Siemens SCALANCE W1780 Configuration Manual page 48

IP addresses
5.1 IPv4 / IPv6
Identification of DHCP clients/
server
DHCP
Resolution of IP addresses in
hardware addresses
48
IPv4
Client ID:
● MAC address
● DHCP client ID
● System name
● PROFINET station
name
● IAID and DUID
via UDP with broadcast
ARP (Address Resolution
Protocol)
SCALANCE W1780/W1740 according to IEEE 802.11ac Web Based Management
IPv6
DUID + IAID(s) = exactly one interface of the host
DUID = DHCP unique identifier
Unique identifier of server and clients
IAID = Identity Association Identifier
At least one per interface is generated by the client and re‐
mains unchanged when the DHCP client restarts
Three methods of obtaining the DUID
● DUID-LLT
● DUID-EN
● DUID-LL
via UDP with unicast
RFC 3315, RFC 3363
Stateful DHCPv6
Stateful configuration in which the IPv6 address and the con‐
figuration settings are transferred.
Four DHVPv6 messages are exchanged between client and
server:
1. SOLICIT:
Sent by the DHCPv6 client to localize DHCPv6 servers.
2. ADVERTISE
The available DHCPv6 servers reply to this.
3. REQUEST
The DHCPv6 client requests an IPv6 address and the
configuration settings from the DHCPv6 server.
4. REPLY
The DHCPv6 server sends the IPv6 address and the
configuration settings.
If the client and server support the function "Rapid commit" the
procedure is shortened to two DHCPv6 messages SOLICIT
and REPLY .
Stateless DHCPv6
In stateless DHCPv6, only the configuration settings are trans‐
ferred.
Prefix delegation
The DHCPv6 server delegates the distribution of IPv6 prefixes
to the DHCPv6 client. The DHCPv6 client is also known as PD
router.
NDP (Neighbor Discovery Protocol)
Configuration Manual, 11/2019, C79000-G8976-C485-03