Blockchain Trilemma & Design Trade-offs
The blockchain trilemma suggests you can optimize only two of decentralization, security, and scalability at once. You'll learn how different chains prioritize and what that means for users.
Who Is This For?
- •Learners comparing chains like Ethereum, Solana, and Cosmos
- •Builders choosing infrastructure for their app
Learning Objectives
- 01Define each pillar of the trilemma
- 02Map real networks to their design choices
- 03Choose infrastructure that matches your risk and UX goals
The Three Pillars
Every blockchain must balance three fundamental properties. Optimizing for one often means compromising another. Understanding these trade-offs is key to evaluating any network.
Decentralization
Power distributed across many independent participants. No single entity controls the network.
- • Many validators worldwide
- • Low hardware requirements
- • Censorship resistance
- • No single point of failure
Security
Resistance to attacks and manipulation. Economic guarantees make cheating unprofitable.
- • Attack costs exceed rewards
- • Immutable transaction history
- • Robust consensus mechanism
- • Battle-tested over time
Scalability
Ability to handle many transactions quickly and cheaply as usage grows.
- • High transactions per second
- • Low latency confirmations
- • Affordable fees at scale
- • Good user experience
Try It: Adjust Priorities
Drag the sliders to set your priorities. Watch how increasing one forces others to decrease— that's the trilemma in action!
Network Examples
Different chains make different bets on the trilemma. Let's compare how major networks position themselves.
Ethereum
Maximum decentralization and security, uses L2s for scale
Quick Comparison
| Chain | Decent. | Security | Scale | Trade-off |
|---|---|---|---|---|
| Ξ Ethereum | 90 | 95 | 30 | Rollup-centric roadmap |
| ◎ Solana | 50 | 70 | 95 | Monolithic high-performance |
| ₿ Bitcoin | 95 | 100 | 15 | Security-first, Lightning for scale |
| ⚛ Cosmos | 70 | 75 | 80 | App-specific chains |
| ⬡ Polygon PoS | 55 | 65 | 85 | Sidechain + zkEVM development |
| 🔺 Avalanche | 75 | 80 | 75 | Subnets for app chains |
Application Alignment
Different applications have different needs. The right infrastructure depends on what you're building and what trade-offs are acceptable.
Use Case Explorer
Click a use case to see which priorities matter most and what infrastructure fits.
Hybrid Approaches
Many projects use layered architectures to get the best of multiple worlds:
L1 + L2 Strategy
Use Ethereum L1 for high-value operations (treasury, staking) and L2s for frequent user interactions (trading, gaming).
App Chains
Build your own chain (Cosmos, Avalanche subnet) for full control over parameters, then bridge to larger ecosystems for liquidity.
Common Mistakes & Gotchas
These misconceptions about blockchain trade-offs lead to poor infrastructure choices.
Pro tip: When evaluating a chain, look at validator requirements (can a regular person run one?), geographic distribution, and who controls governance—not just headline TPS numbers.
Knowledge Check
Let's see how well you understand the blockchain trilemma. Answer all 5 questions below.
What are the three pillars in the blockchain trilemma?
Which pillar do rollups primarily improve for Ethereum?
Why might a game choose an appchain?
Which chain prioritizes security and decentralization over scalability?
What’s a key consideration when evaluating a chain’s decentralization?