the configured cipher list and the accepted set are different claims. Offering one suite at a time asks the server a question it must answer honestly: can you complete a handshake restricted to exactly this? The ten-suite panel covers the modern mainstream plus the RSA fallbacks, and any fallback accepted alongside strong suites is the finding worth acting on.
That the suite negotiates keys with plain RSA, DH or ECDH rather than the ephemeral variants, so a future key compromise decrypts recorded traffic. The report flags suites whose names start with those prefixes without an ephemeral marker. Preferring ECDHE or DHE suites server-side resolves it while keeping compatibility with every modern client.
Scope. The downgrade page answers one question — which versions are accepted — with a risk grade. This report folds that per-version probing into a wider picture with cipher decomposition, vulnerability listing and suite acceptance. Use the downgrade page for a quick version verdict and this one when the answer needs the surrounding detail.
No — it opens on the order of twenty connections in sequence: the analysis handshake, six version probes and ten cipher probes, each with its own timeout. Slow or distant hosts stretch that further. A result that arrives after several seconds is normal; only a result that never arrives, ending in a connection error, indicates a problem with the target rather than the test.

What the Report Contains

This page builds a full protocol report from live connections: what this handshake negotiated, which versions the server accepts, and which of ten representative cipher suites it honors. Every section is measured at request time.

  1. 1Analyze the current handshake: protocol version, negotiated cipher broken into key exchange, authentication, encryption and MAC, plus a vulnerability pass flagging deprecated versions, weak components and static key exchange. A clean handshake reports secure with an empty list.
  2. 2Probe each protocol version from SSLv2 through TLS 1.3 with dedicated handshakes, listing exactly which ones the server completes. This is the same per-version technique as the downgrade page, folded into the wider report.
  3. 3Offer ten representative suites one at a time — ECDHE and DHE variants, GCM and ChaCha20-Poly1305, plus RSA-key-exchange fallbacks — and record which the server accepts. The accepted subset sketches the server's real cipher policy better than its configured list.

The report takes a few seconds because it opens many connections in sequence. A host that cannot be reached reports a connection error as its sole vulnerability rather than an empty report — the failure is data, and it is labeled as such.

Tips & Best Practices

  • •Use protocol analysis to understand TLS connection behavior
  • •Analyze protocol negotiation to diagnose compatibility issues
  • •Compare protocol analysis across different client configurations
  • •Document protocol analysis for security assessment evidence

Technical Details

Analysis: TLS protocol message flow and parameter analysis
Messages: Handshake, alert, application data, and change cipher spec
Debug: Protocol-level debugging and error identification
Output: Protocol analysis with message flow visualization

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