Ch20-DHCP and Multicast Flashcards
Any device that uses DHCP protocols to ask to lease an IP address from a DHCP server, or learn and IP settings from that server
DHCP client
The name of the router IOS feature that forwards DHCP messages from clients to servers by changing the destination IP address from 255.255.255.255 to the IP address of the DHCP server
DHCP relay agent
Software that waits for DHCP clients to request to least DHCP addresses as well as listing other important IP settings for the client
DHCP server
IPv4 address 255.255.255.255. A packet sent to this address is sent as a data-link broadcast, but only flows to hosts in the subnet into which it was originally sent. Routers do not forward these packets
Local broadcast address
Specifically, the largest numeric address in a subnet, designed so that packets sent to this address should be delivered to all hosts in that subnet
subnet broadcast address
A special address in each class full network that can be used to broadcast a packet to all hosts in that same glassful network.
network broadcast address
A class D IPv4 address. When used as a destination address in a packet, routers collectively work to deliver copies of the one original packet to all hosts that have previously registered to receive packets sent to that particular address
multicast address
Command reference: Global command that reserves and inclusive range of addresses so that the DHCP server function does no least out the specified addresses
ip DHCP excluded-address first last
Command reference: Creates a pool, by name, and moves the user to DHCP server pool configuration mode
ip dhcp pool pool-name
Command reference: DHCP pool mode subcommand that defines a network or subnet causing the DHCP server to lease out addresses in that subnet
network subnet-id [ddn-mask | prefix}
Command reference: DHCP pool mode subcommand that defines one or more routers as default routers, with that information passed on to clients served by this pool
default-router address1 address2…
Command reference: DHCP pool mode subcommand that defines the list of DNS servers to be used by clients served by this pool.
dns-server address1 address2…
Command reference: DHCP pool mode subcommand that defines the length allowed for a DHCP lease for clients served by this pool.
lease days hours minutes
Command reference: Interface subcommand that tells the router to notice local subnet broadcasts that use UDP, and change the source and destination IP address, enabling DHCP servers to sit on a remote subnet
ip helper-address ip-address
Command reference: Lists the router’s IPv4 address table
show arp show ip arp
Command reference: Lists the currently leased IP addresses on a DHCP server, along with the client identifier and lease time information
show ip dhcp binding