Siemens OZS164 SERIES WEB SERVER Commissioning Instructions page 100

DoS attack
DSL
DSL router
Dynamic DNS
Dynamic Host
Configuration Protocol
Dynamic IP address
DynDNS
Ethernet
Firewall
Gateway
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Siemens
Building Technologies
A DoS attack (denial of service) is a special type of hacker attack on computers
and networks connected to the Internet. The DoS attack aims at disabling
computers and networks to prevent network resources from being provided and
services from being executed.
DSL is a type of data transmission allowing for 1.5 Mbps access to the Internet on
standard copper phone lines. The Internet Service Provider ISP provides the DSL
connection. You need a DSL modem for this type of connection.
The DSL router has several functions. It connects the Ethernet network (LAN) and
the internal network devices to the Internet. The router then requests the IP
addresses for the internal network devices from the DNS server. Port forwarding
(NAT, PAT) is also configured in the router. In addition, service "DynDNS", which
automatically is updated after a change of the DynDNS server, is activated in the
router.
See DynDNS
See DHCP
A dynamic IP address is assigned automatically via DHCP to a network device. As
a result, the IP address for a network device differs every time the device logs in or
at periodic intervals.
The ISP assigns dynamic IP addresses to network devices that are not online
continuously, i.e. integrated in the network. Dynamic IP addresses are reassigned
to other devices, as the number of addresses is limited. Web server (permanently
online) does not use a dynamic IP address.
The DNS server assigns domain names and IP addresses. Dynamic DNS
(DynDNS) is needed for dynamic IP addressing. It allows deployment of a network
device with dynamic IP address on the Internet.
DynDNS ensures that a service is always available on the Internet under the same
domain name regardless of the current IP address.
www.dyndns.org is a free-of-charge DynDNS service. A domain name can be
registered with this provider, e.g. myhome.dyndns.info. The web server can be
reached at http://myhome.dyndns.info.
Ethernet is a network technology for local networks (LAN). Ethernet operates at a
transmission rate of 10 or 100 Mbps and has a maximum range of 100 meters
between two network components.
A firewall protects networks against unauthorized access from the outside.
Firewalls are hardware and/or software measures designed to control data
exchange between the private network to be protected and an unsecured network
(e.g. the Internet).
A gateway is a device connecting networks of different architecture (addressing,
protocols, interfaces, etc.). Although not entirely correct, the term often is used
interchangeably with router.
Web server
Appendix
CE1C5711en
25.08.2010