BACnet.Protocol.AddressBinding (bacstack v0.1.0-dev.1)

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An Address Binding is the mapping between a device's Object Identifier (the Device object instance) and the network address at which that device can be reached. It is the fundamental data structure used by the BACnet address resolution mechanisms.

Every BACnet device maintains a Device Address Binding table. Static bindings can be configured locally or via the Write Property service. Dynamic bindings are learned automatically when a device receives an I-Am message (in response to Who-Is) or when it receives traffic from a previously unknown device. Foreign devices registered through a BBMD also appear in address binding tables.

The structure is used in the Device object's Device_Address_Binding property, in the recipient fields of event and COV subscriptions, in the destination lists of the Write Group service, and in many network-layer and application- layer routing decisions. Correct maintenance of address bindings is essential for reliable communication across BACnet/IP, BACnet/Ethernet, and MS/TP networks that are joined by routers.

Examples (Doc Test)

iex> binding = %AddressBinding{
...>   device_identifier: %ObjectIdentifier{type: :device, instance: 123},
...>   network: 0,
...>   address: <<192, 168, 1, 100, 0xBA, 0xC0>>
...> }
iex> binding.device_identifier.instance
123

Summary

Types

t()

Associates a BACnet device object identifier with its network address.

Functions

encode(access_spec, opts \\ [])

Encodes a BACnet address binding into BACnet application tags encoding.

parse(tags)

Parses a BACnet address binding from BACnet application tags encoding.

valid?(t)

Validates whether the given address binding is in form valid.

Types

t()

@type t() :: %BACnet.Protocol.AddressBinding{
  address: binary(),
  device_identifier: BACnet.Protocol.ObjectIdentifier.t(),
  network: BACnet.Protocol.NetworkLayerProtocolMessage.dnet()
}

Associates a BACnet device object identifier with its network address.

Functions

encode(access_spec, opts \\ [])

@spec encode(t(), Keyword.t()) ::
  {:ok, BACnet.Protocol.ApplicationTags.encoding_list()} | {:error, term()}

Encodes a BACnet address binding into BACnet application tags encoding.

parse(tags)

@spec parse(BACnet.Protocol.ApplicationTags.encoding_list()) ::
  {:ok, {t(), rest :: BACnet.Protocol.ApplicationTags.encoding_list()}}
  | {:error, term()}

Parses a BACnet address binding from BACnet application tags encoding.

valid?(t)

@spec valid?(t()) :: boolean()

Validates whether the given address binding is in form valid.

It only validates the struct is valid as per type specification.