Interoperability & Bridges Overview | Asset Taxonomy

At a Glance

Bridges move assets across chains, enabling liquidity and app ecosystems to interconnect. You'll learn how wrapping works, why bridges are high-value targets, and safer ways to bridge.

Lock-and-MintLiquidity NetworksZK BridgesSafety

Who Is This For?

•Users moving tokens between chains
•Analysts evaluating cross-chain protocols

Learning Objectives

01Explain how token wrapping and lock-and-mint models operate
02Identify major risks in bridge design
03Choose safer bridging approaches for everyday use

Section 1

Why Interoperability Matters

Blockchains are isolated by design. Each chain has its own state, consensus, and tokens. But users and protocols need to move value between them.

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Cheaper Fees

Ethereum gas can be expensive. Users bridge to L2s (Arbitrum, Optimism, Base) for 10-100x cheaper transactions.

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Access New Apps

Some DeFi protocols, games, or NFTs only exist on specific chains. Bridging lets you participate in those ecosystems.

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Liquidity Expansion

Protocols need liquidity on multiple chains. Bridges allow capital to flow where yields or opportunities are best.

How Bridging Works (Step by Step)

Click through to see the lock-and-mint process:

Step 1: You Have ETH on Ethereum

You hold native ETH on Ethereum mainnet and want to use it on Arbitrum.

Origin Chain

Ethereum

Token

ETH

Amount: 1.0

In your wallet

Bridge

Waiting for deposit...

Destination Chain

Arbitrum

Token

—

Amount: —

Empty

Step 1 of 5

Section 2

Bridge Designs

Not all bridges work the same way. Each design makes different tradeoffs between speed, cost, and security.

Compare Bridge Designs

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Lock-and-Mint

Tokens are locked in a smart contract on the origin chain, and equivalent "wrapped" tokens are minted on the destination chain. To go back, wrapped tokens are burned and originals are released.

How It Works:

1

You send tokens to a smart contract on Chain A (locked)

2

Bridge validators confirm the deposit

3

An equal amount of wrapped tokens are minted on Chain B

4

To reverse: burn wrapped tokens on B, unlock originals on A

Examples:

Wormhole

Multi-chain bridge, supports 30+ chains

Portal (Wormhole)

Token and NFT bridging via Wormhole

Polygon PoS Bridge

Ethereum ↔ Polygon canonical bridge

Pros

✓ Conceptually simple
✓ Supports any token
✓ Well-established pattern
✓ Maintains 1:1 backing

Cons

✗ Wrapped tokens add complexity
✗ Smart contract risk (large TVL)
✗ Validator trust required
✗ Can be slow (waiting for finality)

Security

Trust bridge validators to correctly verify deposits

Speed

Minutes to hours (depends on finality)

Cost

Gas on both chains + bridge fee

Design Comparison

Design	Speed	Trust	You Receive
🔒 Lock-and-Mint	Slow-Medium	Validators	Wrapped tokens
💧 Liquidity Network	Fast	Economic	Native tokens
🔐 ZK / Light-Client	Medium	Math / proofs	Varies

Why Bridges Get Hacked

High-value targets: Bridges hold billions in locked tokens — a single exploit can drain enormous sums.

Complex attack surface: Cross-chain logic involves multiple chains, validators, and relayers — more points of failure.

Validator compromise: Compromised validators can mint unbacked tokens (see Ronin $625M, Wormhole $320M hacks).

Smart contract bugs: Bugs in lock/mint logic can let attackers withdraw more than deposited.

Section 3

Safety Checklist

Bridges carry real risk. Use this checklist every time you bridge tokens.

Pre-Bridge Safety Checklist

Check off each item before bridging:

Using official / canonical bridge URLcritical

Verify the URL matches the official project site. Bookmark it. Phishing bridges are common.

Sent a small test transaction firstcritical

Before bridging large amounts, send a tiny amount to confirm the route works correctly.

Checked audit history and past incidentshigh

Look for recent audits from reputable firms. Check if the bridge has been exploited before.

Reviewed TVL and bridge healthhigh

Higher TVL means more at stake (and more attractive to hackers). Very low TVL may indicate issues.

Not bridging during congestion or upgradesmedium

Network upgrades or high congestion can cause delays or failures. Check network status first.

Understand what I'm receiving (native vs wrapped)medium

Know if you'll get native tokens or wrapped versions. Wrapped tokens may need unwrapping later.

Safety Score:0/6 🚨 Complete checklist first

Which Bridge Should I Use?

Select your scenario for a recommendation:

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Casual User

Moving $50-500 for DeFi or NFTs

Recommended:

Liquidity network (Across, Hop)

Fast, cheap, get native tokens. Good UX for smaller amounts.

Alternative:

Canonical bridge if you can wait and want maximum security.

Watch Out

Common Mistakes & Gotchas

Bridging errors can mean lost funds. Avoid these costly mistakes:

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I Googled the bridge and clicked the first link

Phishing sites rank in search results. Always use bookmarked official links or navigate from the chain's docs page directly.

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I'll bridge my entire portfolio in one transaction

Always send a small test amount first. If something goes wrong, you lose $5 instead of $50,000.

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I received WETH — that's the same as ETH, right?

Wrapped tokens (WETH) represent ETH but aren't identical. Some protocols need native ETH. You may need to unwrap before using.

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The bridge is upgrading but my transaction is urgent

Never bridge during network upgrades or known maintenance windows. Transactions can get stuck or lost. Wait for stability.

⚠️ Golden Rule: If you're not sure about a bridge, use the chain's canonical (official) bridge. It's usually slower but carries the least additional trust assumptions.

Test Yourself

Knowledge Check

Let's see how well you understand blockchain bridges and interoperability.

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Part 3 Complete!

You've finished the DeFi Deep Dive. You now understand tokens, stablecoins, NFTs, tokenomics, and bridges.

✓ Token Types

✓ Stablecoins

✓ NFTs

✓ Tokenomics

✓ NFT Utility

✓ Bridges