Complete Guide to Private Transactions For Businesses & Individuals
Learn how to protect your financial privacy on Solana. Step-by-step tutorials, real examples, and best practices.
APP SENTINEL
NETWORK SOLANA
UPDATED 16 FEB 2026
SECTION 01
What is Sentinel?
Sentinel is a privacy application built on Solana that allows you to send and receive funds without revealing amounts or identities to the public.
It is built for institutional-grade operations: controlled access, cryptographic integrity, and selective disclosure workflows for compliance teams.
Unlike regular Solana transactions where everything is visible on-chain, Sentinel uses encrypted vaults and Zero-Knowledge proofs to keep your financial activity private.
🔒
PRIVATE
Amounts and recipients are encrypted. Only you can see your vault balance and transaction history.
⚡
FAST & CHEAP
Built on Solana. Transactions complete in 1-2 seconds for $0.01-0.05 in fees.
🛡️
SECURE
Zero-Knowledge cryptography ensures privacy without compromising security or verifiability.
✓
COMPLIANT
Not a mixer. Individual vaults allow for selective disclosure and audit trails when needed.
FEATURE
REGULAR SOLANA
SENTINEL
Transaction amount
Public ❌
Private ✓
Recipient address
Public ❌
Private ✓
Wallet balance
Public ❌
Private ✓
Transaction speed
1-2 seconds ✓
1-2 seconds ✓
Transaction cost
$0.01 ✓
$0.01-0.05 ✓
Self-custody
Yes ✓
Yes ✓
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SECTION 02
How It Works
PRIVACY FLOW
Your vault is like an encrypted safe on the blockchain. When you deposit funds, they enter the vault. All transfers between vaults are private. When you withdraw, funds leave the vault.
🔐
ENCRYPTED BALANCE
Your balance is stored as a 64-byte encrypted ciphertext using ElGamal encryption. Only your private key can decrypt it.
🔑
YOUR KEYS = YOUR ACCESS
No password recovery, no "forgot password". If you lose your wallet's seed phrase, you lose access to your vault forever.
📊
COMMITMENT PROOFS
Deposits/withdrawals use Zero-Knowledge proofs to verify amounts are correct without revealing the actual values.
🔄
NO MIDDLEMAN
Sentinel operators cannot see balances, freeze funds, or block transactions. It's a smart contract — code, not people.
Important: The initial deposit and final withdrawal are visible on-chain (like any Solana transaction). Everything that happens INSIDE your vault is private.
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SECTION 03
Getting Started
1
CONNECT YOUR WALLET
Open Sentinel and connect your Solana wallet (Phantom, Solflare, etc.). Make sure you're on the correct network (mainnet or devnet). You will need a small amount of NORTH tokens to create your rail (one-time).
2
SETUP — THREE STEPS
In the Setup section, complete in order: (1) Privacy Rail — Initialize your on-chain identity (requires NORTH); (2) ZK Vault — Initialize your encrypted balance container; (3) Handshake — Create a handshake so you can deposit from your wallet. Each step is one-time.
3
DEPOSIT FUNDS
Transfer SOL or SPL tokens (e.g. USDC) from your wallet into your Sentinel vault. This transaction is visible on-chain.
4
USE PRIVATE TRANSFERS
Send funds to other users by entering their Rail address. Amounts and balances stay private. To receive a transfer without having deposited first, click Prepare to receive in the Vault section once — then share your Rail address with the sender.
5
WITHDRAW WHEN NEEDED
Withdraw funds from your vault back to your regular wallet anytime. This transaction is visible on-chain.
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SECTION 03.5
Reading Your Vault Balance
Your vault balance is encrypted on-chain. Only you can decrypt it with your wallet. In the Sentinel app, your Private Balance is shown automatically in the Vault section — it updates as you deposit, receive transfers, or withdraw. Decryption happens locally in your browser; no server sees your balance.
Privacy Note: If someone has access to your unlocked wallet, they can decrypt your vault balance. Always lock your wallet when not in use.
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SECTION 04
Who Uses Sentinel? Real Examples
Sentinel is used by businesses, traders, institutions and individuals who need financial privacy. Here are concrete examples:
🏢 BUSINESS OWNER — IMPORT/EXPORT
Sophie, 42 · Textile SME · $5M revenue
USE CASE
Sophie buys textiles from China and pays in USDC. She uses Sentinel to prevent competitors from analyzing her blockchain transactions and identifying her suppliers.
HOW SHE USES IT
Deposits $200k in her Sentinel vault monthly
Pays each supplier privately from vault to vault
Competitors cannot see amounts or recipients
Maintains competitive advantage on supply chain
RESULT
Supply chain protected · Better negotiation · Instant payments · 90% lower fees vs SWIFT
💼 INVESTMENT FUND — VENTURE CAPITAL
Marc, 38 · Crypto fund · $50M AUM
USE CASE
Marc invests in early-stage tokens. Without Sentinel, other funds see his purchases on-chain and copy his positions, driving up prices before he's done accumulating.
Innovation Director · Regional bank · 2000 B2B clients
USE CASE
The bank wants to offer instant, cheap payments to Asia for business clients. But public Solana transactions would violate banking secrecy and expose client financial strategies.
HOW THEY USE IT
Creates institutional Sentinel vault with $10M liquidity
Each business client gets a sub-vault
International payments go vault-to-vault (private)
Amounts and recipients remain confidential
Can produce compliance reports without public exposure
Karim does arbitrage between crypto exchanges. MEV bots scan the mempool, see his transactions, and front-run his trades, eliminating his profit.
HOW HE USES IT
Keeps trading capital in Sentinel vault
Maintains vaults on each exchange platform
Transfers funds privately between exchange vaults
MEV bots cannot see his movements
Captures full arbitrage spread
RESULT
Zero front-running · +0.5-1% per trade recovered · Strategy remains private · Profitability restored
👤 INDIVIDUAL — CRYPTO SALARY
Julie, 26 · Remote developer · $80k/year in USDC
USE CASE
Julie receives her salary in USDC on Solana. All her transactions are public: colleagues can see her exact salary, family tracks her spending, friends know her savings.
HOW SHE USES IT
Employer deposits salary directly to her Sentinel vault
All daily spending comes from vault (stays private)
No one can see her salary amount or expenses
She controls what financial info to reveal
RESULT
Financial privacy restored · Can use crypto daily without surveillance · Personal security improved
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SECTION 05
Understanding Privacy Levels
Sentinel's privacy improves with network activity. The more users and transactions, the harder it becomes to trace individual flows.
NETWORK SIZE
TRANSACTIONS/DAY
PRIVACY LEVEL
TRACEABILITY
Early (1-10 users)
< 50
Low (30%)
Possible with analysis
Growing (100-1000 users)
500-5000
Medium (60%)
Difficult
Mature (10000+ users)
50000+
High (90%+)
Nearly impossible
"With thousands of users and tens of thousands of daily transactions, tracing individual flows becomes practically impossible, even with sophisticated chain analysis."
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SECTION 05.5
What Sentinel CAN'T Hide (Important Limits)
Sentinel provides strong privacy, but it's not magic. Here's what remains visible on-chain:
👁️
VISIBLE: DEPOSIT/WITHDRAW
When you deposit or withdraw, the transaction is public. Anyone can see: wallet address, timestamp, and amount going in/out of the vault.
🕐
VISIBLE: TIMING
Transaction timestamps are public. If you deposit and immediately withdraw the same amount, this pattern is visible (though recipients aren't).
🌐
VISIBLE: IP ADDRESS
Your ISP and RPC provider can see your IP when you transact. Use a VPN if this is a concern for your threat model.
🔍
VISIBLE: VAULT CREATION
Creating a vault is a public transaction linked to your wallet. If someone knows your wallet, they know you have a Sentinel vault (but not the balance).
Key Insight: Sentinel hides WHO you pay, HOW MUCH, and your BALANCE. It does NOT hide THAT you're using Sentinel or WHEN you transact. Adjust your expectations accordingly.
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SECTION 06
Security Best Practices
🔐
WALLET SECURITY
Use a hardware wallet for large amounts. Never share your seed phrase. Enable all available security features on your wallet.
⏱️
TIMING
Wait before withdrawing after deposit. Immediate deposit-withdraw patterns are easier to link. Let funds sit for days/weeks.
💰
AMOUNTS
Avoid unique round numbers. $1,234.56 is easier to track than $1,000. Vary your transaction amounts.
🔄
OPERATIONAL SEGREGATION
Separate treasury, payroll, and vendor flows with dedicated vault operations to reduce operational risk and simplify reviews.
👥
NETWORK EFFECT
Privacy improves as more people use Sentinel. Encourage others to adopt it for everyone's benefit.
⚖️
COMPLIANCE EVIDENCE
Prepare selective disclosure packages from your private records to support audits, legal requests, and internal controls without exposing full activity.
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SECTION 07
Frequently Asked Questions
Is Sentinel a mixer like Tornado Cash?
No. Mixers pool everyone's funds together. Sentinel gives each user their own encrypted vault. Your funds never mix with others. This makes it legal, compliant, and safer.
Can I lose my funds if the vault gets hacked?
Your vault is controlled by your wallet's private keys. Only you can withdraw. The encryption ensures no one else can see or access your balance. Standard wallet security rules apply.
What if I need to prove where funds came from?
You hold the private keys that can decrypt your vault's history. You can selectively disclose transaction details to auditors or regulators if legally required, without making everything public.
How much does it cost to use?
Transactions cost the same as regular Solana transactions (~$0.01-0.05). There are no additional protocol fees. You only pay standard Solana gas fees.
What tokens can I use?
SOL and SPL tokens (e.g. USDC) are supported. You can deposit and withdraw any supported SPL token by entering its mint address in the app.
Is this really private if deposit/withdraw are visible?
Yes. While deposit and withdrawal endpoints are visible (like any blockchain transaction), everything in between is encrypted. With many users, linking a specific deposit to a specific withdrawal becomes nearly impossible.
Can institutions use Sentinel without breaking compliance obligations?
Yes. Sentinel combines private vault operations with explicit rail controls, deterministic account governance, and selective disclosure support for regulated reporting workflows.
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SECTION 08
Ready to Get Started?
Open the Sentinel app and create your encrypted vault in minutes.
Disclaimer: Sentinel is experimental software. Use at your own risk. Always start with small amounts. Not financial or legal advice. Consult professionals for your specific situation.