1. Scope and the five public tools
This statement applies to the free tools at www.paulioskos.com/tools/. No account or payment is required.
| Tool | Information processed | Where processing occurs |
|---|---|---|
| Backup Capacity Calculator | Protected-data size and unit, change rate, retention, backup frequency, reduction ratio, periodic-full interval, growth allowance, repository headroom, off-site copies and optional bandwidth. It calculates capacity, restore-point and transfer-time estimates. | Entirely in the visitor’s browser. |
| RPO/RTO & Downtime Cost Calculator | Recovery point and time objectives, value per hour, employee count and cost, additional hourly cost, changed data, expected outage and contingency. It calculates indicative exposure and a broad control pattern. | Entirely in the visitor’s browser. |
| SSL/TLS Certificate Checker | A public hostname. The server resolves it and reads the certificate and negotiated TLS details presented on TCP port 443. | The hostname is sent to the Paulioskos server; the server queries public DNS and the requested public TLS endpoint. |
| DNS Lookup | A public hostname and one selected record type: A, AAAA, CNAME, MX, NS, TXT, SOA, CAA or SRV. | The hostname and record type are sent to the Paulioskos server; the server queries its external DNS resolver and relevant authoritative DNS systems. |
| SPF Record Checker | A public domain and the published SPF TXT record, mechanisms, modifiers, includes and redirects reached within the safety budgets. | The domain is sent to the Paulioskos server; the server makes bounded public DNS queries. |
2. Browser and server processing
The two calculators use JavaScript in the browser. Their entered values and calculated results are not sent to the Paulioskos tool API, and the tool code does not place them in cookies, local storage or a Paulioskos database. They remain in the page until it is reset, replaced, closed or otherwise cleared by the browser. Loading the calculator page still creates an ordinary website request that may be handled by Cloudflare and the hosting path.
The three diagnostic tools submit a small JSON request over HTTPS to the Paulioskos server. Results are returned to the browser with Cache-Control: no-store, max-age=0, Pragma: no-cache and an expired Expires header. DNS and SPF result timestamps, and the TLS check time, are generated for the returned point-in-time result.
Public DNS records and public TLS certificates necessarily come from systems outside Paulioskos. DNS queries may pass through the server’s resolver to authoritative DNS infrastructure. The TLS checker connects to one already validated public address for the submitted hostname, while retaining the hostname for SNI and certificate matching.
3. Logging and retention
| Information | Current evidenced behaviour |
|---|---|
| Calculator inputs and results | Processed only in browser memory by the calculator code. They are not submitted to or retained by the Paulioskos application. |
| Diagnostic hostname or domain, DNS type and result | Processed in memory for the request and returned to the browser. The tool route contains no database insert, file write or successful-request logging, so the application does not deliberately retain these values or results. |
| Result timestamps | Generated in memory and included in the response. They are not deliberately retained by the tool application. |
| Visitor IP address | Express derives the source IP using the configured single trusted-proxy hop. The per-IP limiter holds the IP-derived key and request count in process memory for the active 15-minute rate-limit window. This store is not persistent and is also lost if the process restarts. The tool handler does not copy the IP into a database, file or application log. |
| User agent | The tool route does not read or store the user-agent header. Cloudflare or other infrastructure in the request path may process it as ordinary traffic or security metadata. |
| Application container logs | Express has no HTTP access-logging middleware and ordinary successful tool requests are not written to stdout or stderr. Service lifecycle, database, mail, administration and unexpected operational errors can be logged. Under the supplied Docker Compose configuration, each container uses the Docker json-file driver with three compressed files of at most 10 MB each. Rotation is size-based, not a fixed number of days. |
| Cloudflare edge traffic and security metadata | Cloudflare provides DNS, TLS edge, reverse proxy and security filtering and may create records including IP address, timestamp, requested path, user agent, response or security-event information. The repository does not define or evidence Cloudflare’s active plan-level log-retention period; it is controlled by the deployed Cloudflare configuration and provider terms. Paulioskos therefore does not claim that edge metadata is never logged or promise an unsupported exact period. The general Website Privacy Notice states the organisation’s normal 90-day position for routine security and access logs, subject to provider controls and longer preservation where an incident, complaint, legal hold or continuing threat requires it. |
Tool inputs and results are not used for advertising, behavioural profiling or marketing. The public tools contain no marketing opt-in, analytics, advertising pixel or remarketing integration evidenced by the current repository.
4. Security and abuse-prevention controls
- Diagnostic requests must be strict JSON bodies no larger than 2 KB and may contain only the expected fields.
- Hostnames are normalised and validated; URLs, ports, paths, literal IP addresses, single-label names and local or internal suffixes are rejected.
- Default limits are 30 diagnostic requests per source IP and 300 globally in each 15-minute window.
- Bounded concurrency permits at most 12 DNS/SPF operations and six TLS operations at once by default; excess work is rejected rather than queued without limit.
- DNS answers, record lengths and certificate fields are capped. DNS operations normally time out after five seconds.
- SPF analysis has a maximum nesting depth of six, a 20-query DNS budget and bounded include/redirect traversal. It reports when the result is incomplete.
- The TLS checker first resolves every returned address and rejects the request if any address is private, local, reserved, documentation, multicast or otherwise non-public. It connects directly to a validated address to reduce DNS-rebinding and server-side request forgery risk.
- TLS connections are restricted to fixed TCP port 443, normally time out after six seconds, use the submitted hostname for SNI and certificate identity checking, and do not accept a visitor-supplied resolver or port.
- Diagnostic responses are marked no-store and unexpected server errors are sanitised before return.
These controls reduce risk; they do not make any Internet-facing service immune from misuse, outage or security defects.
5. Acceptable use
The tools are intended for proportionate manual planning and legitimate checks of public information. You must not:
- run automated bulk, high-frequency or distributed querying;
- attempt to evade, reset, bypass or interfere with rate, concurrency, query or validation limits;
- carry out denial-of-service activity, deliberate resource exhaustion or testing likely to degrade the service;
- use the tools for unlawful testing, unauthorised access, harassment, surveillance or interference with a third party’s systems;
- submit deceptive or manipulated inputs intended to exploit the application, resolver, network or a third-party service; or
- misrepresent a result as authorisation, certification, assurance or proof of security.
Public availability is not permission to test Paulioskos or any third party beyond the ordinary function of the tool. Suspected vulnerabilities must be handled under the existing Responsible Vulnerability Disclosure Policy; this statement does not replace or expand that policy.
Paulioskos may throttle, challenge, temporarily block or permanently restrict access that appears abusive, unsafe, unlawful or likely to affect service availability or third-party systems. Where appropriate, relevant evidence may be preserved and activity may be reported to a provider or competent authority.
6. Results and limitations
Calculator outputs are planning estimates based only on the assumptions entered. Diagnostic outputs are point-in-time observations of public DNS or TLS information available to the server at the time of the request. DNS caching, network paths, resolver behaviour, certificate deployment and third-party configuration can change the result.
No output is a guarantee, certification, audit opinion, legal or regulatory conclusion, professional engineering design or substitute for business impact analysis, dependency mapping, security review, architecture, tested recovery procedures or qualified advice. Validate important decisions and production changes independently.
7. Privacy and security contacts
| Purpose | Route |
|---|---|
| Privacy questions and rights | [email protected] and the Website Privacy Notice |
| Security vulnerability reports | [email protected] and the Responsible Vulnerability Disclosure Policy |
| General document questions | [email protected] |