What is AES-256-GCM?
TL;DR:
AES-256 (Advanced Encryption Standard with a 256-bit key) is the most secure symmetric encryption algorithm currently known to man. It is the same standard used by the NSA, banks, and governments to protect Top Secret information. TaskNote adds GCM (Galois/Counter Mode) to make it faster and to prevent anyone from tampering with your data.
🏛️ The "Gold Standard" Analogy
If your Encryption Key is the physical key, then AES-256 is the design of the safe itself.
- AES: Imagine a safe made of a material that cannot be drilled, melted, or blown up.
- 256-bit: This refers to the thickness of the safe walls. 256 is the maximum thickness available.
- GCM: Imagine this safe has a built-in alarm system. If someone tries to scratch the paint or modify the safe while it's locked, the alarm triggers instantly (this is called "Integrity Check").
🧮 How Secure is "256-bit"?
It is hard for the human brain to comprehend how strong AES-256 is.
To crack a single AES-256 key using a "Brute Force" attack (trying every possible combination), you would need a supercomputer that consumes the energy of a star.
- Combinations: 2256 possibilities.
- Time to crack: Even if you used all the computers on Earth, it would take longer than the age of the Universe to find the key.
This is why, when we say your data is secure, we aren't relying on hope. We are relying on physics.
⚡ Why We Use GCM Mode (Speed + Integrity)
Not all AES encryption is the same. Many older apps use AES-CBC (Cipher Block Chaining), which can be slow and vulnerable to "Padding Oracle" attacks.
TaskNote uses AES-GCM. Here is why:
- Parallel Processing (Speed): GCM can encrypt multiple parts of your file at the same time (using your device's multi-core processor). This makes TaskNote feel instant, even with large notes.
- Authentication (Integrity): GCM includes a built-in check. If a hacker intercepts your encrypted note and changes one single bit (trying to corrupt it or inject code), AES-GCM will detect the tampering immediately and refuse to decrypt it.
🛡️ AES in TaskNote
We implement AES-256-GCM via the Web Crypto API.
This means we don't run slow Javascript code to encrypt your data. We use the native cryptography engine built directly into your browser (Chrome, Firefox, Safari).
- It is hardware-accelerated.
- It is vetted by security experts from Google and Mozilla.
- It happens entirely on your device (Client-Side).
❓ Frequently Asked Questions (FAQ)
Can quantum computers crack AES-256?
Currently, no. While quantum computers threaten some types of encryption (like RSA), AES-256 is considered "Quantum Resistant." Experts believe 256-bit keys will remain secure for decades to come.
Is AES-256 slower than AES-128?
Technically yes, about 20-40% slower, but on modern processors, this difference is measured in nanoseconds. You will never feel the difference in TaskNote, so we chose the maximum security of 256-bit.
Does TaskNote invented its own encryption?
Never. "Rolling your own crypto" is rule #1 of what NOT to do in security. We strictly use standard, audited implementations of AES-256-GCM provided by the browser environment.