- — 27 November, 2007 10:25
- Always on connection
- Price factor
- Types of broadband
- Business broadband
- Static and Dynamic IP addresses
- Sharing broadband across multiple PCs
- Running a server on your computer
- Questions to ask the ISP
What modem should I choose? (ADSL)
External ADSL modems are available with two network interfaces: USB or Ethernet. USB compliant modems allow users to connect the modem to their PC via a USB port, while Ethernet-based modems connect up via the PC's Ethernet port. (Note: users will also need a network card to support an Ethernet modem).
While your choice of modem will affect the cost of your ADSL installation, modems can also play a surprisingly influential role in the security of your high-speed connection. Some ADSL modems for example, offer additional features, such as built-in firewalls or PPPoE clients.
If you are going to bring your own modem, be wary that ISPs will not let you use any old modem; you will need to buy a product approved by the ISP. This will also mean that your modem will not be covered by any warranty from the ISP. In addition, some ISPs, including Telstra, will not allow you to bring along your own modem -- you will only be able to get the modem available at the time of installation.
Another thing consumers should be aware of is that not all ISPs offer modems with their services -- and in some cases, the use of the modem is on a rental basis. This means that if you want to cease services with one ISP and join another before your contract is up, you will be expected to return the modem to your original ISP. Make sure you check the conditions of modem use before signing up to any plans.
Before we leave this point, it is important to stress the importance of the modem as a security measure. If possible, do not skimp on the modem. Security is a big issue with broadband (see Security) and if you install a modem with an in-built Firewall -- and there are many available today, you are cutting down the risk to your information from the outside world considerably.
Once the modem is connected and you have confirmation from your ISP that the service has been connected at their end, install the software, enter your username and password through the PPPoE client (see glossary for more details) and you're online.
PPPoE (Point-to-Point Protocol over Ethernet) is a specification for connecting multiple computer users on an Ethernet local area network to a remote site through a modem or similar device. This client is used by ADSL service providers to authenticate their customers on the network.
During an initial exchange between the PC and the remote site (or ISP), the PPPoE client learns the network address and allocates the dynamic or random IP addresses assigned to a user each time they authenticate to a broadband service. When an Internet session ends, that IP address goes back into the pool and gets allocated to someone else.
As the PPPoE client is a generic program, users do not have to stick with the client packaged alongside their broadband service. A list of PPPoE clients can be obtained by doing a Google search. Some PPPoE clients are listed here.
Unlike dial-up connections, DSL and cable modem connections are "always on". Since a number of different users are sharing the same physical connection to the remote service provider, a method is needed to keep track of user traffic, including which user should be billed. Once a session is established between an individual user and the ISP, the session can be monitored for billing purposes.
Because it is similar to the client used for dial-up, PPPoE clients are exposed to the same amount of vulnerability to attack.