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BroadbandTable of ContentsBroadband Internet AccessBroadband Internet access, often shortened to just "broadband", is high speed Internet access—typically contrasted with dial-up access over modem. Advantages of Broadband over Dial-UpDial-up modems are generally only capable of a maximum bitrate of 56 kbit/s (kilobits per second) and require the full use of a telephone line, whereas broadband technologies supply at least double this speed and generally without disrupting telephone use. Things to be Aware ofIn practice, the advertised bandwidth is not always reliably available to the customer; ISPs often allow a greater number of subscribers than their backbone connection can handle, under the assumption that most users will not be using their full connection capacity very frequently. This aggregation strategy works more often than not, so users can typically burst to their full bandwidth most of the time; however, peer-to-peer (P2P) file sharing systems, often requiring extended durations of high bandwidth, stress these assumptions, and can cause major problems for ISPs who have excessively overbooked their capacity Traffic ShapingTraffic shaping provides a mechanism to control the volume of traffic being sent into a network (bandwidth throttling), and the rate at which the traffic is being sent (rate limiting). For this reason, traffic shaping schemes are commonly implemented by ISP's when users go over their limits or user P2P downloading. Peer-To-PeerPeer-to-peer (P2P) traffic is particularly troublesome for traffic shaping efforts for ISPs because it is designed to use any and all available bandwidth which impacts QoS-sensitive applications (like online gaming) that use comparatively small amounts of bandwidth. Most, if not all, popular P2P applications are location-agnostic [citation needed](they care not/little if they download from a user halfway around the world or one next door) makes them even more problematic, as traffic outside of a network, which is the more expensive kind, will increase. This has given P2P a bad reputation with internet service providers trying to roll out quality-dependent services (again, like VoIP). Some may even view P2P as an 'attack' on their networks[citation needed]. However, P2P is often listed as the reason subscribers choose broadband internet. What is the Difference between Cable and ADSL?Cable uses the coaxial cable used to provide pay TV for either Foxtel/Telstra or Optus respectively. It allows for speeds up to 10 megabit per second (approx 1 megabyte a second) download (internet to you) speeds. Telstra and Optus are the only providers, and which one you can get depends on what is installed on your street or in your building. xDSL - either ADSL or SDSL - Asymmetric/Symmetric Digital Subscriber Line - uses an existing phone line to provide internet access at high speeds, while still allowing the phone line to be used for phone calls/faxes. It does this by transmitting data at very high frequencies, compared to how a regular modem works. Unlike a regular modem which dials in to the ISP, xDSL is always connected as long as the modem is switched on. ADSL is the most common form of broadband, as it doesn't require special cables built into the street or building, but runs over regular phone lines. What is Rapid Transfer Churn?This applies to ADSL only. Rapid Transfer or Churn refers to the ability, if your chosen ISP supports it, to switch to another ISP very quickly (in the order of a day or two). For example, it's common for people to find that their provider either doesn't provide the services they want, or find that another ISP has a plan better suited to them. In these cases, they just call the ISP they want to switch to, and that ISP can switch them over within a couple of days. It does require you pay your old ISP any bills owed to them, however. Both ISP's must support the "Churn" process for this to happen. Broadband Choice indicates which ISPs support Churn. What the Difference between Static and Dynamic IP?An IP (Internet Protocol) is the address of your computer or Gateway/Router when it's on the Internet. Most broadband companies supply a Dynamic IP - which means the address is different every time you connect, unless stipulated. Most dialup connections work this way too. Some people use broadband to run private or public servers, usually for business, but sometimes for people who run a server for friends to access, such as for games, web serving or similar. These people want their internet address to stay fixed with the same numbers all the time, so people know how to access their server. This is called a Static IP address whereas Dynamic changes every time you login or within a specified time stipulation. Advantages of Static IP over DynamicSome people use broadband to run private or public servers, usually for business, but sometimes for people who run a server for friends to access, such as for games, web serving or similar. These people want their internet address to stay fixed with the same numbers all the time, so people know how to access their server. This is called a static IP address. People with static IP's may have a domain name (eg: www.DomainName.com.au) linked to their IP address. If the IP address changed whenever they logged off or once a week or had to turn their modem off, it would make it difficult for people to find their server because their assigned external IP address would change. This issue can be avoided by using a dynamic dns or DDNS service providers however a static IP is more advantages when VPNs, web sites, FTP sites and so forth because there is one less step in setting up and one less thing to go wrong therefore proving more reliable for mission critical servers. Static IPs make firewall rules easier to write, so that remote private servers could be configured to let only your IP in. The downside is if you are likely to accumulate enemies on the internet, you might leave yourself open to internet-based attacks as users with dynamic IPs can find it easier to hide. What is the difference between an Ethernet and USB modem?Dial-up modems connect to your computer via a chunky 9-pin (traditionally) port. DSL modems connect via ethernet RJ45 (looks like a larger version of a phone plug) or USB (generally a long flat hollow-looking plug). Most computers produced over the last 2-3 years will have both an ethernet and a USB port (if you've got any Mac younger than an iMac, it will definitely have USB and ethernet). Ethernet is how computers connect to each other over a network. It is an older, very stable connection method. USB (Universal Serial Bus) is newer and more traditionally used for connecting hardware such as printers, keyboards, mice, cameras, and so on. It can be less stable than ethernet but its advantage is that in the most basic of ADSL modems, you do not require a separate power cord. Most people tend to recommend ethernet modems for connecting as it is less temperamental and easier to install, which makes connection troubleshooting much simpler. Ethernet modem/routers operate independently of your computer and functionality doesn't depend on which OS you run on your computer. Do I need a multiport modem?You will require no more than one port ("port" is the "ethernet plug" on the modem) if don't want to run more than one node (computer, print server, or device with its own IP address) on a network. And even if you do decide to add extra computers some time in the future, a hub or these days switch (much like a power board for networks) can be plugged in at a later date. So if a single port Modem/Router is in the plan it is easy to solve. If, however, you end up with a multi-ported modem because it was cheap or supplied by the ISP, it certainly won't cause any problems. What is the difference between a Modem/Router/Switch/Wireless Access Point?To understand the difference between a modem and a router, you need to understand several different, but related, devices. The individual devices are (1) an ADSL modem; (2) a router; (3) a switch; and (4) a wireless access point (WAP). It becomes confusing because there are combination devices which can combine both an ADSL modem and a router in the one case as well as devices which can combine an ADSL modem, a router and a switch all in the one case! What is an ADSL modem?An ADSL modem is a device that transmits and receives data over the plain old telephone system's (POTS) analogue lines. It allows your PC to connect to your ISP using the Internet Protocol. The modem acts as a "bridge" between your PC and your ISP. The dynamic or static public IP address which your modem obtains from your ISP is passed on to your PC. Your ADSL modem forwards packets based on hardware level MAC addresses between your ISP's router (and the Internet) and your PC. What is a Router?A router is a device which acts as an interface between two networks. It forwards packets based on network level addresses (Internet Protocol addresses in this case) between your ISP's router and either your LAN or your single PC. A router learns more about the networks to which it is connected and can be more selective about the packets it passes on. A router rejects packets unless they match predefined attributes (eg specific protocols or destination network addresses). A router can also select the best route for packets to take in large interconnected networks. For a more detailed look at how routers work, check out this link at the How Stuff Works web site. What is a Switch?An Ethernet/LAN switch creates a virtual network between two networked devices for the duration of the data transfer. This is unlike a hub which forwards all received data to all connected devices, even though the data may be destined for just one of those devices. A switch learns the association between the MAC addresses of connected devices and its switched ports. By sending data only to where it needs to go, a switch reduces the amount of data on the network, thereby increasing the overall performance of the connected devices. A switch also improves security, since data is not broadcast to every connected device, but only to the device for which it is destined, it cannot be monitored by other connected devices. For a more detailed look at how switches work, check out this link at the How Stuff Works web site. What is a WAP?A Wireless Access Point (WAP) is a 'base station' device that connects a wired Ethernet network to a wireless network (WLAN) comprising one or more wireless devices. While very small WLANs can function without a WAP in "ad hoc" or "peer-to-peer" mode, WAPs support "infrastructure" mode which bridges WLANs with a wired Ethernet network and also scales the network to support more clients. There a few different types of WAP: (1) Bridges ? connect devices that all use the same kind of protocol; (2) Hubs ? provide networking connections to a variety of clients and add features like roaming; (3) Routers ? connect networks that use different protocols; and (4) Gateways - provide additional features such as NAT, DHCP servers and firewalls. The Combined Approach ...Some ADSL modem manufacturers have started adding features to their modems which are normally only found in routers or combined ADSL modem/routers. Such features include:
Pluses and minuses of the Combined ApproachPluses for the combined modem/router and modem/router/switch devices are that you only have to find a home for one plugpack, you do not lose half your desk space to three new boxes and that there are fewer cables for you to have to hide out of sight or otherwise manage. Minuses for the combined approach is that if any one of the devices in the combined unit malfunctions, you will have to return the whole unit to the manufacturer or, if your unit is no longer under warranty, you will have to replace the whole unit. You might find this a little inconvenient. It may also be more expensive to replace a combined unit than replacing an individual device. If you want to replace one of the devices (eg upgrade your modem to ADSL2+, upgrade your WAP to 802.11g etc), you have to replace the whole combined unit which, again, will generally be more expensive. It may also be more difficult to troubleshoot an all-in-one device - with separate units you can physically remove one or more from the equation and isolte the problem more quickly. Line Filters and SplittersWhy do I need a Line Filter or Splitter?When ADSL is activated on your telephone line it uses very high frequencies that can interfere with your normal telephone service. Any other device on the same line such as a telephone, fax or answering machine needs a line filter or splitter. It should be noted that some standalone facsimile machines do not work well with any inline microfilter, regardless of brand. In such situations, the only solution is to use a central filter. Which type of filter do I need?
Problems receiving (not sending) faxes on an ADSL lineA Canon FAX-B150 can send faxes with no problems, but is unable to receive faxes on an ADSL-enabled telephone line. Also connected to the line was a D-Link DSL-300 modem with a D-Link 10MF inline filter. The filter was attached to the fax machine. The problem was solved by using a D-Link 10-CF Central Filter to split the line as well as a D-Link 10-MF inline filter in series on the line before the fax machine. How to Choose the Right Broadband Plan?The best way to choose the right broadband plan is to use Whirlpool's Plan Finder. Make sure you cover all the points covered in this article and you will be well informed to choose the best plan to suit your circumstances. All text is available under the terms of the GNU Free Documentation License |