IP Helper

Overview of the IP Helper technology.

To develop IP Helper, you need these headers:

For programming guidance for this technology, see:

Enumerations

 
DNS_SERVER_PROPERTY_TYPE

Defines constants that specify the validity of the property held in the DNS_SERVER_PROPERTY::Property member.
IF_OPER_STATUS

The IF_OPER_STATUS enumeration specifies the operational status of an interface.
NET_ADDRESS_FORMAT

The NET_ADDRESS_FORMAT enumeration specifies the format of a network address returned by the ParseNetworkString function.
NL_DAD_STATE

The IP_DAD_STATE enumeration specifies information about the duplicate address detection (DAD) state for an IPv4 or IPv6 address.
NL_NETWORK_CONNECTIVITY_COST_HINT

Defines constants that specify hints about the usage charge for a network connection.
NL_NETWORK_CONNECTIVITY_LEVEL_HINT

Defines constants that specify hints about a level of network connectivity.
NL_PREFIX_ORIGIN

The IP_PREFIX_ORIGIN enumeration specifies the origin of an IPv4 or IPv6 address prefix, and is used with the IP_ADAPTER_UNICAST_ADDRESS structure.
NL_SUFFIX_ORIGIN

The IP_SUFFIX_ORIGIN enumeration specifies the origin of an IPv4 or IPv6 address suffix, and is used with the IP_ADAPTER_UNICAST_ADDRESS structure.
SCOPE_LEVEL

The SCOPE_LEVEL enumeration is used with the IP_ADAPTER_ADDRESSES structure to identify scope levels for IPv6 addresses.
TCP_BOOLEAN_OPTIONAL

Defines the states that a caller can specify when updating a member in the read/write information for a TCP connection.
TCP_ESTATS_TYPE

Defines the type of extended statistics for a TCP connection that is requested or being set.
TCP_SOFT_ERROR

Defines the reason for non-fatal or soft errors recorded on a TCP connection.
TCP_TABLE_CLASS

Defines the set of values used to indicate the type of table returned by calls to GetExtendedTcpTable.
TCPIP_OWNER_MODULE_INFO_CLASS

Defines the type of module information structure passed to calls of the GetOwnerModuleFromXXXEntry family.
UDP_TABLE_CLASS

Defines the set of values used to indicate the type of table returned by calls to GetExtendedUdpTable.

Functions

 
AddIPAddress

The AddIPAddress function adds the specified IPv4 address to the specified adapter.
AllocateAndGetTcpExTableFromStack

Retrieves the TCP connection table and allocates memory from the local heap to store the table.
AllocateAndGetUdpExTableFromStack

Retrieves the UDP connection table and allocates memory from the local heap to store the table.
CancelIfTimestampConfigChange

This function is reserved for system use, and you should not call it from your code. (CancelIfTimestampConfigChange)
CancelIPChangeNotify

Cancels notification of IPv4 address and route changes previously requested with successful calls to the NotifyAddrChange or NotifyRouteChange functions.
CancelMibChangeNotify2

Deregisters for change notifications for IP interface changes, IP address changes, IP route changes, Teredo port changes, and when the unicast IP address table is stable and can be retrieved.
CaptureInterfaceHardwareCrossTimestamp

Retrieves cross timestamp info for a network adapter.
ConvertInterfaceAliasToLuid

Converts an interface alias name for a network interface to the locally unique identifier (LUID) for the interface.
ConvertInterfaceGuidToLuid

Converts a globally unique identifier (GUID) for a network interface to the locally unique identifier (LUID) for the interface.
ConvertInterfaceIndexToLuid

Converts a local index for a network interface to the locally unique identifier (LUID) for the interface.
ConvertInterfaceLuidToAlias

Converts a locally unique identifier (LUID) for a network interface to an interface alias.
ConvertInterfaceLuidToGuid

Converts a locally unique identifier (LUID) for a network interface to a globally unique identifier (GUID) for the interface.
ConvertInterfaceLuidToIndex

Converts a locally unique identifier (LUID) for a network interface to the local index for the interface.
ConvertInterfaceLuidToNameA

Converts a locally unique identifier (LUID) for a network interface to the ANSI interface name.
ConvertInterfaceLuidToNameW

Converts a locally unique identifier (LUID) for a network interface to the Unicode interface name.
ConvertInterfaceNameToLuidA

Converts an ANSI network interface name to the locally unique identifier (LUID) for the interface.
ConvertInterfaceNameToLuidW

Converts a Unicode network interface name to the locally unique identifier (LUID) for the interface.
ConvertIpv4MaskToLength

Converts an IPv4 subnet mask to an IPv4 prefix length.
ConvertLengthToIpv4Mask

Converts an IPv4 prefix length to an IPv4 subnet mask.
CreateAnycastIpAddressEntry

Adds a new anycast IP address entry on the local computer.
CreateIpForwardEntry

The CreateIpForwardEntry function creates a route in the local computer's IPv4 routing table.
CreateIpForwardEntry2

Creates a new IP route entry on the local computer.
CreateIpNetEntry

The CreateIpNetEntry function creates an Address Resolution Protocol (ARP) entry in the ARP table on the local computer.
CreateIpNetEntry2

Creates a new neighbor IP address entry on the local computer.
CreatePersistentTcpPortReservation

Creates a persistent TCP port reservation for a consecutive block of TCP ports on the local computer.
CreatePersistentUdpPortReservation

Creates a persistent UDP port reservation for a consecutive block of UDP ports on the local computer.
CreateProxyArpEntry

The CreateProxyArpEnry function creates a Proxy Address Resolution Protocol (PARP) entry on the local computer for the specified IPv4 address.
CreateSortedAddressPairs

Takes a supplied list of potential IP destination addresses, pairs the destination addresses with the host machine's local IP addresses, and sorts the pairs according to which address pair is best suited for communication between the two peers.
CreateUnicastIpAddressEntry

Adds a new unicast IP address entry on the local computer.
DeleteAnycastIpAddressEntry

Deletes an existing anycast IP address entry on the local computer.
DeleteIPAddress

The DeleteIPAddress function deletes an IP address previously added using AddIPAddress.
DeleteIpForwardEntry

Deletes an existing route in the local computer's IPv4 routing table.
DeleteIpForwardEntry2

Deletes an IP route entry on the local computer.
DeleteIpNetEntry

The DeleteIpNetEntry function deletes an ARP entry from the ARP table on the local computer.
DeleteIpNetEntry2

Deletes a neighbor IP address entry on the local computer.
DeletePersistentTcpPortReservation

Deletes a persistent TCP port reservation for a consecutive block of TCP ports on the local computer. (DeletePersistentTcpPortReservation)
DeletePersistentUdpPortReservation

Deletes a persistent TCP port reservation for a consecutive block of TCP ports on the local computer. (DeletePersistentUdpPortReservation)
DeleteProxyArpEntry

The DeleteProxyArpEntry function deletes the PARP entry on the local computer specified by the dwAddress and dwIfIndex parameters.
DeleteUnicastIpAddressEntry

Deletes an existing unicast IP address entry on the local computer.
DisableMediaSense

The DisableMediaSense function disables the media sensing capability of the TCP/IP stack on a local computer.
EnableRouter

The EnableRouter function turns on IPv4 forwarding on the local computer. EnableRouter also increments a reference count that tracks the number of requests to enable IPv4 forwarding.
FlushIpNetTable

The FlushIpNetTable function deletes all ARP entries for the specified interface from the ARP table on the local computer.
FlushIpNetTable2

The FlushIpNetTable2 function flushes the IP neighbor table on the local computer.
FlushIpPathTable

The FlushIpPathTable function flushes the IP path table on the local computer.
FreeInterfaceDnsSettings

Frees the settings object returned by GetInterfaceDnsSettings.
FreeMibTable

Frees the buffer allocated by the functions that return tables of network interfaces, addresses, and routes (GetIfTable2 and GetAnycastIpAddressTable, for example).
GetAdapterIndex

The GetAdapterIndex function obtains the index of an adapter, given its name.
GetAdapterOrderMap

The GetAdapterOrderMap function obtains an adapter order map that indicates priority for interfaces on the local computer.
GetAdaptersAddresses

Retrieves the addresses associated with the adapters on the local computer.
GetAdaptersInfo

The GetAdaptersInfo function retrieves adapter information for the local computer.
GetAnycastIpAddressEntry

Retrieves information for an existing anycast IP address entry on the local computer.
GetAnycastIpAddressTable

Retrieves the anycast IP address table on the local computer.
GetBestInterface

The GetBestInterface function retrieves the index of the interface that has the best route to the specified IPv4 address.
GetBestInterfaceEx

The GetBestInterfaceEx function retrieves the index of the interface that has the best route to the specified IPv4 or IPv6 address.
GetBestRoute

The GetBestRoute function retrieves the best route to the specified destination IP address.
GetBestRoute2

Retrieves the IP route entry on the local computer for the best route to the specified destination IP address.
GetDefaultCompartmentId

The GetDefaultCompartmentId function retrieves the default network routing compartment identifier for the local computer.
GetExtendedTcpTable

Retrieves a table that contains a list of TCP endpoints available to the application.
GetExtendedUdpTable

Retrieves a table that contains a list of UDP endpoints available to the application.
GetFriendlyIfIndex

Takes an interface index and returns a backward-compatible interface index, that is, an index that uses only the lower 24 bits.
GetIcmpStatistics

The GetIcmpStatistics function retrieves the Internet Control Message Protocol (ICMP) for IPv4 statistics for the local computer.
GetIcmpStatisticsEx

The GetIcmpStatisticsEx function retrieves Internet Control Message Protocol (ICMP) statistics for the local computer. The GetIcmpStatisticsEx function is capable of retrieving IPv6 ICMP statistics.
GetIfEntry

The GetIfEntry function retrieves information for the specified interface on the local computer.
GetIfEntry2

Retrieves information for the specified interface on the local computer.
GetIfEntry2Ex

Retrieves the specified level of information for the specified interface on the local computer.
GetIfStackTable

Retrieves a table of network interface stack row entries that specify the relationship of the network interfaces on an interface stack.
GetIfTable

The GetIfTable function retrieves the MIB-II interface table.
GetIfTable2

Retrieves the MIB-II interface table. (GetIfTable2)
GetIfTable2Ex

Retrieves the MIB-II interface table. (GetIfTable2Ex)
GetInterfaceActiveTimestampCapabilities

Retrieves the currently enabled timestamp capabilities of a network adapter.
GetInterfaceCurrentTimestampCapabilities

This function is reserved for system use, and you should not call it from your code. (GetInterfaceCurrentTimestampCapabilities)
GetInterfaceDnsSettings

Retrieves the DNS settings from the interface specified in the Interface parameter.
GetInterfaceHardwareTimestampCapabilities

This function is reserved for system use, and you should not call it from your code. (GetInterfaceHardwareTimestampCapabilities)
GetInterfaceInfo

The GetInterfaceInfo function obtains the list of the network interface adapters with IPv4 enabled on the local system.
GetInterfaceSupportedTimestampCapabilities

Retrieves the supported timestamp capabilities of a network adapter.
GetInvertedIfStackTable

Retrieves a table of inverted network interface stack row entries that specify the relationship of the network interfaces on an interface stack.
GetIpAddrTable

The GetIpAddrTable function retrieves the interface�to�IPv4 address mapping table.
GetIpErrorString

The GetIpErrorString function retrieves an IP Helper error string.
GetIpForwardEntry2

Retrieves information for an IP route entry on the local computer.
GetIpForwardTable

The GetIpForwardTable function retrieves the IPv4 routing table.
GetIpForwardTable2

The GetIpForwardTable2 function retrieves the IP route entries on the local computer.
GetIpInterfaceEntry

Retrieves IP information for the specified interface on the local computer.
GetIpInterfaceTable

Retrieves the IP interface entries on the local computer.
GetIpNetEntry2

Retrieves information for a neighbor IP address entry on the local computer.
GetIpNetTable

The GetIpNetTable function retrieves the IPv4 to physical address mapping table.
GetIpNetTable2

The GetIpNetTable2 function retrieves the IP neighbor table on the local computer.
GetIpNetworkConnectionBandwidthEstimates

Retrieves historical bandwidth estimates for a network connection on the specified interface.
GetIpPathEntry

Retrieves information for a IP path entry on the local computer.
GetIpPathTable

The GetIpPathTable function retrieves the IP path table on the local computer.
GetIpStatistics

The GetIpStatistics function retrieves the IP statistics for the current computer.
GetIpStatisticsEx

The GetIpStatisticsEx function retrieves the Internet Protocol (IP) statistics for the current computer.
GetMulticastIpAddressEntry

Retrieves information for an existing multicast IP address entry on the local computer.
GetMulticastIpAddressTable

Retrieves the multicast IP address table on the local computer.
GetNetworkConnectivityHint

Retrieves the aggregate level and cost of network connectivity that an application or service is likely to experience.
GetNetworkConnectivityHintForInterface

Retrieves the level and cost of network connectivity for the specified interface.
GetNetworkParams

The GetNetworkParams function retrieves network parameters for the local computer.
GetNumberOfInterfaces

The GetNumberOfInterfaces functions retrieves the number of interfaces on the local computer.
GetOwnerModuleFromTcp6Entry

Retrieves data about the module that issued the context bind for a specific IPv6 TCP endpoint in a MIB table row.
GetOwnerModuleFromTcpEntry

Retrieves data about the module that issued the context bind for a specific IPv4 TCP endpoint in a MIB table row.
GetOwnerModuleFromUdp6Entry

Retrieves data about the module that issued the context bind for a specific IPv6 UDP endpoint in a MIB table row.
GetOwnerModuleFromUdpEntry

Retrieves data about the module that issued the context bind for a specific IPv4 UDP endpoint in a MIB table row.
GetPerAdapterInfo

The GetPerAdapterInfo function retrieves information about the adapter corresponding to the specified interface.
GetPerTcp6ConnectionEStats

Retrieves extended statistics for an IPv6 TCP connection.
GetPerTcpConnectionEStats

Retrieves extended statistics for an IPv4 TCP connection.
GetRTTAndHopCount

The GetRTTAndHopCount function determines the round-trip time (RTT) and hop count to the specified destination.
GetTcp6Table

Retrieves the TCP connection table for IPv6. (GetTcp6Table)
GetTcp6Table2

Retrieves the TCP connection table for IPv6. (GetTcp6Table2)
GetTcpStatistics

The GetTcpStatistics function retrieves the TCP statistics for the local computer.
GetTcpStatisticsEx

The GetTcpStatisticsEx function retrieves the Transmission Control Protocol (TCP) statistics for the current computer.
GetTcpStatisticsEx2

The GetTcpStatisticsEx2 function retrieves the Transmission Control Protocol (TCP) statistics for the current computer.
GetTcpTable

Retrieves the IPv4 TCP connection table. (GetTcpTable)
GetTcpTable2

Retrieves the IPv4 TCP connection table. (GetTcpTable2)
GetTeredoPort

Retrieves the dynamic UDP port number used by the Teredo client on the local computer.
GetUdp6Table

Retrieves the IPv6 User Datagram Protocol (UDP) listener table.
GetUdpStatistics

The GetUdpStatistics function retrieves the User Datagram Protocol (UDP) statistics for the local computer.
GetUdpStatisticsEx

The GetUdpStatisticsEx function retrieves the User Datagram Protocol (UDP) statistics for the current computer.
GetUdpStatisticsEx2

The GetUdpStatisticsEx2 function retrieves the User Datagram Protocol (UDP) statistics for the current computer.
GetUdpTable

Retrieves the IPv4 User Datagram Protocol (UDP) listener table.
GetUnicastIpAddressEntry

Retrieves information for an existing unicast IP address entry on the local computer.
GetUnicastIpAddressTable

Retrieves the unicast IP address table on the local computer.
GetUniDirectionalAdapterInfo

The GetUniDirectionalAdapterInfo function retrieves information about the unidirectional adapters installed on the local computer. A unidirectional adapter is an adapter that can receive datagrams, but not transmit them.
Icmp6CreateFile

The Icmp6CreateFile function opens a handle on which IPv6 ICMP echo requests can be issued.
Icmp6ParseReplies

The Icmp6ParseReplies function parses the reply buffer provided and returns an IPv6 ICMPv6 echo response reply if found.
Icmp6SendEcho2

The Icmp6SendEcho2 function sends an IPv6 ICMPv6 echo request and returns either immediately (if Event or ApcRoutine is non-NULL) or returns after the specified time-out. The ReplyBuffer contains the IPv6 ICMPv6 echo response, if any.
IcmpCloseHandle

The IcmpCloseHandle function closes a handle opened by a call to the IcmpCreateFile or Icmp6CreateFile functions.
IcmpCreateFile

The IcmpCreateFile function opens a handle on which IPv4 ICMP echo requests can be issued.
IcmpParseReplies

Parses the reply buffer provided and returns the number of ICMP echo request responses found.
IcmpSendEcho

The IcmpSendEcho function sends an IPv4 ICMP echo request and returns any echo response replies. The call returns when the time-out has expired or the reply buffer is filled.
IcmpSendEcho2

The IcmpSendEcho2 function sends an IPv4 ICMP echo request, and returns either immediately (if Event or ApcRoutine is non-NULL), or returns after the specified time-out. The ReplyBuffer contains the ICMP echo responses, if any.
IcmpSendEcho2Ex

Sends an IPv4 ICMP echo request and returns either immediately (if Event or ApcRoutine is non-NULL) or returns after the specified time-out. The ReplyBuffer contains the ICMP responses, if any.
if_indextoname

Converts the local index for a network interface to the ANSI interface name.
if_nametoindex

Converts the ANSI interface name for a network interface to the local index for the interface.
InitializeIpForwardEntry

Initializes a MIB_IPFORWARD_ROW2 structure with default values for an IP route entry on the local computer.
InitializeIpInterfaceEntry

Initializes the members of an MIB_IPINTERFACE_ROW entry with default values.
InitializeUnicastIpAddressEntry

Initializes a MIB_UNICASTIPADDRESS_ROW structure with default values for a unicast IP address entry on the local computer.
INTERFACE_TIMESTAMP_CONFIG_CHANGE_CALLBACK

A callback function that you implement in your app in order to be notified of changes to the timestamp capabilities of a network adapter.
IpReleaseAddress

The IpReleaseAddress function releases an IPv4 address previously obtained through the Dynamic Host Configuration Protocol (DHCP).
IpRenewAddress

The IpRenewAddressfunction renews a lease on an IPv4 address previously obtained through Dynamic Host Configuration Protocol (DHCP).
LookupPersistentTcpPortReservation

Looks up the token for a persistent TCP port reservation for a consecutive block of TCP ports on the local computer.
LookupPersistentUdpPortReservation

Looks up the token for a persistent UDP port reservation for a consecutive block of TCP ports on the local computer.
NhpAllocateAndGetInterfaceInfoFromStack

The NhpAllocateAndGetInterfaceInfoFromStack function obtains adapter information about the local computer.
NotifyAddrChange

The NotifyAddrChange function causes a notification to be sent to the caller whenever a change occurs in the table that maps IPv4 addresses to interfaces.
NotifyIfTimestampConfigChange

This function is reserved for system use, and you should not call it from your code. (NotifyIfTimestampConfigChange)
NotifyIpInterfaceChange

Registers to be notified for changes to all IP interfaces, IPv4 interfaces, or IPv6 interfaces on a local computer.
NotifyNetworkConnectivityHintChange

Registers an application-defined callback function, to be called when the aggregate network connectivity level and cost hints change.
NotifyRouteChange

The NotifyRouteChange function causes a notification to be sent to the caller whenever a change occurs in the IPv4 routing table.
NotifyRouteChange2

Registers to be notified for changes to IP route entries on a local computer.
NotifyStableUnicastIpAddressTable

Retrieves the stable unicast IP address table on a local computer.
NotifyTeredoPortChange

Registers to be notified for changes to the UDP port number used by the Teredo client for the Teredo service port on a local computer.
NotifyUnicastIpAddressChange

Registers to be notified for changes to all unicast IP interfaces, unicast IPv4 addresses, or unicast IPv6 addresses on a local computer.
ParseNetworkString

Parses the input network string and checks whether it is a legal representation of the specified IP network string type. If the string matches a type and its specification, the function can optionally return the parsed result.
PNETWORK_CONNECTIVITY_HINT_CHANGE_CALLBACK

An application-defined function called whenever there's a change in the network aggregate connectivity level and cost hints.
RegisterInterfaceTimestampConfigChange

Registers a user-implemented callback function, which the system calls to notify you of a timestamp capability change.
ResolveIpNetEntry2

Resolves the physical address for a neighbor IP address entry on the local computer. (ResolveIpNetEntry2)
ResolveNeighbor

Resolves the physical address for a neighbor IP address entry on the local computer. (ResolveNeighbor)
RestoreMediaSense

The RestoreMediaSense function restores the media sensing capability of the TCP/IP stack on a local computer on which the DisableMediaSense function was previously called.
RtlEthernetAddressToStringA

Converts a binary Ethernet address to a string representation of the Ethernet MAC address. (ANSI)
RtlEthernetAddressToStringW

Converts a binary Ethernet address to a string representation of the Ethernet MAC address. (Unicode)
RtlEthernetStringToAddressA

Converts a string representation of an Ethernet MAC address to a binary format of the Ethernet address. (ANSI)
RtlEthernetStringToAddressW

Converts a string representation of an Ethernet MAC address to a binary format of the Ethernet address. (Unicode)
RtlIpv4AddressToStringA

Converts an IPv4 address to a string in Internet standard dotted-decimal format. (ANSI)
RtlIpv4AddressToStringExA

Converts an IPv4 address and port number to a string in Internet standard format. (ANSI)
RtlIpv4AddressToStringExW

Converts an IPv4 address and port number to a string in Internet standard format. (Unicode)
RtlIpv4AddressToStringW

Converts an IPv4 address to a string in Internet standard dotted-decimal format. (Unicode)
RtlIpv4StringToAddressA

Converts a string representation of an IPv4 address to a binary IPv4 address. (ANSI)
RtlIpv4StringToAddressExA

Converts a string representation of an IPv4 address and port number to a binary IPv4 address and port. (ANSI)
RtlIpv4StringToAddressExW

Converts a string representation of an IPv4 address and port number to a binary IPv4 address and port. (Unicode)
RtlIpv4StringToAddressW

Converts a string representation of an IPv4 address to a binary IPv4 address. (Unicode)
RtlIpv6AddressToStringA

Converts an IPv6 address to a string in Internet standard format. (ANSI)
RtlIpv6AddressToStringExA

Converts an IPv6 address, scope ID, and port number to a string. (ANSI)
RtlIpv6AddressToStringExW

Converts an IPv6 address, scope ID, and port number to a string. (Unicode)
RtlIpv6AddressToStringW

Converts an IPv6 address to a string in Internet standard format. (Unicode)
RtlIpv6StringToAddressA

Converts a string representation of an IPv6 address to a binary IPv6 address. (ANSI)
RtlIpv6StringToAddressExA

Converts a string representation of an IPv6 address, scope ID, and port number to a binary IPv6 address, scope ID, and port. (ANSI)
RtlIpv6StringToAddressExW

Converts a string representation of an IPv6 address, scope ID, and port number to a binary IPv6 address, scope ID, and port. (Unicode)
RtlIpv6StringToAddressW

Converts a string representation of an IPv6 address to a binary IPv6 address. (Unicode)
SendARP

The SendARP function sends an Address Resolution Protocol (ARP) request to obtain the physical address that corresponds to the specified destination IPv4 address.
SetIfEntry

The SetIfEntry function sets the administrative status of an interface.
SetInterfaceDnsSettings

Sets the per-interface DNS settings specified in the Settings parameter.
SetIpForwardEntry

The SetIpForwardEntry function modifies an existing route in the local computer's IPv4 routing table.
SetIpForwardEntry2

Sets the properties of an IP route entry on the local computer.
SetIpInterfaceEntry

Sets the properties of an IP interface on the local computer.
SetIpNetEntry

The SetIpNetEntry function modifies an existing ARP entry in the ARP table on the local computer.
SetIpNetEntry2

Sets the physical address of an existing neighbor IP address entry on the local computer.
SetIpStatistics

The SetIpStatistics function toggles IP forwarding on or off and sets the default time-to-live (TTL) value for the local computer.
SetIpStatisticsEx

Toggles IP forwarding on or off and sets the default time-to-live (TTL) value for the local computer.
SetIpTTL

The SetIpTTL function sets the default time-to-live (TTL) value for the local computer.
SetPerTcp6ConnectionEStats

Sets a value in the read/write information for an IPv6 TCP connection. This function is used to enable or disable extended statistics for an IPv6 TCP connection.
SetPerTcpConnectionEStats

Sets a value in the read/write information for an IPv4 TCP connection. This function is used to enable or disable extended statistics for an IPv4 TCP connection.
SetTcpEntry

The SetTcpEntry function sets the state of a TCP connection.
SetUnicastIpAddressEntry

Sets the properties of an existing unicast IP address entry on the local computer.
UnenableRouter

The UnenableRouter function decrements the reference count that tracks the number of requests to enable IPv4 forwarding. When this reference count reaches zero, UnenableRouter turns off IPv4 forwarding on the local computer.
UnregisterInterfaceTimestampConfigChange

Cancels notifications about timestamp capability changes by unregistering the callback function you registered in a call to RegisterInterfaceTimestampConfigChange.

Structures

 
ARP_SEND_REPLY

The ARP_SEND_REPLY structure stores information about an Address Resolution Protocol (ARP) reply messages.
DNS_DOH_SERVER_SETTINGS

Describes a DNS-over-HTTPS server.
DNS_INTERFACE_SETTINGS

Represents the DNS settings that can be configured on a given interface by calling the SetInterfaceDnsSettings function or retrieved for a given interface by calling the GetInterfaceDnsSettings function. (DNS_INTERFACE_SETTINGS)
DNS_INTERFACE_SETTINGS_EX

Represents the DNS settings that can be configured on a given interface by calling the SetInterfaceDnsSettings function or retrieved for a given interface by calling the GetInterfaceDnsSettings function. (DNS_INTERFACE_SETTINGS_EX)
DNS_INTERFACE_SETTINGS3

Represents the DNS settings that can be configured on a given interface by calling the SetInterfaceDnsSettings function or retrieved for a given interface by calling the GetInterfaceDnsSettings function. (DNS_INTERFACE_SETTINGS3)
DNS_SERVER_PROPERTY

Describes a DNS server property, which is set in the DNS_INTERFACE_SETTINGS3 structure, and configured through the SetInterfaceDnsSettings function.
DNS_SERVER_PROPERTY_TYPES

Contains a pointer to a DNS server property. The type of the property depends on the value of DNS_SERVER_PROPERTY::Type.
FIXED_INFO_W2KSP1

The FIXED_INFO structure contains information that is the same across all the interfaces on a computer.
ICMP_ECHO_REPLY

Describes the data returned in response to an IPv4 echo request.
ICMP_ECHO_REPLY32

Describes the data returned in response to an IPv4 echo request on a 64-bit platform.
ICMPV6_ECHO_REPLY_LH

Describes the data returned in response to an IPv6 echo request.
IN_ADDR

The in_addr structure represents an IPv4 address.
INTERFACE_HARDWARE_CROSSTIMESTAMP

Describes a cross timestamp retrieved from a network adapter.
INTERFACE_HARDWARE_TIMESTAMP_CAPABILITIES

Describes the timestamping capabilities of a network interface card's (NIC's) hardware.
INTERFACE_SOFTWARE_TIMESTAMP_CAPABILITIES

Describes the software timestamping capabilities of a NIC's miniport driver.
INTERFACE_TIMESTAMP_CAPABILITIES

Describes the exact timestamp capabilities that a network adapter supports.
INTERFACE_TIMESTAMP_CAPABILITY_FLAGS

This structure is reserved for system use, and you should not use it in your code.
IP_ADAPTER_ADDRESSES_LH

The IP_ADAPTER_ADDRESSES_LH structure (iptypes.h) is the header node for a linked list of addresses for a particular adapter.
IP_ADAPTER_ADDRESSES_XP

The IP_ADAPTER_ADDRESSES_XP structure (iptypes.h) is the header node for a linked list of addresses for a particular adapter.
IP_ADAPTER_ANYCAST_ADDRESS_XP

Stores a single anycast IP address in a linked list of addresses for a particular adapter.
IP_ADAPTER_DNS_SERVER_ADDRESS_XP

The IP_ADAPTER_DNS_SERVER_ADDRESS structure stores a single DNS server address in a linked list of DNS server addresses for a particular adapter.
IP_ADAPTER_DNS_SUFFIX

The IP_ADAPTER_DNS_SUFFIX structure stores a DNS suffix in a linked list of DNS suffixes for a particular adapter.
IP_ADAPTER_GATEWAY_ADDRESS_LH

Stores a single gateway address in a linked list of gateway addresses for a particular adapter.
IP_ADAPTER_INDEX_MAP

The IP_ADAPTER_INDEX_MAP structure stores the interface index associated with a network adapter with IPv4 enabled together with the name of the network adapter.
IP_ADAPTER_INFO

Contains information about a particular network adapter on the local computer.
IP_ADAPTER_MULTICAST_ADDRESS_XP

The IP_ADAPTER_MULTICAST_ADDRESS structure stores a single multicast address in a linked-list of addresses for a particular adapter.
IP_ADAPTER_ORDER_MAP

The IP_ADAPTER_ORDER_MAP structure stores an array of information about adapters and their relative priority on the local computer.
IP_ADAPTER_PREFIX_XP

Stores an IP address prefix.I
IP_ADAPTER_UNICAST_ADDRESS_LH

The IP_ADAPTER_UNICAST_ADDRESS_LH structure (iptypes.h) stores a single unicast IP address in a linked list of IP addresses for a particular adapter.
IP_ADAPTER_UNICAST_ADDRESS_XP

The IP_ADAPTER_UNICAST_ADDRESS_XP structure (iptypes.h) stores a single unicast IP address in a linked list of IP addresses for a particular adapter.
IP_ADAPTER_WINS_SERVER_ADDRESS_LH

Stores a single Windows Internet Name Service (WINS) server address in a linked list of WINS server addresses for a particular adapter.
IP_ADDR_STRING

Represents a node in a linked-list of IPv4 addresses.
IP_ADDRESS_PREFIX

Stores an IP address prefix. (IP_ADDRESS_PREFIX)
IP_ADDRESS_STRING

Stores an IPv4 address in dotted decimal notation.
IP_INTERFACE_INFO

The IP_INTERFACE_INFO structure contains a list of the network interface adapters with IPv4 enabled on the local system.
IP_INTERFACE_NAME_INFO_W2KSP1

Contains information about an IPv4 interface on the local computer.
IP_MCAST_COUNTER_INFO

The IP_MCAST_COUNTER_INFO structure stores statistical information about Multicast traffic.
IP_OPTION_INFORMATION

Describes the options to be included in the header of an IP packet.
IP_OPTION_INFORMATION32

Describes the options to be included in the header of an IP packet on a 64-bit platform.
IP_PER_ADAPTER_INFO_W2KSP1

The IP_PER_ADAPTER_INFO structure contains information specific to a particular adapter.
IP_UNIDIRECTIONAL_ADAPTER_ADDRESS

The IP_UNIDIRECTIONAL_ADAPTER_ADDRESS structure stores the IPv4 addresses associated with a unidirectional adapter.
IPV6_ADDRESS_EX

Stores an IPv6 address.
NET_ADDRESS_INFO

Contains IP address information returned by the ParseNetworkString function.
NET_LUID_LH

The locally unique identifier (LUID) for a network interface.
NL_BANDWIDTH_INFORMATION

Contains read-only information on the available bandwidth estimates and associated variance as determined by the TCP/IP stack.
NL_NETWORK_CONNECTIVITY_HINT

Describes a level of network connectivity, the usage charge for a network connection, and other members reflecting cost factors.
SOCKADDR_IN6_PAIR

Contains pointers to a pair of IP addresses that represent a source and destination address pair.
SOCKADDR_INET

Contains an IPv4, an IPv6 address, or an address family.
TCP_ESTATS_BANDWIDTH_ROD_v0

Contains read-only dynamic information for extended TCP statistics on bandwidth estimation for a TCP connection.
TCP_ESTATS_BANDWIDTH_RW_v0

Contains read/write configuration information for extended TCP statistics on bandwidth estimation for a TCP connection.
TCP_ESTATS_DATA_ROD_v0

Contains read-only dynamic information for extended TCP statistics on data transfer for a TCP connection.
TCP_ESTATS_DATA_RW_v0

Contains read/write configuration information for extended TCP statistics on data transfer for a TCP connection.
TCP_ESTATS_FINE_RTT_ROD_v0

Contains read-only dynamic information for extended TCP statistics on fine-grained round-trip time (RTT) estimation for a TCP connection.
TCP_ESTATS_FINE_RTT_RW_v0

Contains read/write configuration information for extended TCP statistics on fine-grained round-trip time (RTT) estimation statistics for a TCP connection.
TCP_ESTATS_OBS_REC_ROD_v0

Contains read-only dynamic information for extended TCP statistics observed on the remote receiver for a TCP connection.
TCP_ESTATS_OBS_REC_RW_v0

Contains read/write configuration information for extended TCP statistics observed on the remote receiver for a TCP connection.
TCP_ESTATS_PATH_ROD_v0

Contains read-only dynamic information for extended TCP statistics on network path measurement for a TCP connection.
TCP_ESTATS_PATH_RW_v0

Contains read/write configuration information for extended TCP statistics on path measurement for a TCP connection.
TCP_ESTATS_REC_ROD_v0

Contains read-only dynamic information for extended TCP statistics on the local receiver for a TCP connection.
TCP_ESTATS_REC_RW_v0

Contains read/write configuration information for extended TCP statistics on the local receiver for a TCP connection.
TCP_ESTATS_SEND_BUFF_ROD_v0

Contains read-only dynamic information for extended TCP statistics on output queuing for a TCP connection.
TCP_ESTATS_SEND_BUFF_RW_v0

Contains read/write configuration information for extended TCP statistics on output queuing for a TCP connection.
TCP_ESTATS_SND_CONG_ROD_v0

Contains read-only dynamic information for extended TCP statistics on sender congestion related data for a TCP connection.
TCP_ESTATS_SND_CONG_ROS_v0

Contains read-only static information for extended TCP statistics on the maximum congestion window for a TCP connection.
TCP_ESTATS_SND_CONG_RW_v0

Contains read/write configuration information for extended TCP statistics on sender congestion for a TCP connection.
TCP_ESTATS_SYN_OPTS_ROS_v0

Contains read-only static information for extended TCP statistics on SYN exchange for a TCP connection.
TCP_RESERVE_PORT_RANGE

The TCP_RESERVE_PORT_RANGE structure specifies a TCP port range to reserve.
TCPIP_OWNER_MODULE_BASIC_INFO

Contains pointers to the module name and module path values associated with a TCP connection. The TCPIP_OWNER_MODULE_BASIC_INFO structure is returned by the GetOwnerModuleFromTcpEntry and GetOwnerModuleFromTcp6Entry functions.