Jockey Peer Interface (PI) Design

Peer Interface (PI) API

The peer interface (PI) API is intended to provide an application developer with a view into a peer network. This API is as minimal as possible, since it is provided as an interface between an application running as a process and the Jockey engine, which runs as a separate process, once per machine. Implementations of The PI API must perform the interprocess communication (IPC) between the application and engine. The initial implementation will perform the IPC by implementing the PI API as a shared library or DLL, which can be invoked from multiple applications, but will make calls upon a single instance of the Jockey engine.

The first section of the API provides calls for the application to begin a new peer session, end an existing peer session, and query for status of the peer network and the peer identity.

PeerPlatform	Related Classes
Primary entry point for an application. Allow users to create and end application sessions. Allow addition and removal of identities and permission sets.	PlatformInfo

PlatformInfo	Related Classes
Provide information about peer networks installed and/or active. Provide status information about engine.	PeerPlatform

DeviceDescriptor	Related Classes
Provide information about the hardware, network connectivity, and identification of a peer machine.	PeerToken

PeerToken	Related Classes
Describe a specific instance of a peer computing device. Act as a shallow identifying token for a peer reachable through the peer network.	DeviceDescriptor

AppDescriptor	Related Classes
Provide information about a peer enabled software application.	PeerPlatform

Authority	Related Classes
Represents an entity which may have some specific permissions on the peer network. Provides a security context for an application, either based on the application itself, the person using the application, or the current role of the application.	Credential

Credential	Related Classes
Act as a piece of identifying information about an authority.	Authority

The objects depicted below provide an interface for a user application to launch searches of the peer network, in order to find neighboring peers, peer groups, and services.

PeerGroupToken	Related Classes
Describe a specific instance of a peer network group. Act as a shallow identifying token for a real peer group known to the peer network implementation.	PeerGroupToken PeerGroupDescriptor PeerNetwork

PeerGroupDescriptor	Related Classes
Provide identifying information about a peer group.	PeerGroupToken PeerNetwork

PeerNetwork	Related Classes
Uniquely identify a peer network implementation for application purposes.

PeerNetworkBrowser	Related Classes
Enable an application to locate other peers and groups Enable an application to perform group actions (create, delete, join, leave).

PeerNetworkListener	Related Classes
Called when peers and groups are discovered, discoveries are started, completed, or time out. Implemented by an application that expects to receive notifications from a directory.	PeerNetworkBrowser

FindMarker	Related Classes
Serves as a marker for a query currently in progress. Provides status detail for find progress.	PeerNetworkBrowser

The next set of objects enable an application to communicate with other applications through the peer network.

The communications subset of the PI API simplifies network communications for applications which desire to do the most common application messaging. The message handling system scopes all messages by peer network group; the application must go through extra steps to communicate with other applications outside of the application's current group.

This portions of the API relies on some assumptions about the communications available from the peer network. These assumptions are:

• Upon entering an peer network group, the peer begins listening for inbound messages from other peers in the group.
• Other peers act the same way, so that upon entering a group, an application can generate outbound messages that can reach any peer in the same group.

MessageBroker	Related Classes
Exchanges messages (fire-and-forget, requests, replies) with the peer network. Provides ability to communicate with any other peer in the same network that is a member of the same group.	MessageListener

MessageListener	Related Classes
Called to inform a receiver when a request or message has been received or cancelled. Called to inform a sender when a sent message has been delivered, cancelled, or a matching response received. Implemented by an application that expects to receive notifications about messages.

PeerMessage	Related Classes
Represents a message transmitted or received from the peer network. Identifies a message as an unsolicited message, a request, or a response.

SendMarker	Related Classes
Serves as a marker for a message send in progress. Provides status detail for sending progress.	PeerMessage

ReceiveMarker	Related Classes
Serves as a marker for a message being received. Provides status detail for receive progress.	PeerMessage

ResponseMarker	Related Classes
Serves as a marker for a message sent out on the peer network, and the resultant response that is expected. Provides status detail for request/response progress.	PeerMessage SendMarker