NDIS defines object identifier (OID) values to identify adapter parameters, which include operating parameters such as device characteristics, configurable settings and statistics. For more information about OIDs, see NDIS OIDs.
Filter drivers can query or set the operating parameters of underlying drivers or filter the OID requests of overlying drivers.
NDIS also provides a direct OID request interface for NDIS 6.1 and later filter drivers. The direct OID request path supports OID requests that are queried or set frequently. For example, the IPsec offload version 2 (IPsecv2) interface provides the OID_TCP_TASK_IPSEC_OFFLOAD_V2_ADD_SA OID for direct OID requests. The direct OID request interface is optional for NDIS drivers.
The following topics provide more information about filter driver OID requests: