Single Subnet with Link-Local Addresses
A version of this page is also available for
4/8/2010
This implementation supports the installation of the IPv6 protocol on at least two nodes on the same network segment without intermediate routers. A network segment is also known as a link or subnet. The following illustration shows the implementation of two nodes on a single subnet using link-local addresses.
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By default, the IPv6 protocol for Windows Mobile configures link-local addresses for each interface that correspond to installed network interface adapters.
Link-local addresses have the prefix of FE80::/64. The link-local address of a node is the combination of the prefix FE80::/64 and the 64-bit interface identifier expressed in colon-hexadecimal notation. The interface identifier is the last 64 bits of the IPv6 address, and is derived from the 48-bit Ethernet MAC address of the network adapter. This is described in detail and examples are provided in IPv6 Interface Identifiers.
Testing connectivity between two link-local hosts
To test IPv6 connectivity between two link-local hosts, you can perform a simple ping to exchange Internet Control Message Protocol version 6 (ICMPv6) Echo Request and Echo Reply messages.
To perform the ping, completing the following steps:
- Use ipconfig /all or ipv6 if on Host A to obtain the link-local address and the interface ID for the Ethernet interface.
For example, the link-local address of Host A is FE80::210:5AFF:FEAA:20A2 and the interface ID of the Ethernet interface is 4. - Use ipconfig /all or ipv6 if on Host B to obtain the link-local address and the interface ID for the Ethernet interface.
For example, the link-local address of Host B is FE80::260:97FF:FE02:6EA5 and the interface ID for the Ethernet interface is 3. - From Host A, use Ping.exe to ping Host B.
For example, ping FE80::260:97FF:FE02:6EA5%4
When you specify a link-local destination address, specify the scope ID to make the scope (area of the network) of the traffic specific.
For example, on a computer with multiple Ethernet adapters that are connected to separate links, each Ethernet adapter is assigned a link-local address. Destination link-local addresses in this implementation are ambiguous because a specific link-local address can be assigned to multiple nodes located on the links that are reachable from all of the installed Ethernet adapters. To define the area of the network for which the destination is intended, the scope ID is used to indicate the network interface over which traffic is sent and received. In the IPv6 protocol, the scope ID is the interface identifier. You can display the interface identifier by using ipconfig /all or ipv6 if. The interface identifier is defined locally on each IPv6 host. Because of this, the interface identifier used by Host A to reach Host B might not be the same as the interface identifier used by Host B to reach Host A.
The notation that is used to specify the scope ID with an address is Address**%**ScopeID.