Dns Name Resolution; Internet Access - DETEWE OpenCom 510 User Manual

Install the TCP/IP network protocol
and a Web browser for every work-
station which is to have access to the
OpenCom 510 network features.
For notes on installing network
cards, refer to Connection by Network
Card (LAN) on page 75.

DNS Name Resolution

In a serverless LAN, the internal DNS
name resolution is performed by the
OpenCom 510. If you type the string
"host.domain" into your browser, a
DNS request is sent to the
OpenCom 510 IP address. The
OpenCom 510 responds with the
correct IP address, so that the Con-
figurator home page can be called
up.
In a peer-to-peer network (Windows
network), the workstations each
have a name which is displayed in
the network environment. These
NetBIOS names can differ from the
DNS names assigned to the worksta-
tions by the OpenCom 510. The
OpenCom 510 is not visible in the
network environment.

Internet Access

If access to an ISP has been config-
ured on the OpenCom 510, the
OpenCom 510 can be operated as an
Internet access server without any
additional configuration of the
Configuration Examples
workstations. When you want to see
a Web page, you simply type the URL
(uniform resource locator; Internet
address; "http://...") in your browser.
In a serverless LAN, the
OpenCom 510 is configured as a DNS
server and default gateway. The
workstation therefore sends its In-
ternet connection request to the
OpenCom 510.
In almost all cases, the request will
contain a DNS name which is un-
known in the internal network.
When you type a URL into your
browser, the OpenCom 510 receives
the request to find the correspond-
ing IP address. If the name is un-
known in the LAN, the request is for-
warded to an ISP's external DNS
server.
Note: Workstation PCs automati-
cally add a domain name to URLs
without a dot. You specify this do-
main name in the Configurator. For
example, if you have configured
"firm.co.uk" as the domain name, an
access request for "www.firm.co.uk"
will be interpreted as a local DNS re-
quest which does not lead to the es-
tablishment of an Internet connec-
tion. For this reason, you should
choose a name which is not used in
the Internet as the domain name
("firm-opencom.co.uk" for example).
OpenCom 510 in a Serverless LAN
89