SAM v2

Deprecated: SAM v2 shipped with I2P 0.6.1.31 and is no longer maintained. Use SAM v3 for new development. v2’s only improvement over v1 was support for multiple sockets multiplexed over a single SAM connection.

Version Notes

• Reported version string remains "2.0".
• Since 0.9.14 the HELLO VERSION message accepts single-digit MIN/MAX values and the MIN parameter is optional.
• DEST GENERATE supports SIGNATURE_TYPE so Ed25519 destinations can be created.

Session Basics

SESSION CREATE STYLE={STREAM|DATAGRAM|RAW} DESTINATION={name|TRANSIENT} [DIRECTION={BOTH|RECEIVE|CREATE}] [option=value]

• Each destination may have only one active SAM session (streams, datagrams, or raw).
• STYLE selects virtual streams, signed datagrams, or raw datagrams.
• Additional options are passed to I2CP (for example, tunnels.quantityInbound=3).
• Responses mirror v1: SESSION STATUS RESULT=OK|DUPLICATED_DEST|I2P_ERROR|INVALID_KEY.

Message Encoding

Line-oriented ASCII with key=value pairs separated by spaces (values may be quoted). Communication types are the same as v1:

• Streams via the I2P streaming library
• Repliable datagrams (PROTO_DATAGRAM)
• Raw datagrams (PROTO_DATAGRAM_RAW)

When to Use

Only for legacy clients that cannot migrate. SAM v3 offers:

• Binary destination handoff (DEST GENERATE BASE64)
• Subsessions and DHT support (v3.3)
• Better error reporting and option negotiation

Refer to:

• SAM v1
• SAM v3
• Datagram API
• Streaming Protocol