Why Avalanche

talk.gyuho.dev/why-avalanche-2023q2.html

Who am I?

이규호 (Gyuho Lee)
Protocol Engineer, Ava Labs
github.com/gyuho
linkedin.com/in/gyuho
twitter.com/gyuhox
t.me/leegyuho (Telegram)

Web3 needs...

Decentralization: Network of millions of nodes
Scalability: Consensus of sub-second finality
Customization: Support app-specific chain

News

Yes! Avalanche solves "scalability", while "decentralized" with novel consensus algorithm and "customizable" with subnets.

Agenda

What is Avalanche? (Overview)
Avalanche Consensus (Snowman)
Avalanche Subnet
Avalanche vs. Others
FAQs
Q&As

What is Avalanche?

Overview

What sets Avalanche apart?

"The fact that it works, it's fast, it scales, can grow and absorb any use case, can be used for compliant asset offerings. Bitcoin is single asset, single chain. Ethereum is multi-asset, single chain. Avalanche is multi-asset, multi-chain system. Most decentralized with fastest consensus finality."

All Access with Emin Gün Sirer - Ep. 51 (2023)

Avalanche ($AVAX)

Mainnet launched in Sep 2020
Supports Ethereum Virtual Machine (EVM)
Novel Consensus Algorithm: Snowman
Proof-of-Stake
Fast and Scalable L1 (>6K EVM TPS)
Reliable (no downtime, no reorg)
Platform for deploying "Subnets"

Avalanche Today

>3.6B requests (a day, July 2022) with ~80ms latency

Avalanche Today

Subnet effect -- scales without congestion

Avalanche Today

DFK subnet using more gas than Polygon and BNB

DFK subnet == Over 200-million requests per day

Avalanche Today

Subnet horizontally scales!

>800 TPS (possible >6,000 TPS)

Avalanche TPS

Customize subnet-evm for super-high TPS (>6K)

Different gas limit than primary network

Avalanche TPS

Build custom VM for high TPS workloads (>44K)

Possible with Avalanche Consensus + Subnets

Consensus with sub-second finality (Fast)
Decentralized with >1,200 validators (Secure)
Subnets for application specific chains (Isolation)

Avalanche Consensus ☃️

Snowman Protocol

Consensus

"Assume a collection of processes that can propose values. A consensus algorithm ensures that a single one among the proposed values is chosen." Leslie Lamport, Paxos Made Simple (2001)

Should this transaction be placed in a block or not?

PoW or PoS is NOT a consensus mechanism!

Consensus Until Now

Classical (Lamport 1998, Paxos/Raft/etcd)

Quick finality but does not scale
Quadratic message complexity
Permissioned, requires precise membership

Consensus Until Now

Nakamoto (Bitcoin 2008)

Robust, no need for precise membership
High latency, low throughput
Wastes energy, not green, not sustainable

Consensus Until Now

PBFT (1999)

Powers many PoS networks (Tendermint, Casper)
Committee/leader-based

Can't scale easily ("leader/coordinator" dilemma)
Quorum-based: must know all participants
Fast when membership is small

Deterministic safety (100% safe)

Hard limit on the Byzantine adversaries

Many are very complicated

Avalanche Consensus Family

Published in 2020
Instant finality, low latency (~1 sec)
High throughput (>6,000 TPS)
Scales >10-million nodes
Robust, no need for precise membership
Leaderless
Quiescent, green, sustainable
Inspired by epidemic protocols and gossip networks
New idea: deliberately metastable

Avalanche Sustainability

Binary Consensus

Pick one red/blue -- no correct answer
Adopt the majority color by repeated sub-sampling
Consensus results in the entire network agreeing on either red or blue
Even with 50/50 split, random perturbation in the sampling results in a single value being selected

At the beginning, pick any color (no correct answer)

Radomly sub-sample the network

"Red" is the majority from the sample

Adopt the majority color, "red"

Repeat this random sampling in parallel, in all nodes

Repeated random sampling perturbs conflicting state

Sequence of metastable process of random sampling

All converge to the same value (agreement)

"The protocol is designed to tip" (YouTube)

Fast Finality

Avalanche == no block re-org, no longest chain rule

Re-org in game? May lose item after tx revert
Re-org in bridge? Must wait longer for source chain
Re-org in payment? May lose money for goods

Avalanche Subnet 🔺

What is Subnet?

Primary Network == Special Subnet

X-chain for fast asset exchange
P-chain coordinates validators and subnets
C-chain executes EVM contracts with ETH RPCs

Subnet validator must validate primary network!

Subnet == Sub-network

Subnets == Functional sharding

Subnet is a functional sharding!

Subnets == Failure isolation

Failure in one subnet does not impact the other!

Thus better fault tolerance and better reliability!

Subnets == Gas isolation

Gas-heavy app/game can launch in subnet!

Subnet has its own gas token!

Isolated gas consumption, thus no gas fee spikes

Isolated loads, thus better performance

Subnet (sub-network)

Custom networks running on Avalanche

Security: Choose who and how many can participate
Compliance: Comply with specific industry, jurisdiction, regulatory environment (KYC)
Custom Execution: Common VM (subnet-evm with custom gas token), custom VM optimized for own use case (key-value store, gaming, Rust 🦀)
Privacy: Controls data visibility (encryption)

Avalanche vs. Others

Avalanche validator set scales

No upper cap on consensus membership!

Possible thanks to novel consensus algorithm

Avalanche	Cosmos	Polygon	Klaytn	Hedera
>1,200^[1]	~200	~100^[2]	~30	26

[1] Theoretically, Avalanche can scale beyond millions.

[2] Sidechain on Ethereum.

Sidechain security

Avalanche	Polygon
L1 with own validator set (>1,200)	Sidechain (~100)

Polygon does not settle transactions on Ethereum, simply committing its state root on Ethereum. A sidechain does not leverage the security or decentralization of the base chain layer, since without a permissionless fraud challenger, the sidechain can checkpoint the arbitrary state root on Ethereum.