FUJITSU PSWITCH
User’s Guide
98
December/2018
3.1.4.
DHCP (Dynamic Host Configuration Protocol)
3.1.4.1.
DHCP Client
The DHCP client is a UDP protocol that allows devices to obtain stateful DHCP
information such as the IP address, etc. and stateless DHCP information such as
DNS servers, TFTP servers, etc. from the DHCP server. The DHCP client allows the
user to enable on the network port, service port, as well as host and routing
interfaces.
IPv4
DHCPv4 client is implemented based on the RFC 2131 standard, “Dynamic Host
Configuration Protocol”. Refer to RFC 2131 for more protocol details.
DHCPv4 client identifier (Option 61) allows the DHCPv4 server to be configured to
provide an IP address to a switch based on its MAC address or an ID entered into
the system. This value is expected to be unique for all clients in an administrative
domain. This option allows the system to move from one part of the network to
another while maintaining the same IP address. This option is optional and can be
specified while configuring the DHCP on the interfaces.
IPv6
DHCPv6 client interactions are described by RFC 3315. The DHCPv6 client can
configuration of IPv6 global address auto-configuration on the network port,
service port, as well as host and routing interfaces.
3.1.4.2.
DHCP Snooping
DHCP snooping is a security feature that monitors DHCP messages between DHCP
clients and DHCP servers to filter harmful DHCP messages and build a bindings
database. Bindings database entries consist of MAC address
、
IP address
、
VLAN ID
and client port.
DHCP messages can build and maintain DHCP snooping bindings database (Only
for clients on untrusted port). The network administrator also can enter static
binding entry into the DHCP snooping bindings database.
For valid client messages, DHCP snooping compares the source MAC address to the
DHCP client hardware address. When there is a mismatch, DHCP snooping drops
the packet. This is a configurable option.