Internet is not one big network. As the name claims it is inter-net, thus a network connecting networks. This is
important to know as it is the base of the Internet foundation. When you logon to your local Internet provider, you
connect to their network, which is connected to many others. This is the strength of Internet, if one network
malfunctions, the other can function normally without it.
Universal Resource Locator
Most people use the Internet merely for World Wide Web browsing and e-mail. To explain how the Internet works
we will start by using a sample connection between a browser and a server. There are many ways to find an URL to
visit, they can be found in magazines, newspapers, they can be bookmarked or they can be embedded in other
documents as links. However they all consist of the same major parts. Lets look at an URL and sort out what‟s what
in it. We will work with http://www.internet.com, it‟s a site for and about the Internet. The easiest way to understand
URLs is to split them up into part, like this:
Today everyone knows that a text starting with www is a World Wide Web address, this is not completely true.
Actually it is the http:// part of the URL that specifies that we want to connect to the part of the server that handles
the Hyper Text Transfer Protocol although if we try to connect to an address starting with the www prefix our
software assumes it to be http. The http protocol is the Internet standard for exchanging HTML files between clients
and servers. HTML or HyperText Markup Language is the language used to layout pages so they may contain text,
pictures, multimedia and Java among else. In this case we are acting as a client since we are requesting a document
from someone else. Other than http there is also a secure encrypted version of http, called Secure HyperText
Transfer Protocol (https://) and the File Transfer Protocol (ftp://) among many others. So the first part of the URL,
the protocol tells our software how we want to connect to the server and what kind of reply we are expecting.
Next comes the host. A host is a computer that is connected to the Internet. When you use your modem to connect to
your local ISP (Internet Service Provider) or LAN you will also become a host. However only certain computers
have hostnames that works in an URL. If you connect through an ISP you will not get one that can be used in URLs.
Since the communication between hosts is based on IP (Internet Protocol) addresses and the computers themselves
don‟t know where on the net an URL is to be found, they can only say “I want to talk to host 188.8.131.52”. For
this reason we have domains. A domain is a way for us humans to remember a location on the Internet. The
computer must translate the domain into a number in order to make contact to the host.
Top Level Domain
The top-level domains also exist to make it easier for us humans to find our way on the Internet. The tld‟s are
provided so that domains can be sorted into categories and countries. Countrywise they are sorted after a two-letter
country code standardised by ISO. The category domains include top level domains like .com for commercial usage
and .edu for education.
.arpa ARPA specific domains
.com Commercial organisations
.edu Educational institutions
.gov United States government agencies
.int International organisations
.mil United States military
.net Network providers
.org Non-profit organisations
.ad…zw Country specific domains
Domains can be mostly anything, different TLD registrars (the organisation that manages the registry) have different
rules for registering domains and as long as you follow their rules and domain names rules found in RFC 952, 1035,
1123, you are free to use your imagination. (More on RFC‟s later on.)
Domain Name System
Because the hosts only can find each other by IP address in the same way that US Mail needs zip codes to find the
correct receiver, there must be a system to convert our easy to remember URLs to address that the computer can use.
This system is called the Domain Name System (DNS). In the early days of the Internet there weren‟t many hosts on
the net so every computer connected had its own file with all the domains and their corresponding addresses. Today
however with millions of hosts connected this system wouldn‟t be very efficient. When we want to find our host,
www.internet.com, we contact a computer that we do know the IP address of. This server is called our root dns
server. We ask this server where we can find information about .com domains. The dns server then gives us a list of
.com domain name servers. Our computer now selects one of these servers, contacts it and asks it about
internet.com. Just as with the root server we get a list of servers handling that domain. This is how it continues until
we know the IP address of www.internet.com. In general the Internet software is “smart” and remembers common
servers, and can that way skip one or two of the domain name servers, making the communication faster and less
transfers necessary. Now our computer software is ready to make the actual connection to the host.
Transmission Control Protocol
The communication over the Internet is made up of layers. This way many different types of computers can talk to
each other by varying methods. Another feature of it is that every piece of software doesn‟t have to “re-invent the
wheel”, for example, when we use Netscape Navigator in Windows95 to connect to www.internet.com, it will use a
piece of software built-in to Windows95 called Winsock. Winsock will then handle the communication such as send
and receiving data and looking up domains through the domain name system. Our browser will just tell it what to do
and it will do it. Of course it‟s not only browsers that use Winsock, mostly all Windows95 Internet software such as
e-mail clients, ftp clients and newsreaders use it. The same way that Windows95 has Winsock most other operating
systems have something similar that has the equivalent features.
We‟ve been over the application protocol layer, it was the protocol that described how two applications talk to each
other, like how the HyperText Transfer Protocol transfers the html documents used to layout webpages.
Transport protocol layer
Usually when Internet communication is discussed people talk about TCP/IP and how all the information over the
Internet is transferred over it. This is not completely true, although most information goes by TCP (Transmission
Control Protocol) there are others. The applications that are communicating decide which transport protocol they
are going to use based on the standard that is set for the data that is to be transferred. Applications like browsers and
file transfer clients use TCP while transfers that need more speed, like audio and video streaming, at the cost of
reliability use UDP (User Datagram Protocol).
When applications talk to each other over the Internet, like when you look at someone‟s homepage, they do they do
not take part in the actual sending and receiving. This is where the transport protocol layer comes in. The
application tells the transport protocol what to send and where to send it and then in the case of TCP it is up to the
transport protocol to make sure that everything gets sent and that everything arrives in the same state that it was sent.
And if anything goes wrong it is also the transport protocol layer that handles it by re-sending. The transport layer
also splits that data into smaller pieces, if you want to send someone a two-megabyte file, it can‟t all be sent at once,
so the transport protocol layer splits it into smaller chunks.
The Internet Protocol (IP) layer gets the datagrams (the parts of a file that has been split up) from TCP (or whatever
transport protocol that is being used) and adds some of its own information and does the actual logical transfer over
the Internet. Simplified this can be described as if TCP makes sure everything goes through, while IP actually makes
IP only does the logical transfer, this might sound weird but it isn‟t. Since Internet spans over many different types
of networks such as Ethernet and Token Ring which all have their own way of communicating there is a need for a
layer that can work on top of them all. The Internet consists of many networks connected to each other, some
networks might have connections to many other networks while others only have one route out to the rest of the
Internet. It is the Internet protocol‟s job to find out how to move the data between the different networks.
Finding out how to move this data between networks is called routing. Where two networks are connected to each
other there is a router or a gateway, these are used to move data between the two networks. So what IP has to do is
to check if the target computer is in the same network and if so, just send it away. If not it must find out to which
route it should take. For this it uses a routing table, in it there is a list of IP addresses and to what gateway they
should be sent. If there isn‟t an entry for the target IP, it is sent to the default route. The default route is the gateway
that is most likely to be the correct one. When it knows where to send the datagram, it does so and it‟s that networks
responsibility to get the information to the correct computer or onwards to another network.
Networks on the Internet are called subnets, a subnet can also have it‟s own subnets. A large university can for
example be a subnet of the Internet and have subnets for each faculty. The purpose of making small networks it to
stop one malfunctioning hardware device from stopping the entire network. This is a part of the overall Internet
strategy, there should always be a way out. If on connection goes down there is always another. When IP decides if
a host is located within the current subnet it looks at the IP address and analyses it.
All the computers connected to the Internet must have its own IP, and because networks have different size, i.e.
number of hosts, there are different network classes. The system is constructed in such a way that Class A networks
may have many subnets and hosts, while Class B networks fewer, and the class system ranges down to smaller and
smaller classes each with fewer hosts. All the networks connected have been assigned one or two network ranges
from a central authority in which they can decide what computer gets what number. A company that requests X
amount of IP‟s might not have the need for an entire Class B network can then be assigned two or three Class C
networks. The point of not giving out more IP‟s than necessary is due because the Internet is starting to run low on
Ethernet is a very popular and widely spread type of Local Area Network. The most common form of Ethernet is
called 10BaseT, which denotes the maximum transmission speed of 10 Mbps using copper twisted cables. Recent
enhancements of Ethernet bumps the speed to a maximum of 100 Mbps, this system is called 100BaseT.
Physical protocol layer
Ethernet is the physical network. Here we have computers actually connected to each other by cables and wires.
Since IP was made to travel over many kinds of networks, it has it‟s own addressing system, the IP numbers. At the
physical layer of the network, IP addresses do not mean anything, Ethernet and all the other networks have their
own way of finding the correct hosts.
When Ethernet was designed one of the goals was to make sure that two computers could not share the same
address. Because of this every Ethernet network interface card (NIC) sold has it‟s unique Ethernet address
consisting of 48 bits (a bit is either 0 or 1), all the Ethernet manufacturers has to register with a central authority that
is monitoring this.
Address Resolution Protocol
Ethernet works in the same way as a big party line, what one says, everyone hears. But just like you do not listen to
what everyone says on a party line, your Ethernet system will only listens to data directed to it. To find the
corresponding Ethernet address for an IP address (as they have nothing in common), your system will send out a
broadcast to which all the systems on the local network will listen, asking if anyone is assigned to that IP. This
system is called the Address Resolution Protocol, commonly called ARP. When the system that has that IP hears
your request for its Ethernet address, it will reply and the two computers can now talk to each other. It would be
very bad for the network performance if this had to be done every time two computers try to make a connection,
because when it‟s done all other communication is halted. Instead your system will save the information it knows
about other hosts in memory for some time to speed things up.
Putting it all together
You probably noticed that there are many protocols needed for Internet communication and it‟s not always easy to
understand how they work together. We will take a small example as a summary and show what each protocol will
We will again use our browser example, lets say that you have requested a small text document from
www.internet.com and the server sends it over to you (mycomputer.network.se). First of all the server will add
information about what is sent in the HyperText Transfer Protocol, discussed earlier. This will tell your application
what data the packet is containing. Next TCP will take all that information and add it‟s own headers to it and send it
all down to the IP level. IP will also add it‟s own headers, as each protocol layer only understands its surrounding
neighbours. Ethernet will not understand TCP headers and HTTP will not understand IP headers. The IP layer will
now found out how the packet is to be sent, and it‟s most likely through Ethernet so it passes it down to Ethernet.
Once the Ethernet package reaches mycomputer.network.se, Ethernet will remove its headers and send it back up to
IP. IP will the do the same and give the information to TCP. As you can read from its name, Transmission Control
Protocol, TCP check the information so it hasn‟t got corrupt while transferred, if so it asks the server to send it
again. If it‟s all right it will remove its headers and give the information to you browsing software that removes the
HTTP headers and you can now see the text file in your browser!
Past the basics
Internet‟s smart layering system might make it seem as if it is easy for the different layers to perform its actions. For
users and most application developers it‟s both easy to use and develop Internet software as most of the technical
parts of it is built-into modules that can be easily adapted in many programming and application environments.
Behind all of this it isn‟t such a simple matter. As we discussed earlier large files have to be split into smaller pieces
so it can transferred easily. This wasn‟t completely true. Almost everything that is transferred must be split, or
fragmented. Every physical network type has it‟s own limit on how big packages it accepts and if a larger one
arrives it must then handle the splitting and re-assembly, that on packages that might already be split. Sending out
too large packets can then of course make Internet transfers slower as hardware on other places must work, besides
the increased traffic volume this generates.
Internet has many other protocols than the ones we have discussed here so far. ICMP or Internet Control Message
Protocol would probably be described as Internet‟s error reporting protocol. If a packet of data takes too long to
deliver, an ICMP message will be sent to the sender telling what happened. Also if a system tries to transfer some
data to a network outside the local one through the default router and that router has been told there is a better way
to the target, the source will receive a reply stating so. The Internet Control Message Protocol really is what its name
says, a message protocol for reporting errors, it doesn‟t find errors itself.
We talked about UDP, User Datagram Protocol before and we said it was less reliable and faster. It is less reliable
because its headers are smaller and it has fewer features to verify that the information transferred is correct. While
TCP is what is called a connection protocol, in other words both computers talking respond to each other data so
they both know if everything worked, UDP is connectionless. This means that in for example an audio stream from a
live radio show is sent to the listener just like in real broadcast radio. Ready or not, we‟re transmitting now. It‟s
basically up to the listener to make sure he‟s ready to receive. This of course means loss, some data will not reach
the listener and that is what makes is less reliable but faster. UDP itself doesn‟t have any error checking but the
application using the protocol may, it is however then easier to use TCP that has it built-in.
When TCP receives data from IP, it does not directly know how it should be sent to the application layer. Many
Internet applications might be running so there must be a way to find out what application wants what. This is done
by using ports. When we connect with our browser to www.internet.com, our software knows we want to connect to
the HTTP part of the server since we are using the world-wide web (it can also be specified by typing
http://www.internet.com:80). To make sure the server knows we‟re requesting an HTTP document we add the
standardised port 80 to our request. With the request we also add the port we want the server to communicate with
us through, this can be any free port. This way the two computers TCP software can get the data sorted out correctly.
Different types of transferred data uses different ports that are standardised to make sure there are no clashes.
Internet history and organisation
Dawn of internetworking
The groundwork for Internet was created as early as in 1957. That year USSR launched the first satellite, Sputnik.
To establish lead in military science and technology the US Department of Defence formed the Advanced Research
Projects Agency, commonly known as ARPA. Later in the 60‟s, ARPA started to study networks and how it could be
used to spread information. In 1969 the first few networks were connected. The first system to send e-mail across a
distributed network was developed 1971 by Ray Tomlinson and the telnet (allowing users to login on remote
computers) specifications arrived one year later. The first drafts for a networked called Ethernet were created in „73
and a year later there was a detailed description of the Transmission Control Protocol. The Usenet newsgroups were
created in 1979 and in 1982 Department of Defence declared TCP/IP to be standard. At this time the number of
hosts connected was very low, in 1984 it broke the 1000 boundary. Three years later that number had changed to
10000, but we are still far from the Internet explosion.
Most of this all happened before computers were widely spread, IBM released its first PC, based on Intel‟s 8088
processor in 1981. The Pentium processor family that currently is being phased out arrived in 1994. The users
connected to the Internet at this time were researchers and students, connected by university networks.
A worm that infected computers on the Internet with a program that took up system resources (like memory) created
a need for some sort of team that would try to find solutions to make such issues less dangerous. The team was
called Computer Emergency Rescue Team (CERT). They work by writing advisories and reports on how to avoid
What most people tend to define the Internet as, is the web. The World-Wide Web standard was created in 1991 by
CERN and the predecessor to Netscape Navigator, Mosaic saw light two years later. Common people started to get
Internet access in 1994-95, it‟s around those years the numbers of hosts, domains and networks started to increase
rapidly. Yet only a small amount of the earth‟s population is connected.
The so-called browser war between Microsoft‟s Internet Explorer and Netscape‟s Navigator started in 1996 when
the two companies released their 3.0 browsers. When this is being written there still isn‟t a winner but Netscape has
been forced to make its browser free (Microsoft‟s has always been), including the source code. Perhaps the US
Justice Department will prevent Microsoft from giving its browser away, perhaps they will split the company into
pieces. At least it shows the future importance of the Internet when Microsoft embeds its browser into the core of its
Controlling the Internet
When we look into how the Internet is controlled today, we have to have in mind that when ARPA created the
network for more than 25 years ago, they did not intend it to be used the way it is used now, nor did they expect this
amount of users. The managing organisations have been created along the way and there are no exact jurdistictions
on who controls what.
Internet Architecture Board
The Internet Architecture Board, or IAB, is on top of the heirachy. They review the Internet standards, oversee the
other groups, and act to conserve control over Internet as an international network. Their probably most important
role is to identify long term opportunities and how they should be handled.
IETF and IRTF
Almost directly under the IAB we have the Internet Engineering Task Force and the Internet Research Task Force.
The IETF handles all the current protocol standards and promotes further development. IETF also handles operation
and management of the Internet. The IRTF is more of the Internet‟s future department. They take care of all the
future problems of the Internet and how they are to be handled. Among their work is how the net should handles
billions of hosts, faster connections and wireless Internet. For this they have to look at new protocols and how they
can be incorporated into the current system without major service interruptions.
Request for Comments
On the Internet anyone can propose a standard. By writing a text that follows certain guidelines new features and
standard can be proposed to the IETF User Services Working Group for review. If it is approved it will be assigned a
unique number and it will be added to the Request for Comments (RFC) database. The first RFC was published in
April 1969, then as a way to document the network. Today there are thousands of RFC‟s dating from the beginning
of internetworking to present day, many have been outdated by newer ones along the way. The RFC‟s provide a
great potential for the Internet to continue its development as new technologies can be presented quickly and then
Next generation Internet
The current version of the Internet Protocol is version four. Abbreviated it is known as IPv4. When it was created
the amount of computers connected to the Internet was not expected to be as high at it is. The addressing system, the
IP addresses consist of four octets of numbers ranging from zero to 255 (example: 184.108.40.206). In technical
terms this is 32-bits, a bit can be either null or one so this gives us almost 32^2 unique numbers. The actual number
is a bit lower as all combinations are not allowed. This is quite a large amount of computers that can be connected
but in fact estimates show that early in the next century the IP addresses will be exhausted. This is one of the reasons
a new Internet Protocol version is being developed. Formally it is named Internet Protocol Version 6 (IPv6) but it is
also known as IP Next Generation (IPng).
To provide more IP addresses the addresses in IPv6 have been expanded to 128-bit, or approximately
340,282,366,920,938,463,463,374,607,431,768,211,456 theoretically available IP addresses. This is the limit that
the engineers think we will stay below for quite some time.
IPv6 has been designed to enable high-performance, scalable internetworks to remain viable well into the next
century. A large part of this design process involved correcting the inadequacies if IPv4. One major problem that has
been fixed is the routing. IPv6 does not use different network classes for routing instead it uses a system that
provides flexibility to expand networks yet making the routing quick. With many addresses to work with the
addressing has been layed out so they first of all are sorted by their major connection points. One such point is Sunet
in Sweden, there all the major Swedish ISP‟s connect to each other as well as with foreign countries. Each ISP will
then have a large address range that it can provide to companies, minor ISP‟s and dialup customers. This makes
routing much easier, Internet backbone routers will no longer have to have huge databases of over 40,000 entries.
With IPv4 there isn‟t any security at IP level. One of the design goals for version 6 is to provide authentication and
encryption at a lower level. Previously encryption had to be done at a higher level, usually at the application layer.
The authentication part makes sure that the information is actually coming from the source that it is claiming to be.
This ensures that valuable data or passwords that is stored on a system cannot be spoofed (method to change the
source address to make the packet appear coming from a different host) to intruders. Encryption is made by adding
extra headers to the IP packet with encryption keys and other handshaking information. This way every packet can
be encrypted by itself at a lower level, preventing sniffers (program to eavesdrop network traffic) from accessing the
information in the packet.
Multicast and Quality of Service
As streaming audio and video becomes more widely used over the Internet along with other time critical
applications like news and financial information the limitations of IPv4 become more obvious. Version 6 of the
Internet Protocol has a feature called multicast. It allows broadcasters of audio and video streams to send out just
one packet of the same information to many receiptants. It works like a tree, whenever a network is split into a few
smaller ones, the information will be replicated and distributed down the tree. This decreases the network traffic as
audio and video broadcasts are expected to increase heavily as more people get faster Internet connections. Quality
of Service is also important for the future of streaming, by setting a high value of Quality of Service the routers in
the path to the target computer will prioritise the packet thus leading to a faster delivery. The risk with is of course
that all applications like e-mail and news that otherwise would be considered a non-time critical also set a high
Quality of Service to make it get delivered quickly.
One of the major headaches for network administrators of large networks it managing IP addresses. The InterNIC
wants to have as many addresses free as possible for future usage, giving the administrators a lot of work tracking
which addresses that are used and which are free. When IPv6 is used on a network such problems can be disavowed.
The protocol has a sort of autoconfiguration so when a host is connected to a network it will talk to the local router
by using a temporary IP address and the router will tell the host what IP it should use. The router has previously
been defined a range of addresses by the system administrator. In the same way if a network is moved or there is a
change of ISP, resulting in a major IP change, the administrator will reconfigure the router to the new IP range and it
will then, by the Neighbour Discovery (ND) protocol, tell the hosts their new IP‟s.
To support highly dynamic situations in the future IPv6, contains features for IP forwarding. When a user leaves
work to go on a business trip for example he will logout from the local are network. The system will then tell the
local router that all data to that user is to be forwarded to his laptop IP instead of his work IP. Forwarding allows
domain name entries to be unchanged while the user is connected to a network on the other side of the earth.
When or if IPv6 makes it to the common market the transition will not be too hard. The next generation protocol is
created to work with the old version of IP. The first routers that will be installed using the new protocol will also
handle the old version so IPv4 can talk to it during the transition period. The only dependency that exists is the DNS.
When a subnet is upgraded to IPv6, the domain name server must also be updated to handle the new IP addresses.
The network that the subnet is connected to does not have to be upgraded. If an IPv6 host connects to a different
IPv6 host on a different subnet where the data has to travel over an old IPv4 network, it will only get encapsulated
with IPv4 headers. This method is called tunnelling. When the packet once reaches the destination IPv6 network the
IPv4 headers will be removed by the router and the packet will be submitted to the correct IPv6 host. The old
version four network will not know that it ever carried something it actually cannot handle.
Currently there is a virtual world-wide
IPv6 network called 6bone created to
test implementations of IPv6 in a
working environment while not risking
production routers and important
systems. The network operates on top of
the ordinary Internet by tunnelling
discussed earlier. 6bone is not however
a new Internet that we will move to
once IPv6 is ready for commercial use,
instead it is just a playground for
scientist and it will disappear when IPv6
becomes widely used.
New domain names
Not in anyway related to the proposed IPv6 standard, seven new top-level domain names have been proposed as
addition to the current com, org, net and others.
.firm for businesses or firms
.store for selling products
.web for www related sites
.arts for cultural sites
.rec for recreational and entertainment sites
.info for information sites
.nom for personal homepages
It might seem great with all these new categories but will they actually matter? The owners of many domains today
registered them to make profit. By registering corporate or product names they want to sell them to the rightful
owner later on. The same way they can also register good domains like video or cd.store by just being quick to
register and then sell to the highest bidder. To stop domain opportunist large corporations also have to register their
domain at all top level domains just the way they have done with the country domains. Most likely the new domains,
whenever (or if) they arrive will just create a storm of registrations, and all the sought-after domains will be taken
immediately. And along with them there will also be the normal copyright disputes etc that already exist with the
Many new connection forms are emerging as the demand for high speed Internet grows. Users no longer wish to
browse with slow modems. In this section we will look into some of the technologies that might become popular in
The modems most people use to connect to the Internet have a speed of 33.6 kbps (thousand bits per second), this
gives a transfer rate of about 3 kb/sec (thousand bytes per second) on the Internet. When downloading files this is
very slow. The phone lines in general support much higher communication speeds, here are some of them.
Integrated Services Digital Network
ISDN is a speedier version of standard phone lines. The difference lies in the way the connection is handled. Instead
of making calls analogue when sending them to the subscriber at the telephone station, digital technology is used all
the way out over the standard copper cable. Normal phones are analogue, so this system requires an adapter that
converts the signal to the analogue format. ISDN provides two channels of each 64 kbps for voice and data and one
service channel at 16 kbps to handle communication between the telephones and telephone station, like notifying
when there is an incoming call. Recent developments of ISDN allow the use of the service channel for other than
service. Since this channel is used all the time, not only when a phone or the Internet is used, it would allow a
computer connected with ISDN to be online constantly, and when needed it could connect with one of that data lines
to provide higher speed. This addition to the ISDN system is not widely spread but it shows good use of existing
Connections through satellite is starting to become available, the pro‟s of it is the high data transfer speed. Common
users can expect speed ranging from 400 to 800 kbps while professional equipment could increase that speed
dramatically over the 10 Mbps‟. The big con with satellites for consumer usage is that it is a one way system, you
will have to have a modem connection open for communication back to the Internet (to request and acknowledge
information). Another con is the latency, transferring data up to space takes a while, this creates some slight delays
that could for example make gameplay over Internet very tedious.
The DSL family of technologies is just like ISDN and extension of your current phone line. DSL technology
however provides much higher speeds but also requires technical upgrades at the local telephone station. Besides
that you cannot be to far from the telephone station as background noise will disturb the signal, giving you much
slow transfers than the 9 Mbps that ADSL can offer. Digital Subscriber Line, which is its long name, is probably one
of the connection forms that will be popular in the future, as long as you live near the telephone station.
The cables that already are laid out to handle cable TV can carry data very well. Many cable networks are only good
at providing data, users connecting through a cable modem can get speeds of a couple of Mbps from the Internet
while sending might go down to a few hundred kbps. This differs widely depending on the system that the cable
operator is using.
Just as the Internet wasn‟t created to grow like it did, the European mobile phone system, GSM (Global System
Mobile) wasn‟t created to handle data. The system is currently limited to 9.6 kbps, while
normal telephone line modems can get speeds up to 56 kbps. This makes mobile
Internet access very limited, only e-mail messages can be sent and received at a
reasonable speed and browsing www would be very slow. Connection to a
mobile phone is no longer needed, telecommunication companies have
phones with integrated computers as well as PC-Cards with built-in
phones. Fast communication over GSM is not very good yet but by the
year 2001, the GSM systems are expected to be enhanced for data
transfer at 384 kbps.
Universal Mobile Telephone System
On January 29 1998 in Paris at the European Telecommunications
Standards Institute meeting the standard for the third generation of
mobile phones was set. The first generation was analogue, the second
generation had digital phone systems like GSM and AMPS (an
American mobile phone standard). The new system‟s technical
standard is called UTRA while the phone system is called UMTS. It has
some major advantages over older systems. First of all the voice
quality should be comparable to fixed lines, second and most
important in this context is its support for higher data rates. For indoor access speeds up to 2 Mbps can be reached
while wide area access only allows speeds up to 384 kbps. What really shows the aim for global mobile network
communication is the support for multiple simultaneous connections and support for IP packet handling.
There are systems designed specifically for wireless Internet, in Seattle, Washington DC and San Francisco systems
consist of 1000‟s of small transmitters on light poles. The system provides access all over the central area at
ordinary modem speed. The system is very flexible in the sense you can move around freely in the city and it
requires only a small antenna on the special Ricochetmodem. The system currently has more than 15,000 users and
bandwidth upgrades to provide higher data speeds can be expected in the future.
Multichannel Multipoint Distribution System
A system similar to the above is MMDS, it does however require the receiver to have a small dish besides the
modem making it non-mobile. The good part of it however is that it can do speeds up to 30 Mbps. Speeds like that
allow television and video broadcasting. With digital transmitting technology it might also be possible to triple the
speed. The problem with the system is that all the users in the same region share bandwidth, so when everyone
wants to surf the web, it will not be as effective as when sending TV. This system is yet half-mobile since it does not
require any cables to be drawn making it at least portable.
Shared Wireless Access Protocol
Not only are people expected to communicate with each other over the Internet, electronic devices at home will also
be talking to each other in the future. Almost all the major computer companies are working together to develop
SWAP, a protocol that defines how devices talk to each other by radio signals. The system would allow you to
control telephones, lights, alarms, computers and ovens, all across the Internet. Technically one home network can
control 127 devices and communicate at 2 Mbps. It was for these kind of applications the Internet programming
languages Java first of all was created by Sun Microsystems. There are competing standards to both SWAP and Java
however. Microsoft wants the devices to be control by a miniature version of their Windows operating system while
electricity companies want the communication to go not by radio but through the electricity lines. They do have a
good point with this as most of the devices that are planned to be connected to the home network are connected to
with an electric cable. Also the speed of it is currently the same as SWAP, with improvements likely to come.
Internet over electric lines also works for out of the house connections, like browsing and e-mail. The great
advantage of it is that everyone has it and it would only require minor changes to the power system and a small
adapter at home.