Policy Based Routing; Bridging - ELSA LANCOM Office Manual

R38 Technical basics
constantly updated and be accessible all over the world at any time. DNS servers holding
long tables containing IP addresses and domain names exist for this purpose.
If a computer calls up a home page from the intranet, it first sends out a DNS request:
"Which IP address belongs to www.domain.com?" If the router has been specified as the
DNS server in the workstations, the request is handled as follows:
Initially the router checks whether a DNS server has been entered in its own
settings (in ELSA LANconfig in the 'TCP/IP' configuration section on the 'Addresses'
tab or in the /
server and retrieves the information required.
If no DNS server is entered in the router, it will attempt to reach a DNS server over
a PPP connection (e.g. from the Internet provider) to get the IP address assigned to
the name from there. This can only succeed if the address of a DNS server is sent to
the router during PPP negotiation.
If no connection exists, the default route is established and a search is then carried
out there for the DNS server.
This procedure does not require you to have any knowledge of the DNS server address.
Entering the intranet address of your router as the DNS server for the workstation
computers is sufficient to enable you obtain the name assignment. This procedure also
automatically updates the address of the DNS server. The router always receives the
most current information even if, for example, the provider sending the address changes
the name of his DNS server or you change to another provider.

Policy Based Routing

Policy-based routing describes a process in which particular data packets are given
preferential treatment. This requires evaluation of a special field within the IP data
packet, known as the Type of Service (TOS) field. This preferential treatment of a number
of data packets can, for example, simplify the configuration of the router via the WAN
when large data volumes are to be transferred simultaneously.
You can find more information on policy based circuit routing in the 'Description of the
menu options'.

Bridging

A bridge connects two or more LANs in such a way that they appear to be a single large
network. When bridging via cable modems, the LAN of the cable network operator with
the headend is on one side and the LAN of the network participants with the cable
modem and the local workstations on the other.
ELSA LANCOM Office
Setup/TCP-IP-module
menu). If it finds one it connects to this
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