The material here is aimed at home users in the UK who have decided not to use the USB modem provided by their ISP and find
that they need some settings which are not readily available from the ISP.
Every now and again, someone asks "What do I need to know to set up ADSL Broadband with a router/pci modem etc?"
Here, with acknowledgements to those who have done this before me, (and better!), is my list of settings.
IP - Internetworking Protocol A system for transporting data between computers across networks, including the Internet itself.
TCP - Transmission Control Protocol A protocol that ensures data integrity, used in conjunction with IP.
UDP - User Datagram Protocol Used instead of TCP where the timely flow of data is more important than its integrity, such as
in streaming. Go look up OSI on the www if you want to know more.
IP address An address that uniquely identifies each machine on an IP network. It is commonly given in a
numerical format (such as 192.168.0.1), where each of the four groups of (decimal) digits represents a byte,
so has a value in the range 0 to 255. A DNS server can convert these into friendly names.
StaticIP address An address that is assigned to you, more or less permanently. Useful if you want to have a fixed address on
the web that never changes so that visitors know where to find you, but you'll have to pay your ISP for this.
Also useful on a LAN if you are running any kind of server (smtp, ftp, web) and need to direct
messages to the particular machine hosting the server.
DynamicIP address An address that is allocated for the duration of a connection. By default, most ISPs issue you an address
from a pool, then recycle it when you disconnect. This means that each time you connect, you have a different
address, which can be an obstacle if you wish to run a server from your own machine.
ATM - Asynchronous Transfer Mode A technology used by BT to connect ADSL users to their ISPs.
LAN - Local Area Network A cabling system linking two or more computers. Local implies the use of a technology that is
limited to a few hundreds of metres, i.e. typically within one building. Usually implemented using 10/100BaseT UTP (Unshielded Twisted Pairs) Ethernet.
WLAN - Wireless Local Area Network A LAN that uses radio transmission to make links between computers. Avoids the physical
installation and inflexibility of LAN cabling, but less robust, less secure and more expensive. However, wireless
networking functionality (WiFi - pronounced why-fy to rhyme with HiFi) is now being built into many laptops as standard.
WAN - Wide Area Network A network that extends over a much greater physical extent than a LAN. In ADSL,
it means the network (phone lines) that connects you to your exchange and the equipment there that links you to the
wideband trunk services. A WAN can extend over several kilometres, and conceptually, even between continents.
DHCP - Dynamic Host Configuration Protocol Every machine on an IP network needs an IP address that identifies
it uniquely. If you have several PC's networked together, you can use DHCP to automatically allocate IP addresses
to them within the LAN environment. Your ISP also uses DHCP to allocate you an IP address every time you connect.
A router is often both a DHCP server (to the LAN) and a DHCP client (with respect to the ISP's DHCP server).
DNS - Domain Name System The DNS allows an internet IP address to be represented by a friendly name, such as
www.pipex.com. A DNS server will translate this name into its numerical
equivalent. Your ISP will provide a DNS service to support your access to the Internet.
NAT - Network Address Translation Allows several computers, each with its own LAN IP address, to appear to the ISP as a single machine with
only one IP address. This literally translates multiple addresses between the LAN and the WAN. A good article
on this can be found here.
ICS - Internet Connection Sharing A system included with many versions of Windows software (Win98SE and later) which allows a single internet
connection (usually provided by a modem) to be shared with other machines via a LAN. The PC running ICS can also
provide DHCP and NAT.
USB - Universal Serial Bus A system which allows medium-speed peripherals to be attached to a computer via a simple plug and socket connection.
No need to open the case, and software support is automatic, once installed. Most USB devices can be powered via the USB
connection. Furthermore, USB is not specific to any particular platform, so that if you have appropriate drivers, you
can use USB devices with PCs, MACs, Linux boxes etc (though MACs and laptop PCs tend to be fitted with a similar system called Firewire). USB is
rapidly displacing specialized connections such as parallel printers, RS232 serial ports, serial mouse, serial keyboards etc.
ADSL - Asymmetric Digital Subscriber Line A method of using standard telephone wires to carry broadband. The asymmetric refers to the fact that
the upstream and downstream speeds are unequal. Upstream is typically 256 kbps, whilst downstream can be 256 kbps,
512 kbps, 1 Mbps, 2 Mbps, depending on the depth of your wallet and your geographical location. ADSL is a member of a
family of similar technologies, referred to generically as DSL or xDSL. Have a look at the
IEC's page on this.
DMZ - De-Militarized Zone A router or gateway with NAT hides the various machines that may be connected to it. Sometimes it is necessary for a
machine to be directly accessible to the WWW and not protected by a firewall or NAT. This is referred to as DMZ and may be
useful for servers. However, any machine in the DMZ is vulnerable to attack and should be protected by means of a software
firewall or similar.
HTSE - How To Suck Eggs See above.
Some recommendations
www.adslguide.org.uk provides some useful material of interest to all
ADSL and BB users.
Whilst aimed principally at the cable audience,
Robin Walker's website has many
useful tips and links for networking and BB in general.
Many useful definitions can be found simply by typing, for instance: "define:POP3" into the google search engine.
Did this page help you? Many manufacturers use different names for the same concepts, so I'll welcome being
told about any alternative terms that you find being used.
Please mail me if you have any suggestions for how I could
improve this page.