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Internet Connections Introduction For you to be here, you must have some access to the internet, but do you know much about your connection, choosing a connection, or what the difference between your's and your friend's connection is? This page attempts to address some of these issues, so you can make an informed choice.

Speeds Speed is the most important thing right? Well, in an uncontented (below) and unlimited world, speed is probably all it would come down to, these "limits" will be discussed later on, but let's discuss what speeds could be achieved by various connections. Big B or little b? An area of mass confusion, is what is MB what is mb? Well, the significance is in the case of the b/B! If the B is uppercase, that means byte, if the b is lowecase, that means bit, the difference being, their are 8 bits in a byte, so 1MB/sec is the same as 8mb/sec. Most speeds are advertised in their bit speed, i.e. 1mbps/256kbps, all with small bs, although some people, even ISPs, confuse the meaning. Speed Table Technology

Typical Speed

Maximum Speed

56K Modem

48kbps

56kbps

ISDN

Single Channel: 64kbps Dual Channel: 128kbps

Same as Typical

ADSL

1-2mbps

8mbps

ADSL2+

not in use

25mbps

SDSL

1-2mbps

3mbps

Cable

2mbps

8mbps

Wireless

1mbps

12mbps 56K Modem

This is the original method most of us used to connect to the internet. It's limited to below 56kbps because of what the line can handle. This technology works by converting digital signals from your computer into a signal for the phone line, using a modem, at the other end, it's converted back again.

ISDN - Integrated Services Digital Network This was the faster option available to many dialup users, with a guaranteed connection of 64 or 128, depending on the number of channels used. A line was typically split into 2 channels, and you would either use both for data, or one for data and the other for simultaneous voice.

DSL - Digital Subscriber Line This category of technologies are currently the fastest available right now. DSL is the superset of many technologies, where data is transmitted down your normal copper line as digital signals, because voice uses a different frequency, you can do both at once, splitters at either end split the voice and the data into separate streams. DSL technologies have a limit on the distance between the premises and your local telephone exchange, which is usually between 3KM and 5KM depending on the speed of the service you are applying for. ADSL - Asymetric Digital Subscriber Line Often simply referred to as DSL in America, this method has a different upload and download speed, the download speed is usually much faster than upload, and is therefore ideal for the home user. It usually starts at about 256kbps rising all the way upto 8mbps in some areas, which in theory is the maximum. ADSL2+ Probably able to carry upto 25mbps downstream, this is a new technology being trialled in some areas. SDSL - Symetric Digital Subscriber Line This method has the same upload and download speed, and so therefore the maximum download must be lower. This is more common for business use, or dedicated gamers, as the speed with which you can send data is faster than that of normal ADSL. Cable This system uses a mixture of fibre optics, and coaxial cable to your home, not your existing phone line, therefore the technology must be available in your area. Wireless This system uses radio technology, and a receiver based on your premises, depending on the technology, the receiver may be attached to your roof or inside the home. The speeds above were based on the UMTS TDD standards, in use by a UK wireless network (provided by Hong Kong).

Limits Except for Dial-Up and ISDN, many of the above technologies have limits which can leave your speed much lower, and in theory, lower than dial up speeds!

Bandwidth Limits The first of the limits is how much data you are allowed to download per day or per month. This is usually specified in GBs, and is common on cheaper services for 1GB a month, mid range services 15GBmth, or 1GBday, and unlimited on the premium services.

Contention Contention is when you and other users are contending for the same line or server etc... for data. It is often expressed as a ratio, such as 50:1 meaning 50 people are sharing the same bandwidth. DSL Contention Here we need a quick idea of how your data gets to your ISPs server: 1) Down your phone line to your exchange. 2) Your exchange into telcos network. 3) Your telcos network to ISP. From your telephone line, to your exchange, there is just 1 user, yourself, here there is no contention, you can send and receive data at the fully specified level. The telephone company will have many users on one exchange, and its at the exchange your data is split between voice and data. The data is then sent down a network cable from the exchange, into the telephone company's network. This is where the first contention comes in, the line may only be, for example, 4mbps. If your ISP says you can have 1mbps, with a 50:1 contention, then a maximum of 200 people may exist on this exchange, if they are keeping to their promise. This is not feasible, and the line is probably capable of a higher data rate, and there will be many lines, but the ratios still exist. If the ratio is anywhere near being met, the telephone company will most likely update the exchange. From the telephone company's network, to your ISPs, there will be another contention, and this depends on the size of the bandwidth your ISP is willing to buy. This will usually not be a problem. Cable Contention Contention on cable is usually between you and the fibre optic network, this depends on how many people are using the bandwidth in your area, for example, if the whole street is downloading a movie, it will slow down, as you're all on the same "cable". Wireless Contention

Contention on a wireless system can take a few forms. Data must travel from your transmittor, the the local receiver, then from the local receiver, to the ISPs network. The bandwidth is limited between your transmittor and the local receiver, but this can be improved by using multiple carriers at the receiver, the data is likely to travel from the receiver into the network by a normal network or fibre optic medium.

What is an IP address? An Internet Protocol address is a unique 32 bit (4 byte) address each computer on the internet must have, it's an identifier for each computer, and is the way of sending and retrieving data. Most dial up users are assigned a new IP address each time they dial up to the internet, the address will depend on the range of the ISP, this is a dynamic IP address. Permanent connections such as DSL are most likely to have a static IP address. An IP address looks like this: 205.45.62.124 Each of the numbers can be in the range 0 - 255. There are a possible of 4228250625 unique IP addresses.

What is my IP address? Your IP address at present is: 220.226.12.24

How do you know this? Your IP address is sent to the server when you make a HTTP request, each server connected to the internet can see this IP, and is their way of sending you a reply. IP addresses are also visible in all e-mails you send.

How else can I find my IP address? If you are using a HTTP proxy, the IP address above will in fact be false. In windows 95,98 and ME > start, run, type winipcfg and hit enter. In windows 95,98,ME,NT (win2k,XP) run ipconfig from a dos prompt. To start a DOS prompt, start, run and type command.com, hit enter In windows 2k, try right clicking dial up connection, select status, and view your IP there.

What can someone do with my IP address? Not much! If you are on dial up, your IP will refresh during next connection. But a user can use your IP to trace your ISP, they can also attempt to connect to any server running on your PC. So if no server is running, and all ports are closed, nothing is going to happen. It is also possible for them to attempt to access open ports, view the security sectio

What are cookies? A website can tell a browser to set a cookie, then according to the browser type, they are stored on your hard drive, for example Netscape saves all cookies in a cookies.txt file, Internet Explorer saves all cookies as small text files in one folder, c:\windows\cookies\ . Cookies can store any limited information a website wishes. Cookies are set a expiry date, the date they will be deleted, when a website deletes a cookie, it sets an expiry date in the past.

Common uses for Cookies Cookies are often used for storing passwords so you don't have to type them in every time you visit a page, they also store information you have used before. Have you ever used a site like "My Yahoo!" or "My...", those that let you customise the content? You may have noticed if you clear your cookies, all your custom settings reset, this is because this custom information is stored in cookies.

Advertising Cookies Cookies may also be set by advertisements on a page! Just before the ad image is loaded, it sets a cookie with information about your site visit, and whatever else the company wishes to note about you. Companies may use this information to help target specific groups, it also lets them trace your visits around the web by viewing cookie data.

How to see when advertisers are using Cookies? In Internet Explorer, A little icon will appear in the bottom right, with a red exclamation mark. If you click this, it will tell you about 3rd party cookies, and who it is.

Disabling Cookies In Internet Explorer 6, tools>>internet options>>privacy. Sliding the bar will show you how each privacy settings deals with cookies. When you are satisfied, select apply then hit ok. In Internet Explorer 4 or 5, tools>>internet options>>security. Select Internet, click custom level... . Scroll down to Cookies, and select Disable. Remember Some sites such as Yahoo! Chat require cookies, selecting "Prompt" may be more appropriate. In Netscape, edit>>preferences, select advanced. Check "Disable Cookies" and press OK.

Deleting Cookies Click Here

Who can view the Cookies? When a cookie is set, data is set to tell the browser which domains may view the cookie,

and when you visit a site which may view the cookie, it is sent this data by the browser, there will be some scripts on the server to get the information from this cookie.

Does Freddy's Utilities Plus use Cookies? No. Only the administration features of this website require cookies, which does not apply to normal site users, we don't allow sites we advertise to set cookies.

Microsoft Virtual Machine: (1) Start, Run. Type "wjview" and press enter. The top line shows the version. If you get an error, you don't have Microsoft's Virtual Machine. Sun Java: Start>>Settings>>Control Panel. Doube click the Sun Java icon, select about.

Where can I get VM? Microsoft (Current version: 5.0.3810.0): Update: Part of Windows Update Install: No legal form of installation over the net, but Try Here or Here. Sun Java (Current Version: 1.5.0): Update And Install: Sun Java

I don't have Virtual Machine, why not? Windows XP users may not have Microsoft Virtual Machine (VM) installed because it was believed that the users could do without this piece of software, but users still need VM for those websites with java applets such as Yahoo! Chat. Windows XP no longer has Microsoft Java Virtual Machine through Service Packs. All other users will have Virtual Machine. See above for download locations.

Square, Circle and Triangle This indicates a corrupted Virtual Machine installation, either Sun or Microsoft. Whichever you use, use the above links to get a fresh version.

Disable - Enable Sun Start, Settings, Control Panel. Click Internet Options. Under the Advanced tab, find the "Java (Sun)" heading. Check the Box underneath to Enable, Remove the check to disable. Close all Internet Explorer windows to make it have effect. Microsoft will automatically disable/enable at the same time.

What is Java Virtual Machine Those programs written in languages such as Pascal or C are compiled into executable files ready to be run. They are OS dependant, IE one written for Windows wont run on Linux. Languages such as Basic are interpreted each time they need to be executed on the users computer. Java is different, first byte code is produced, then when its ready to be executed, they byte code is interpreted. Java Virtual Machine is the software which interprets this byte code and runs a java program. The java applets will not run without a virtual machine. Java applets are not dependent on one OS, making it a very useful language to write it, as the same code may work over many different computers.

Sun Microsystems or Microsoft? Supposedly they should be compatible, but please be aware Sun are the original producers of Virtual Machine. They are however, not compatible due to Microsoft technologies being different. Some applets are distributed in a way which only Microsoft Virtual Machine will run, therefore the Sun version does not work. You can have both versions of Virtual Machine installed on your computer. The control panel with the sun version lets you switch between it being default and not. You can also set which one is used by these options in Internet Explorer: Tools>>Internet Options, select advanced tab. Scroll down to Java (Sun). Placing a check by "Use Java 2...." will make Sun be the Virtual Machine to be used.

Sun v Microsoft Due to a legal battle, Microsoft no longer distribute VM by Install On Demand (IOD). Microsoft are granted the rights under their license to perform updates to, and distribute VM for a limited period, under certain agreements. Sun seeks to make Microsoft issue VM as part of windows or internet explorer, and not as separate web downloads. Sun also seek for their own plugin to be distributed with Windows and internet explorer. Sun believe they are protecting users from outdated microsoft java technology.

Update: Extended License Microsoft and Sun came to a joint decision to allow Microsoft to continue supporting and fixing security problems in Microsoft's VM until September 2004. This is to allow for developets to transition their Microsoft dependent Java code to the standard Java code. Sun will have agreed to this to protect Java - a sudden inability for people to run some java applets could destroy the platform. If you use Sun Java (I recommend), and a applet wont run correctly, I suggest you get on to the service provider, they only have that 9 months to fix, before people really start having trouble - Microsoft VM redistribution is illegal.

Further Extensions Microsoft and Sun came to further decisions to prolong the transition period. Microsoft

may now support the Microsoft Java Virtual Machine software until December 31, 2007. This means security holes may be fixed as found, leaving a much more secure, longer transition time. As has been since 1997, no improvements or changes to the way the Java in the MSJVM works will be made, all that's ever changed in the last 7 years, and for the next 3 years is security holes.

How To Release and/or Renew IP Addresses on Windows XP | 2000 | NT From Bradley Mitchell, Your Guide to Wireless / Networking. FREE Newsletter. Sign Up Now! Follow these steps to quickly release and/or renew the Internet Protocol (IP) address of a computer running Windows XP, Windows 2000, or Windows NT. Difficulty: Easy Time Required: seconds

Here's How: Click the Start menu button on the Windows taskbar. Click Run... on this menu. If the computer is holding a current IP address, type 'cmd' (without the quotes) in the text box that appears. A command prompt window appears on the screen. Type 'ipconfig' (without the quotes) to view the status of the computer's IP address(es). Sponsored Links

Wireless NetworkingShare your knowledge and learn from your peers. Visit the IT community.Networking.ITtoolbox.com Block/Change IP AddressesAnonymous and Secure. Fast & Easy Setup. Free Dynamic DNS from No-IP.www.No-IP.com The Complete IP SiteTrace IP, trace email, hide IP, change IP, proxy test, blocklistswhatismyipaddress.com If the computer is holding a current IP address, type 'ipconfig /release' to let go of the address.

Type 'ipconfig /renew' to obtain a new IP address (whether or not the computer is holding a current address).

Tips: If it is not necessary to view the current IP addresses on a computer, simply type 'ipconfig /release' or 'ipconfig /renew' (without the quotes) in the text box that appears in Step 3. To bring a computer back onto the network after moving it to a different location, or experiencing an unexpected outage, first release, then renew the IP address. Computers on DHCP networks often (but not always) re-establish network connectivity automatically.

How To Release and/or Renew IP Addresses on Windows 95 | 98 | ME From Bradley Mitchell, Your Guide to Wireless / Networking. FREE Newsletter. Sign Up Now! Follow these steps to quickly release and/or renew the Internet Protocol (IP) address of a computer running Windows 95, Windows 98, or Windows ME. Difficulty: Easy Time Required: < 1 minute

Here's How: Click the Start menu button on the Windows taskbar. Click Run... on this menu. Type 'winipcfg' (without the quotes) in the text box that appears. A new window appears on the screen. The "IP Address" field shows the current IP address for the default network adapter. If the computer is holding a current IP address, click the Release button to let go of the address.

Sponsored Links

Anonymous IP AddressLearn about anonymous IP addresses at the leading IT community.Security.ITtoolbox.com Small Business WirelessSimplify your SMB voice and data networks & save.www.Nortel.com Wireless NetworkingFind wireless networking articles at the UK's leading IT resource!Techworld.com/Wireless Click the Renew button to obtain a new IP address (whether or not the computer is holding a current address).

Tips: If it is not necessary to view the current IP addresses on a computer, simply type 'winipcfg /release' or 'winipcfg /renew' (without the quotes) to save a step in the process. To bring a computer back onto the network after moving it to a different location, or experiencing an unexpected outage, first release, then renew the IP address. Computers on DHCP networks often (but not always) re-establish network connectivity automatically.

What You Need:

The 7 Layers of the OSI Model The OSI, or Open System Interconnection, model defines a networking framework for implementing protocols in seven layers. Control is passed from one layer to the next, starting at the application layer in one station, proceeding to the bottom layer, over the channel to the next station and back up the hierarchy.

Appl icatio n (Lay er 7)

This layer supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers, e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer.

Prese This layer provides independence from differences in data representation (e.g.,

encryption) by translating from application to network format, and vice versa. The

ntati presentation layer works to transform data into the form that the application layer can on accept. This layer formats and encrypts data to be sent across a network, providing (Lay freedom from compatibility problems. It is sometimes called the syntax layer. er 6) Sessi on (Lay er 5)

This layer establishes, manages and terminates connections between applications. The session layer sets up, coordinates, and terminates conversations, exchanges, and dialogues between the applications at each end. It deals with session and connection coordination.

Tran sport This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. It ensures complete data (Lay transfer. er 4) Netw ork (Lay er 3)

This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing.

Data Link (Lay er 2)

At this layer, data packets are encoded and decoded into bits. It furnishes transmission protocol knowledge and management and handles errors in the physical layer, flow control and frame synchronization. The data link layer is divided into two sublayers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. The MAC sublayer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame synchronization, flow control and error checking.

Physi cal (Lay er 1)

This layer conveys the bit stream - electrical impulse, light or radio signal -- through the network at the electrical and mechanical level. It provides the hardware means of sending and receiving data on a carrier, including defining cables, cards and physical aspects. Fast Ethernet, RS232, and ATM are protocols with physical layer components.