DFINITY Foundation

ICDevs.org

CryptoIsGood

Anvil

ICPL.app

ysyms

The Accumulators’ Neuron

RawTech Venture

Paul Young

ICPMANUAL

8yeargangDAO

Isaac Valadez

Krzysztof Żelazko

Nicolas.ic

Smaug’s Neuron for Retail Investors

Internet Computer Association

Synapse.vote (formerly ICP Maximalist Network)

Arthur’s Neuron (used to be cycle_dao)

Inactive (Request Removal) - The Fools' Court

Always Rejects

John Wiegley

Create Low-Node and Geographically Grouped Subnets for Real-Time Multiplayer Game Canisters



## Who I Am

We are PLETHORA (@PlethoraGame), a fully on-chain digital society of games where composable social interactions can flourish through the permissionless magic of smart contract technology.

Tommy, co-founder of PLETHORA is submitting this proposal. You can verify this with his Twitter: @tommyinvests

## Objective

This is a governance motion proposal describing a solution for efficiently running a real-time game server using canisters. The team of PLETHORA proposes that the NNS should create **low-node subnets geographically grouped in certain regions of the world and that are specifically designated for real-time multiplayer game canisters and other low-latency dapps**. These subnets would consist of either **1 node** or **4 nodes** rather than the usual 13 node application subnets.

The power of composability will be unleashed when thousands of on-chain games are leveraging the same smart contract standards. We believe this is the first step in this direction.

This is a motion proposal and does not directly result in changes to the IC. Rather, voting to support the proposal is an indication that work should begin on creating these geo-located low-node subnets. If it passes, then we will work with DFINITY and other parties to create the 1-node or 4-node subnets.

## Background

In order to have a multiplayer game with real-time player movement, it is necessary to have a server that records the positioning of each player. This data needs to be updated frequently in order to prevent lagging of players. In most online games, this requires a ping of <100ms.

PLETHORA is focused on building 100% on-chain games, meaning we’ve built a real-time multiplayer server in a canister.

**And we made a video to show it to you.**

In this video:

* Every 300ms each player updates their position in the world to the canister
* Every 25ms each player queries the canister for positions of other players in the world
* We then estimate the animation states and use smoothing techniques to render the characters running/jumping around the 3D world

Here’s the link to the video demo:

https://youtu.be/FhBDi-mLMKs

However, we’ve ran into two main issues:

1. Canisters have >2000ms ping because canister state changes must go through consensus. The more nodes in a subnet, the longer it takes to reach consensus. This is awful lag for real-time multiplayer.
2. Two canister update calls are sent per second per player to record player positions. This huge volume of calls cost an exorbitant amount of cycles. The more nodes in a subnet, the more expensive the update calls become.

By lowering the amount of nodes in a subnet, we can reduce both latency and cost for running a real-time multiplayer game canister.

Another consideration we want to propose is creating **low-node subnets with nodes grouped in different regions of the world**. We propose creating low-node subnets specifically in North America, Europe, and Asia. Therefore, we could route our Western players to the North America/Europe subnets and our Eastern players to the Asia subnet. This will result in much lower latency from the game client to subnet, but also lower latency between the subnet nodes communicating for consensus.

_____


**But what about the security of these subnets?**

In its first iteration, the movement in PLETHORA’s games will be client-authoritative, meaning it is purely for visual purposes. For this reason, it’s not a major concern that a subnet could be subverted by two colluding nodes. There’s no incentive to do so because the multiplayer movement does not have important game logic associated with it. For this first stage, we believe 1-node subnets in North America, Europe, and Asia are sufficient.

In the future, we may add smart contract rules that enforce movement constraints. Thus, we could have smart-contract-authoritative movement, and players could be rewarded by smart contract logic based on their position in a world. At that point in time, the security of the subnet may become a bigger concern. In this stage, we believe 4-node subnets in North America, Europe, and Asia are sufficient.

We have designed our fully on-chain games to balance security and latency. High-value game/player data is stored on secure 13-node subnets. The game canisters in the 13-node subnets can query the canisters in low-node subnets to read data and make decisions.

## Why This Is Important

Gaming will be the next major use case of crypto, and gaming economies will eventually overtake economies of entire countries. We have conviction that in order to build games that will rise to that scale, everything needs to be fully on-chain. When a game is fully enforced by smart contracts, it presents the greatest opportunity for humanity to improve how we interact and create value for each other.

And when we say 100% on-chain, we mean it. This includes real-time multiplayer game servers. Adhering closely to this strict standard will enable composability like never before, and will empower games to be DAO-governed through the SNS.

No other blockchain can run a complex game with tremendous amounts of logic and data 100% executed and stored on-chain. We need to show the world what the Internet Computer is capable of accomplishing.

## What We Are Asking The Community

Provide feedback on this proposal within this thread.

Vote accept or reject on NNS Motion

Participate in technical discussions as the motion moves forward

## Additional Cycle Costs Calculations

Let’s calculate the cost savings of switching to a 4-node subnet. These are just estimates, the actual amounts will vary depending on how many bytes are sent in the ingress messages.

If we send 2 update calls per second per player, that’s roughly 7.2K update calls per hour.

On a 13-node subnet, 7.2K update calls with position/rotation/scale/animation data uses roughly 19B cycles.

Let’s assume we have 10,000 concurrent players for 24 hours on a 13-node subnet.

On a **13-node subnet**, it would cost around 3400T cycles.
That’s roughly **$4,530 per day or $136,000 per month**

If we do the same math for a **4-node subnet**, it would cost around 1046T cycles.
That’s roughly **$1415 per day or $42,433 per month**

If we do the same math for a **1-node subnet**, it would cost around 262T cycles.
That’s roughly **$354 per day or $10,629 per month**

As you can see, the cost of cycles is significantly reduced with less nodes. This will become increasingly important as games scale to millions of users.

It’s harder to calculate latency when reducing the node count of a subnet, but we expect it will **significantly** decrease as well.

## Forum Post

Developer forum: https://forum.dfinity.org/t/proposal-create-a-3-node-subnet-for-real-time-multiplayer-game-canisters/19612



Low-Node Subnets for Real-Time Multiplayer Game Canisters