This field shall specify the time in seconds during which commissioning session establishment is allowed by the Node. This is known as Open Basic Commissioning Window (OBCW). This timeout shall follow guidance as specified in the initial Announcement Duration.
When a Node receives the Open Basic Commissioning Window command, it shall begin advertising on DNS-SD as described in Section 4.3.1, “Commissionable Node Discovery” and for a time period as described in Section 11.19.8.2.1, “CommissioningTimeout Field”. When the command is received by a ICD, it shall enter into active mode. The ICD shall remain in Active Mode as long as one of these conditions is met:
• A commissioning window is open.
• There is an armed fail-safe timer.
Input to the AdministratorCommissioning openBasicCommissioningWindow command
See
MatterSpecification.v13.Core § 11.19.8.2