2.2.1 Structure of the Discovery Information Element
The structure of the discovery information element is shown in the following packet.
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Element ID |
Length |
OUI |
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... |
OUI Type |
Format identifier hash |
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Data (variable) |
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Element ID (1 byte): Contains the ID of the element as specified in [IEEE802.11-2007] section 7.3.2. It MUST contain a value of 221, identifying a vendor-specific element (as specified in [IEEE802.11-2007] table 26) in which the vendor is identified by an IEEE-issued OUI in a subsequent field.
Length (1 byte): Contains the length of the Data field in octets plus 8.
OUI (3 bytes): The IEEE-assigned OUI for Microsoft. The OUI field MUST contain a value of (00:50:f2) as specified in [IEEE-OUI].
OUI Type (1 byte): A packet subtype within the universe specific to a particular OUI value. For the Proximity Service Discovery Protocol, the OUI Type MUST contain a value of 6.
Format identifier hash (4 bytes): A value that identifies the format of the data, as specified in section 2.2.2.
Data (variable): Contains user-defined data for discovery.
The transmission order follows the conventions for transmission of MAC protocol data units (MPDUs), as specified in [IEEE802.11-2007] section 7.
The message format of the Beacon frame is as specified in [IEEE802.11-2007] section 7.2.3.1. The message format of the Probe Response frame is as specified in [IEEE802.11-2007] section 7.2.3.9.