2.2.1 PowerShell Remoting Protocol Message

The structure of a PowerShell Remoting Protocol (PSRP) message is as follows.

Destination (4 bytes): The destination of this message.

Possible values.

Value	Meaning
0x00000001	The message is targeted to a client.
0x00000002	The message is targeted to a server.

MessageType (4 bytes): The type of message. The value of this field specifies what action MUST be taken by the client or server upon receipt. Possible values are listed in the following table.

Value	Meaning
SESSION_CAPABILITY 0x00010002	Session capability. Direction: Bidirectional (client to server or server to client). Target: RunspacePool.
INIT_RUNSPACEPOOL 0x00010004	Initialize RunspacePool. Direction: Client to server. Target: RunspacePool.
PUBLIC_KEY 0x00010005	Public key. Direction: Client to server. Target: RunspacePool.
ENCRYPTED_SESSION_KEY 0x00010006	Encrypted session key. Direction: Server to client. Target: RunspacePool.
PUBLIC_KEY_REQUEST 0x00010007	Public key request. Direction: Server to client. Target: RunspacePool.
CONNECT_RUNSPACEPOOL 0x00010008	Connect to a RunspacePool. Direction: Client to server. Target: RunspacePool.
RUNSPACEPOOL_INIT_DATA 0x0002100B	RunspacePool initialization data. Direction: Server to client. Target: RunspacePool.
RESET_RUNSPACE_STATE 0x0002100C	Reset RunspacePool Runspace state. Direction: Client to server. Target: RunspacePool.
SET_MAX_RUNSPACES 0x00021002	Set maximum runspaces in a RunspacePool. Direction: Client to server. Target: RunspacePool.
SET_MIN_RUNSPACES 0x00021003	Set minimum runspaces in a RunspacePool. Direction: Client to server. Target: RunspacePool.
RUNSPACE_AVAILABILITY 0x00021004	A response to either set maximum runspaces or set minimum runspaces in a RunspacePool or request for available runspaces in a RunspacePool. Direction: Server to client. Target: RunspacePool.
RUNSPACEPOOL_STATE 0x00021005	State information of a RunspacePool. Direction: Server to client. Target: RunspacePool.
CREATE_PIPELINE 0x00021006	Create a command pipeline and invoke it in the specified RunspacePool. Direction: Client to server. Target: RunspacePool.
GET_AVAILABLE_RUNSPACES 0x00021007	Get the number of available runspaces in a RunspacePool. Direction: Client to server. Target: RunspacePool.
USER_EVENT 0x00021008	Report a user-defined event from a remote runspace. Direction: Server to client. Target: RunspacePool.
APPLICATION_PRIVATE_DATA 0x00021009	Application private data: data private to the application using the PowerShell Remoting Protocol on the server and client, which is passed by the protocol without interpretation. Direction: Server to client. Target: RunspacePool.
GET_COMMAND_METADATA 0x0002100A	Get command metadata for commands available in a RunspacePool. Direction: Client to server. Target: RunspacePool.
RUNSPACEPOOL_HOST_CALL 0x00021100	Method call on the host associated with the RunspacePool on the server. Direction:  Server to client. Target: RunspacePool.
RUNSPACEPOOL_HOST_RESPONSE 0x00021101	Response from a host call executed on the client RunspacePool's host. Direction: Client to server. Target: RunspacePool.
PIPELINE_INPUT 0x00041002	Input to a command pipeline on the server. Direction: Client to server. Target: pipeline.
END_OF_PIPELINE_INPUT 0x00041003	Close the input collection for the command pipeline on the server. Direction: Client to server. Target: pipeline.
PIPELINE_OUTPUT 0x00041004	Output of a command pipeline on the server. Direction: Server to client. Target: pipeline.
ERROR_RECORD 0x00041005	Error record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
PIPELINE_STATE 0x00041006	State information of a command pipeline on the server. Direction: Server to client. Target: pipeline or RunspacePool.
DEBUG_RECORD 0x00041007	Debug record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
VERBOSE_RECORD 0x00041008	Verbose record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
WARNING_RECORD 0x00041009	Warning record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
PROGRESS_RECORD 0x00041010	Progress record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
INFORMATION_RECORD 0x00041011	Information record from a command pipeline on the server. Direction: Server to client. Target: pipeline.
PIPELINE_HOST_CALL 0x00041100	Method call on the host associated with the pipeline invocation settings on the server. Direction: Server to client. Target: pipeline.
PIPELINE_HOST_RESPONSE 0x00041101	Response from a host call executed on the client's host. Direction: Client to server. Target: pipeline.

RPID (16 bytes): A globally unique identifier (GUID) specifying the instance ID of the RunspacePool on the client.

PID (16 bytes): A GUID specifying the instance ID of the pipeline on the client.

Data (variable): The contents of this field are determined by the MessageType field, and are fully specified in section 2.2.2.