A pure Swift implementation of IEEE 1722.1-2021 (ATDECC, formerly AVDECC) and the Milan Vendor Unique extensions, sending and receiving PDUs directly on raw Ethernet.

ATDECCSwift was previously AVDECCSwift, a wrapper around the L-Acoustics la_avdecc C++ library. It no longer depends on la_avdecc, although its wire behaviour (timeouts, retries, tolerance of non-conforming entities, which responses raise notifications) deliberately matches it.

• Linux only. Frames are sent and received with io_uring (IORingSwift), on AF_PACKET sockets or serial devices.
• ATDECC Controller role. The codecs encode and decode commands and responses in both directions, so an entity (talker/listener) responder can be added later.
• Swift 6 strict concurrency: EndStation and Controller are actors.

import ATDECC

let endStation = try EndStation(port: EthernetPort(interfaceName: "eth0"))
let controller = try await Controller(
  endStation: endStation,
  entityID: endStation.makeDynamicEntityID()
)

for await event in await controller.events() {
  if case let .entityOnline(id) = event {
    let descriptor = try await controller.readEntityDescriptor(id: id)
    print(descriptor.entityName)
  }
}

See Examples/Discovery/Discovery.swift for a complete, runnable example.

The names follow IEEE 1722.1-2021:

• NetworkPort — a protocol for the link AVTP frames travel on. EthernetPort joins the AVDECC multicast groups (rather than going promiscuous, so it works behind bridges that filter multicast in hardware); SerialPort reaches a single entity over a UART; and VirtualPort connects ports on an in-memory VirtualNetwork for tests and simulation.
• EndStation<Port> — an ATDECC End Station: owns a port, dispatches received PDUs to its entities, and issues dynamic entity IDs.
• Controller<Port> — an ATDECC Controller entity. It runs a Discovery state machine, the AEM and ACMP controller state machines (250 ms AECP timeout with one retry and IN_PROGRESS handling, per-command ACMP timeouts from Table 8-1), and reports discovery, unsolicited notifications and sniffed ACMP traffic as ControllerEvents.
• Codecs — AvdeccPdu (Adpdu, Aecpdu, Acmpdu), AemCommandPayload / AemResponsePayload, MvuCommandPayload / MvuResponsePayload and Descriptor are enums parsed with swift-binary-parsing and serialized with the SerDes protocols from IEEE802Swift.

Controllers and end stations are generic over their port type, so frames are handled without existential dispatch.

Requires Swift 6.2 or later on Linux, with liburing and, for link state monitoring through NetLinkSwift, libnl installed:

apt install liburing-dev pkg-config libnl-3-dev libnl-route-3-dev libnl-nf-3-dev libnl-genl-3-dev \
  libmnl-dev libnftnl-dev

swift build
swift test

The tests run controllers against a simulated entity on a VirtualNetwork and need no network access or privileges. The serial port tests use a pseudo-terminal and io_uring, which Docker's default seccomp profile blocks: run a container with --security-opt seccomp=unconfined.

Sending and receiving raw Ethernet needs CAP_NET_RAW. Either run as root, or grant the capability to the binary:

sudo setcap cap_net_raw+ep .build/debug/avdecc-discovery
.build/debug/avdecc-discovery eth0

SerialPort carries ATDECC over a point-to-point UART, as used between a host and an AVB entity's firmware. Each AVTPDU (the AVTP control header and its ADP, AECP or ACMP data, with no Ethernet header or padding) is COBS encoded and sent between zero bytes. The device is set to raw 8N1 at the requested baud rate (115200 by default).

The wire carries no addresses. Every frame goes to the one peer, and received frames appear to come from SerialPortPeerMacAddress. The host end uses SerialPortLocalMacAddress (0A:E9:1B:00:00:00) by default, because the entity firmware sends frames addressed to it, and all multicast frames, to its UART.

.build/debug/avdecc-discovery /dev/ttyAMA0@115200

Apache License 2.0; see LICENSE.