Protocol Version Negotiation

Obsolete client

Note that all the bytes in the "Client sends" and "Server Sends" columns are hex-encoded.

Example protocol version negotiation with a client using an obsolete protocol version

Size (bytes)	Client sends	Server sends	Description
1	01		Client requests protocol version 1
1		02	Server rejects the request as it is lower than the minimum supported version
Communication ends and connection closes

Version unknown to the server

Note that all the bytes in the "Client sends" and "Server Sends" columns are hex-encoded.

Example protocol version negotiation with a client using protocol versions unknown to the server

Size (bytes)	Client sends	Server sends	Description
1	02		Client requests protocol version 2
2		03 01	Server indicates that version 2 is unknown, and the latest supported version of the server is version 1
1	00		Client rejects the offer to use version 1
Communication ends and connection closes

Successful version agreement

Note that all the bytes in the "Client sends" and "Server Sends" columns are hex-encoded.

Example protocol version negotiation successfully selecting a protocol version

Phase	Size (bytes)	Client sends	Server sends	Description
Negotiation	1	02		Client requests protocol version 2
	2		03 01	Server indicates that version 2 is unknown, and the latest supported version of the server is version 1
	1	01		Client accepts the offer to use version 1
Method selection	1	01		Client requests the get text method
	1		02	Server indicates that there is no text copied to the clipboard (No data)
Communication ends and connection closes