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ICSL – Secure Communications
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ICSL COMSEC · Why ICSL?

Not every day is a sunny day.

Solutions that work · Even in real-world conditions

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Solutions that work

Security is only half the equation — it also has to work.

Silentel is secure and works in real-world conditions. In its own comparative tests (January–February 2025), ICSL tested several market-leading secure messengers. The result was clear.

Stable Voice Communications in Poor Network Conditions

Silentel remains stable and intelligible at up to ~50% packet loss — while most “secure” messengers fail at 20–30%. In ICSL tests, many promoted products proved to be fair-weather solutions only.

Call Behaviour Like a Normal Phone Call

Hold/resume, call switching, call waiting, robust signalling — even across mixed network scenarios. Many competitors lack these basic functions or implement them inconsistently.

No Data Traces on the Device — No Forensic Risk

Data remain encrypted on the server. Nothing remains on the device after logout — no local messages, no keys, no backups in iCloud or Google. Stolen device = no data loss.

Post-Quantum Cryptography — First NATO-Approved Product of Its Kind

In 2006, Silentel was the first NATO-approved software product for secure voice, video and data communications. The current version is NATO-approved with post-quantum cryptography — the first messenger product for government users with PQC implemented.

See how Silentel performs under load.

We will show you the comparative test results in a confidential briefing.