ELSA manual Dhcp client, Dhcp server, Cable modem really belongs to two LANs

Operating modes and functions 41

The cable modem really belongs to two LANs:

KOn one side it is a part of the LAN of the cable network operator and forms a LAN together with the headend and all connected cable modems. The cable network operator assigns the IP addresses to the participants via DHCP.

KOn the other side the cable modem forms a separate LAN with one or more connected computers. DHCP can also be used to manage addresses within your own LAN.

The cable modem thus functions as a DHCP client and as a DHCP server.

Whenever IP addresses of the cable modem are mentioned in the following paragraphs, this is a reference to the LAN IP address of the ELSA MicroLink Cable, unless something else is explicitly stated.

The DHCP client

The cable IP address for the exchange of data in the cable network is assigned via DHCP by the network operator during registration at the headend, i.e. the network participant has no influence on this process. Apart from the IP address used by the cable modem when active on the cable network, additional information is transmitted such as the cable network operator's gateway into the Internet or the time server.

Since this assignment via DHCP from the cable network to the cable modem is mandatory, it is not necessary to configure the DHCP client. Current assignments can be read at any time in the Status/DHCP client status menu.

The DHCP server

As a DHCP server, the ELSA MicroLink Cable can manage the IP addresses in its TCP/IP network. In doing so, it passes the following parameters to the workstation computers:

KIP address

KNetwork mask

KBroadcast address

KDNS

KNBNS

KDefault gateway

KPeriod of validity for the parameters assigned

The DHCP server takes the IP addresses either from a freely defined address pool or determines the addresses automatically from its own LAN IP address.

ELSA MicroLink Cable