Session creation

High level flow of TrioSession

• Configure/Implement transport layer TrioNetworkClient
• Configure/Implement storage layer StorageClient
• Configure/Implement MessageSigner
• Create TrioSession
• Perform MPC actions

TrioSession is the main object which will be used to perform all of the MPC operations supported. To create TrioSession please follow the steps below.

Step 1 : Add library to your Project

---

• Create new xcode project if you haven't.

• Add SilentShard-Trio SDK using the instructions from the Installation Guide

Step 2 : Create new session

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• Import module - trioinitiator
• We can Create TrioSession by calling SilentShard.ECDSA.createTrioSession() or SilentShard.EdDSA.createTrioSession() (whichever applies) by providing the following parameters

1. Provide websocket client by using any of the below options :
   • Providing WebsocketConfig object to let SDK use default WebsocketClient i.e. TrioNetworkClient.
   • Providing custom TrioNetworkClient overriding(extending) TrioNetworkClient to override existing connect, read or write, etc. methods to add your own logic/configuration or additional process.
2. Provide cloud/server public key.
3. Provide storage client. (You need to implement the protocol StorageClient).
4. Provide message signer. (You need to implement the protocol MessageSigner).

Example

---

ECDSA

Example.swift

```swift showLineNumbers title="Example.swift"
import SwiftUI
import trioinitiator
import Combine

struct ContentView: View {

    var body: some View {
        VStack {
            
            let CLOUD_NODE_URI = "wss://trio-server.demo.silencelaboratories.com"
            
            //Other party verifying-key/public-key
            let cloudVerifyingKey = "9c4c79e942bbc3ff1d6ace7256404d701498056978cc4638c35832acdf821b1e"
            
            //Create websocketConfig to let SilentShard use default WebsocketClient.
            let websocketConfig = WebsocketConfig(
                url: CLOUD_NODE_URI,
            )
            
            //Create storage client instance to manage keyshare state
            let storageClient = CustomStorageClient()
            
            //Create duoSession

            /*
            We only have to pass websocketConfig which contains the server config and
            communication will be handled by internal websocketClient*/
            let duoSession = SilentShard.ECDSA.createTrioSession(
                messageSigner: TestECDSAMessageSigner(),
                cloudVerifyingKey: String(
                    cloudVerifyingKey
                ),
                websocketConfig: websocketConfig,
                storageClient: storageClient
)
            /*
            //or for EdDSA algorithm
            let duoSession = SilentShard.EdDSA.createDuoSession(
                messageSigner: TestECDSAMessageSigner(),
                cloudVerifyingKey: String(cloudVerifyingKey),
                websocketConfig: websocketConfig,
                storageClient: storageClient)
            */
            
        }
        .padding()
    }
}

#Preview {
    ContentView()
}

EdDSA

Example.swift

```swift showLineNumbers title="Example.swift"
import SwiftUI
import trioinitiator
import Combine

struct ContentView: View {

    var body: some View {
        VStack {
            
            let CLOUD_NODE_URI = "wss://trio-server.demo.silencelaboratories.com"
            
            //Other party verifying-key/public-key
            let cloudVerifyingKey = "9c4c79e942bbc3ff1d6ace7256404d701498056978cc4638c35832acdf821b1e"
            
            //Create websocketConfig to let SilentShard use default WebsocketClient.
            let websocketConfig = WebsocketConfig(
                url: CLOUD_NODE_URI,
            )
            
            //Create storage client instance to manage keyshare state
            let storageClient = CustomStorageClient()
            
            //Create duoSession

            /*
            We only have to pass websocketConfig which contains the server config and
            communication will be handled by internal websocketClient*/
            let duoSession = SilentShard.EdDSA.createTrioSession(
                messageSigner: TestEdDSAMessageSigner(),
                cloudVerifyingKey: String(
                    cloudVerifyingKey
                ),
                websocketConfig: websocketConfig,
                storageClient: storageClient
)
            /*
            //or for EdDSA algorithm
            let duoSession = SilentShard.EdDSA.createDuoSession(
                messageSigner: TestEdDSAMessageSigner(),
                cloudVerifyingKey: String(cloudVerifyingKey),
                websocketConfig: websocketConfig,
                storageClient: storageClient)
            */
            
        }
        .padding()
    }
}

#Preview {
    ContentView()
}

• CLOUD_NODE_URI is the URI of the cloud node.
• cloudPublicKey is the cloud verifying key (Ed25519 public key).
  • This public key is used to verify the server's signature on each message
  • See example here
• SilentShard Provides API for creating MPC TrioSession (Two-Party) using ECDSA algorithm.
• ECDSA Provides factory methods for creating MPC session using ECDSA algorithm.
• TrioSession Represents a two-party computation session that lets you perform MPC operations using SilentShard protocol.

You have now successfully set up the session and are ready to start performing MPC actions! 🎉