unlock network blocked dongles to use any sim card from any operator using linux

Do you have any dongle bought from any operator who blocked the dongle to the particular operator/network?

sinhala translation is available at ලිනක්ස් මගින් ඩොංගල් අන්ලොක් කරමු.

if you are in a hurry and don't like to read the whole article, simply go to the bottom of the article to know how the dongle could be unlocked.

Reasons to network/operator block the dongle from using the SIM cards from other operators.

• To stop using a sim card from another operator who is a competitor of the operator
• to keep the customer with one operator. it will help to earn more money while keeping the customer with the particular operator. 
• customer can't switch to another operator with the network blocked dongle because the dongle doesn't accept the sim card from any new operator than the network blocked operator.

Reasons to unlock the dongle

• to switch to a new operator because the new operator would provide more efficient and economical packages to the customer
• coverage/signal problems to some places of the country. 
• customer service of the operator is unsatisfactory

Be careful

• most of the dongles comes with a warranty for some period of time. that warranty would be avoid if the dongle is unlocked.
• if the dongle is provided at low cost or on an agreement with the operator, it would be violating the agreement with the operator. sometimes some operators provide the dongles with the packages with the agreements. so, unlocking or using another sim card or package form another operator could be illegal. 
• user will have to pay for the dongle if canceling the agreement.

After all you would need to switch to another operator due to any reason and if you had to buy another dongle to be used with the new operator, never buy an another dongle, try to use the old dongle while buying a suitable broadband or 3g plan from the new operator. don't throw out the old network blocked dongle because it would cost your hard earn money and would pollute the environment.

I'm using a linux (openSuse) operating system in my Laptop and I encourage other to use Linux on their computers. My dongle had cost me a sum of LKR 7829.99 on December 2009 (with one year warranty) without any plan or agreement but it has blocked to a mobile network operator from using another sim from other operators. Still I'm satisfied with the network but I needed to unlock the dongle for a fun because I needed to know is it could be done by my own.



Now I would explain how to unlock the network blocked dongle to be used with another operator.

First of all you need to know the IMEI number of your dongle. then you could find the unlock code using a web site in the internet. I used a web site on this url to get the unlock code for my dongle. ( http://www.mapmyplace.com/calc/ )

then I installed "minicom" to unlock the dongle using my laptop.
simply the linux package manager helps to install the "minicom" using the graphical way. but there's the text mode as well.

on ubuntu or debian based systems open the terminal and type
sudo apt-get install minicom

on redhat or fedora based systems (yum installer) open the terminal and type
su yum install minicom

on redhat or fedora based systems (yum installer) open the terminal and type
su zypper install minicom

then we need to find the place which the dongle is mounted. most of the cases ttyUSB0 will be the place which identifies the dongle.
use 

• "tail -f /var/log/syslog" on debian based systems or 
• "tail -f /var/log/messages" on rpm based systems 

as superuser/su to check whether the ttyUSB0 is the port which dongle attached. unplug and plug the dongle after running the command to find the port easily.

open the "terminal"
log in as root/super user using "sudo" (debian/ubuntu) or "su" (rpm) in terminal

type
minicom -s

will open a window like

then select "serial port setup"

type "A" in front of the "Change which setting?" to change the port attached the dongle
change /dev/ttyS1 to the port which your dongle is attached. /dev/ttyUSB0 is for mine

type "E" in front of the "Change which setting?" to change the Bps/Par/Bits

type "C" in front of "Choice, or <enter> to exit. it will select 9600 for current speed.

press "enter" to exit from the menu

then it will show a window like

Press "esc" to go to previous/main menu

select "modem and dialing"

it will initialize the modem. don't worry any message didn't come. then select exit from main menu

then the window will go off and will show command line to unlock the dongle

then type the command to unlock the dongle.



AT^CARDLOCK="12345678"

command should be in capital/uppercase letters and the 12345678 should be replaced with the code you got for the IMEI  of your dongle. unlock code should be within double quotes " and ". then press enter to continue.
it should show a message like "OK" or something if you done properly.

AT^CARDLOCK="12345678"     
OK                                              


you've done.

then insert SIM card (from previously blocked operator) in to the dongle and use it.

thank you Girobiro's blog for the article about "Unlock 3G USB Dongles in Linux" helping me to get an idea how to unlock my dongle.

Why we Forward emails?????

Life is the first gift,
Love is the second,
Understanding is the third.

Sometimes, we think of why friends keep
forwarding mails to us
without writing a single word........
Maybe this could explain why..........

When you have nothing to say,
still want to keep contact,
guess what you do,
you forward mails.

When you have something to say,
but don't know what,
and don't know how,
guess what you do,
you forward mails.

When you have a lot to say,
and don't know why,
guess what you do,
you forward mails.

When you are still wanted,
when you are still remembered,
when you are still important,
when you are still loved,
when you are still missed,
guess what you get
A Forwarded Mail.

So dear friends and family
next time if I forward you a mail
don't think I have only sent you a mail
but I've remembered you in my heart.



references: accessed on 11-oct-11
http://www.prokerala.com/community/showthread.php?t=395
http://my.opera.com/Mayur/blog/show.dml/329545

Design your blogger template by yourself

I found something new when I roaming in the internet. It's http://draft.blogger.com which helps to design more creative blogger templates than before as our wish.
I think if you are a blogger at blogger/blogspot (http://www.blogger.com) you could remember there was a limited number of templates to use inside blogger from the scratch. If we need to use another template, we had to find a good template and had to do many changes to use it under blogger/blogspot.

now blogger/blogspot gives us a new template designer by themselves. Try using http://draft.blogger.com url and crate your own template. If you are in doubt , simply log in to http://www.blogger.com and change "www" with the word "draft".
Then you will see a page saying " make blogger in draft my default Dashboard". It's your choice to decide your default dashboard. You can ignore it..

Then click on the "layout" link of your blog.
You'll see an additional link saying "template designer". Click on it and go to the page. You'll find many valuable features to change/edit your template. If you have done somthing wrong , there is a link to "reset" the edits to default. You could see a preview while you doing changes to the template. (template designer shows the place which we do our changes by highligting them at the "bottom" of the page.

Then click on the "view blog" to see how could you see the blog and click on the "APPLY TO BLOG" if you satisfy with your template.

How to control your privacy in facebook?

Wanna know how to control your privacy when using facebook? read this guide which created by me..
http://www.box.net/shared/aoj17poati
http://www.box.net/shared/aoj17poati

Pros and Cons of the HTML

this is an another post of mine for our LMS-forum...

HTML stands for "Hyper Text Markup Language" and it's widely spread all around the web.

there are many advantages of HTML and I think there aren't too many disadvantages.

Advantages

• We can use HTML mixed with scripting languages like JavaScript.
• HTML is easier to learn (for me)
• HTML could be read using many programs like email clients, web browsers and many.
• Runs on the client side. So, we could view the source using a web-browser.
• Universal, versatile and free to use.
• Supports to multiple platforms. ( doesn't matter if that HTML page was created using a Windows PC or a MAC, that page runs well on Linux as well.)
• Could be read using even a text mode web-browser.
• Easy to read by the Search Engines.
• Many scripting languages like php needed to use HTML. (when creating forms using php we couldn't do it using just php and HTML helps to the scene to make easier the creation of the form)
• No need to install anything in to the client PC although it runs in the client side.
• Lightweight. (html pages are consists from texts and because of that reason the pages are very small in size)so it's easy to upload and download. (in to the server and from the server)

Disadvantages ( I think there aren't too many disadvantages of HTML)

• HTML is far behind than other languages because it's "Static" language.
• Couldn't used for Database connectivity.
• Couldn't create Dynamic pages using just HTML only. need to mix some other scripting languages with it to create dynamic pages.
• Lack of security. But it doesn't matter because other scripting languages help it and never used (HTML only) for any secure web pages.
• need to create several pages when distributing. It means there will be several/many files. (we could distribute as one file for everything when using a programming language)

How networking helps to a bank ...

this is an another post of mine for our LMS forum...

Banking System needs a very good network with its every branch. If not, customers couldn't deposit or withdraw money from everywhere in the island and they will have to go to the branch that they opened their accounts when they needs to deposit or withdraw money. because every branch is connected to each other, customers wouldn't face to any difficult when banking for their needs and they can do their banking needs at any branch in the island. It means , if anyone borrowed any loan from any branch, he or she could pay it using any branch of the bank. If there's a bank without the network, customers never come to that bank to do their banking needs, because if any customer done any banking with any branch, he or she should come to that particular branch to do the rest of their banking. It makes the customer unhappy. Keeping the customer happy and making their works too easy , attracts more customers to the business. Networking helps to ease the management of the bank by a central location. If there is a natural disaster or something occurred and if any branch becomes faulty and out-of-service, customers could use another branch to do their banking needs. So, networking is essential to the banking system in Sri-Lanka.

The future computer in 10 years of time

Here is a article which I have written for a discussion forum of our BIT website.

Question:
 
Imagine that you need to order a computer in 10 years time for your personal use. What type of a computer would you expect to have by then. If you see it different from the current PCs, just indicate why you foresee such a change.


Answer:


I think the computers in 10 years of time will be very different than now. People will think about the protection of their data and availability of data. So, people will prefer to use “on line storage” than storing the files on a Hard disk drive. So, no need to use hard disks with high memory capacity. So, manufacturers will make computers without a hard disk. Most of the time, computer will be having only a “web browser” and all the softwares will be installed in the Internet. (currently google tries to do so and “Chrome-OS” will be play more role on it) Then no need to pay for the operating system and softwares because a flat rate of subscription will provide every software needs. What it means is the Internet will be essential to day to day life. So, ever computer will be having inbuilt “High speed data devices” to access to the Internet.

As a result of people live in a very busy, and communication world, people will use “Laptop” computers than now. It will help them to live their mobile life very easily. Manufacturers will make more powerful laptop computers with low weight to easily carry everywhere. “Nuclear cell” batteries will be provide more accurate electricity/current for a long time.

Now, it's not a fiction a computer without a keyboard because Apple Inc has announced a model of a computer without a keyboard. User could type using an “on-screen keyboard” from the movement of his/her eyes. Then no need to type by hand. Then the computer will only be a Screen. By 10 years time, the computer monitor will be a thin paper which could keep inside the pocket.

Artificial intelligence is the main idea of the 5th generation computers. By 10 years of time people will be able to use computer by Voice. Then no need to type anymore and people who blind could use a computer without any difficulties. People could spend their time by talking with the computer when they are lonely. Computer will be provide advices to the user when needed.

How to use "Huawei e156G HSDPA" on Linux ( tested with openSUSE 11.0 )

Recently I bought a Huawei e156G HSDPA USB stick dongle to use to access to the Internet. After connecting the Huawei e156G in to my PC which is running with openSUSE 11.0 it I didn't know how to use it to access to the Internet.
So, I typed lsusb and found the system identifies the dongle Huawei e156G as "Huawei Technologies Co., Ltd. E220 HSDPA Modem / E270 HSDPA/HSUPA Modem". Then I restarted my PC with Windows XP , plugged my Huawei e156G dongle and searched the internet to know "How to connect Huawei e156G with Linux?".
Normally I don't like to use windows XP in my PC because "I love Linux". But if I need to use my dongle on Linux, I have to get some help from M$ to download the packages. I don't hesitate to get some help from another O/S when I needed.

After few searches I found a link to OpenSuse website to another site.(http://en.opensuse.org/SDB:HUAWEI_E220_Support). Then I downloaded huawei.tar.bz2 from the site http://oozie.fm.interia.pl/pro/huawei-e220/ and decompressed it using the terminal and installed that package to my system.

tar -xjvf huawei.tar.bz2
cd huawei
su
[password] ( [password] = your password for the root )
make install_suse


when the dongle is connected to a USB port , system will identify the USB dongle at /dev/ttyUSB0

then you could edit the wvdial-huawei.conf file which is in the /etc/
( path : /etc/wvdial-huawei.conf )
no need to edit whole file. It's enough to edit Phone , username , password fields to work with some ISPs. check your ISP for phone number which is needed to dial to connect and username , password also.

then you could surf the internet using the wvdial command.

you can try this with different distros and distributions.

Source : " http://en.opensuse.org/SDB:HUAWEI_E220_Support " Accessed on 24-12-2009 "
Technorati Tags: Huawei e156G

හුවාවි e156G ඩොංගලය openSUSE සමග භාවිතා කිරීම.

හුවාවි e156G ඩොංගලය openSUSE සමග භාවිතා කිරීම.

e156G ෙඩාංගලය openSUSE සමග භාවිතා කිරීම ඉතාම පහසු ක්රියාවකි.

මුලින්ම wvdial පිහිටුවා ගත යුතුය. එය පිහිටුවා ගැනීම එතරම් අසීරු ෙනාවන බැවින් ඔබට බාර කරමි.

අනතුරුව ඔබ http://oozie.fm.interia.pl/pro/huawei-e220/ යන ලිපිනයෙන් huawei-e220 සදහා වන huawei.tar.bz2 ගොනුව බාගත කර ගත යුතුය.
( link is from " http://en.opensuse.org/SDB:HUAWEI_E220_Support " Accessed on 24-12-2009 )

අනතුරුව huawei.tar.bz2 හි අඩංගු ගොනු පිහිටුවීම සදහා terminal එක මත පහත දැක්වෙන විධාන සටහන් කරන්න.

tar -xjvf huawei.tar.bz2
cd huawei
su
[password] ( [password] = ඔබ ෙග් root සදහා වන මුර පදය )
make install_suse

අනතුරුව ඩොංගලය USB port එකට සම්බන්ධ කල විට පරිගණකය මගින් /dev/ttyUSB0 එය හදුනා ගනී.

ඉන් පසු /etc හි අැති wvdial-huawei.conf ගොනුව edit කල යුතුය. /etc/wvdial-huawei.conf
එයට ඔබ කැමති text editor එකක් භාවිත කල හැක.

එහි Modem , Phone , username , password යන ස්ථාන වලට අදාල වෙනස්කම් සිදු කරන්න.

[Dialer Defaults]
Modem = /dev/ttyUSB0
Phone = *99#
username =
password =

අනතුරුව wvdial-huawei.conf සුරක්ෂිත කරන්න.

අනතුරුව wvdial විධානය භාවිතා කර අන්තර්ජාලයට සම්බන්ධ වන්න.

Source : " http://en.opensuse.org/SDB:HUAWEI_E220_Support " Accessed on 24-12-2009 "

who is “hacker” and who is “cracker” ?

Sinhala unicode version of this article also available.

hacker is a famous word in the computer field. Cracker also a famous word but not as famous as the word hacker.

Before we see about hacker, we'll see about the cracker. Cracker is a well knowledgeable programmer who develops programs to computers. Every time he is a good person and there isn't any harm to a computer from him. But many people misidentify him as a hacker. The truth is Cracker isn't a hacker and he never hack a computer.

Now it's time to see about hacker.

There are three types of hackers “White hat hacker” , “Black hat hacker” and “Grey hat hacker”.

“White hat hacker” is the person who cares about the “security of the computer system”. He always try to find errors in the system and solve the problems to prove the security. Most companies hire them to check the security vulnerabilities in their networks and computer systems. They never do any illegal work which harmful to the system , to data or people.

“Black hat hacker” is the worst person who enters tries to steal something from any computer or network. He is a bads person. He is a threat to data, privacy and computer systems. They use the data which they got by hacking to earn money. They know which they do is illegal. Because of their illegal work, they always caught to the “law” and “be in the jail” for many times.

“Grey hat hacker” also a person who is very knowledgeable and try to improve the security of the system. But when he thought or got the chance he do what “Black hat hacker” does. So, “Grey hat hacker” is the person who is in between “White hat hacker” and “Black hat hacker”. Because of their illegal work, they also caught to the “law” and “be in the jail” for many times.

---

We are in a Global village, which connected by communication. So, data is valuable to every one. Many people like to learn how to hack because it helps them to secure them from hackers. So, they think to become a “White hat hacker” and learns how to hack. After learning some techniques, they forget about their aim which was to become a “White hat hacker” and try to hack and to be a threat to computers and networks. Sometimes they do it for Fun and sometimes to earn money. But these days, the law is strict for Cyber-crimes. So, think twice before hack.

හැකර් කියන්නේ කාටද ? එතකොට කවුද ක්රැකර් කියන්නේ ?

හැකර් කියන්නේ කාටද ? එතකොට කවුද ක්රැකර් කියන්නේ ?

typed using sinhala unicode.

English translation of this article will be available as soon as possible.

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හැකර් කියන වචනය පරිගණක ලෝකයේදී නිතරම අහන්න ලැබෙන වචනයක් වගේම හරිම ප්‍රසිද්ධ වචනයක්.

හැකර් තරමින් ප්‍රසිද්ධ නැතත් ක්රැකර් කියන වචනයත් යම් තරමකට ප්‍රසිද්ධයි. නමුත් හැකර් හා ක්රැකර් යන වචන දෙක භාවිතා කරන ආකාරය තවමත් හරිම පැටලිලි සහිතයි. සමහරු කියන්නේ ක්රැකර් කියන්නේ පරිගණක පිළිබද විශාරදයෙක් , එයා පරිගණක වලට වැඩසටහන් සකසන්නෙක් , එයාගෙන් කාටවත් හානියක් නෑ කියලයි. ඒත් සමහරු ක්රැක් කියන වචනය නිසා හිතාගෙන ඉන්නේ ක්රැකර් කියන්නේත් හැකර්ට කියලයි. ඒත් දැනට පිළිගත හැකි මූලාශ්‍ර වලින් කියැවෙන්නේ නම් ක්රැකර් ගෙන් කාටවත් හානියක් නෑ කියලයි.

දැන් ඉතින් ක්රැකර් අමතක කරලා හැකර් ගැන හොයලා බලමු.

හැකර්ලා වර්ග තුනක් ඉන්නවා.

පලමු කාණ්ඩය තමයි "වයිට් හැට් හැකර්". එහෙම නැත්තම් "එතිකල් හැකර්".

මේ අය පරිගණක ආරක්ෂාව පිළිබද විශාරදයින්. ඔවුන්ගෙන් කාටවත් හානියක් නෑ. මේ අය නිතරම පරිගණක පද්ධති වල ආරක්ෂාව පිළිබදව පරීක්ෂණ කරලා, පද්ධති වල ආරක්ෂාව තහවුරු කරනවා. ඒ නිසාම මේ අයව සමහර සමාගම් තමන් ගේ පරිගණක පද්ධති වල ආරක්ෂාව පිළිබදව තහවුරු කර ගැනීමට යොදා ගන්නවා.

දෙවෙනි කාණ්ඩය තමයි "බ්ලැක් හැට් හැකර්".

මේ අය පරිගණක ආරක්ෂාවට තර්ජනයක්. නිතරම බලන්නේ ‍‍වෙන කෙනෙක් ගේ පරිගණක‍යකට රිංගලා ‍මොනවා හරි හොරකම් කරන්නමයි. පරිගණක පද්ධතියකට එහෙම ඇතුල් වුනොත් සොරි තමයි ඉතින්. මෙයාලා කරන්නේ වැරැද්දක් කියලා මෙයාලා දන්න‍වා. මෙයාලා කරන වැඩ නිසා නිතරම නඩු-හබ වලට පැටලෙනවා.

තුන්වෙනි කාණ්ඩය තමයි "‍ග්‍රේ හැට් හැකර්".

මෙයාලාත් පරිගණක ආරක්ෂාව පිළිබද විශාරදයින්. ඒත් "වයිට් හැට් හැකර් " කරන හොද වැඩ ව‍ගේම හිතුනොත්/අවස්ථාව ලැබුනොත් "බ්ලැක් හැට් හැකර්" කරන නරක වැඩත් මෙයාලා කරනවා. ඒ නිසා මෙයාලාත් නඩු-හබ වලට පැටලෙනවා.

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ගොඩක් අය හැක් කරන හැටි ඉගෙන ගන්න හරිම ආසයි. ඒකට උත්සාහත් කරනවා. මොනවා වුනත් හැක් කරන හැටි දන්න‍වා නම් හැකර්ලාගෙන් බේරෙන එකත් ලේසියි. ඒ පරමාර්ථයෙන් හැක් කරන හැටි ඉගෙන ගන්න ‍ගොඩක් අය ටික කාලෙකදි තමන්ගේ අරමුණ අමතක කරලා "බ්ලැක් හැට් හැකර්" කෙනෙක් වෙන‍වා. ඒ වගේ අයට දැන් ගොඩක් තෑගි දෙනවාලු "උසාවිය පැත්තේ එන්න කියලා". සම‍හරුන්ට "ආණ්ඩුවේ බෝඩිමේ නවතින්නත් ‍දෙනවාලු" (ආණ්ඩුවේ බෝඩිමේ කෑම බීම නිකන් ලු ).

hit counter on my blog

i started to blog last year, and i have been blogged for one year. i thought i'm the only1who read my blog till yesterday. so, i added a hit counter to check it. after adding a hit counter to my blog, i found visitors from 5countries, 4web browsers and 3operating systems with 8 unique visits within 12 hours.
i would like to thank you for your visit and i hope to add some valuble posts as i get time to post.
thanks in advance. keep looking.

Broadband technologies

Broadband Internet access, which widely called broadband is more faster and reliable than Dial-Up internet access.

There isn't a registered or accurate explenation for Broadband, the speed ranging up from 64 kbit/s up to 8 Mbit/s and more. the 2006 OECD report is typical by defining broadband as having download data transfer rates equal to or faster than 256 kbit/s, while the United States (US) Federal Communications Commission (FCC) as of 2009, defines "Basic Broadband" as data transmission speeds exceeding 768 kilobits per second (Kbps).

Data rates are defined in terms of maximum download because several common consumer broadband technologies such as ADSL are "asymmetric"—supporting much slower maximum upload data rate than download.

"Broadband penetration" is now treated as a key economic indicator.

Although ISPs advertised about their bandwidth, customer/user can't get the actual bandwidth which ISP tells because of the overselling the bandwidth and the quality of the equipments.

Broadband technologies :

• Mainly consists of DSL and Cable modems.

• In some areas where DSL or Cable modems didn't available, there are wireless internet connecting options like Wi-Fi, HSDPA, EV-D0 and WiMax.

DSL ( Digital subscriber line )

Digital subscriber line, or DSL, is more expensive than dialup, but provides a faster

connection. DSL also uses telephone lines, but unlike dialup access, DSL provides a

continuous connection to the Internet. This connection option uses a special high-speed

modem that separates the DSL signal from the telephone signal and provides an Ethernet

connection to a host computer or LAN.

Digital Subscriber Line (DSL) technology is a modem technology that uses existing twisted-pair telephone lines to transport high-bandwidth data.

xDSL technologies

• ADSL

• SDSL

• HDSL

• HDSL-2

• G.SHDL

• IDSL

• VDSL

xDSL is drawing significant attention from implementers and service providers because it promises to deliver high-bandwidth data rates to dispersed locations with relatively small changes to the existing telco infrastructure.

xDSL services are

• dedicated

• point-to-point

public network access over twisted-pair copper wire on the local loop (last mile) between a network service provider's (NSP) central office and the customer site, or on local loops created either intrabuilding or intracampus.

ADSL-Asymmetric Digital Subscriber Line

Allows more bandwidth downstream—from an NSP's central office to the customer site—than upstream from the subscriber to the central office. This asymmetry, combined with always-on access (which eliminates call setup)

Advantages:

• Could use phone line and ADSL line at the same time

• Could use to view videos, listen to songs, download files and for many purpose.

• More than 6Mbps bandwidth available.

• Continuous connection / Stable

• can be purchased with various speed ranges and capabilities

• Bandwidth is unlimited in some countries

• can use existing phone line

Disadvantages:

• Limited to 4Km radius from the nearest telephone exchange.

• Have to buy a ADSL modem or router.

• Expensive in some countries.

• Not available in some areas

• receiving data is faster than sending data

An ADSL circuit connects an ADSL modem on each end of a twisted-pair telephone line, creating three information channels:

• a high-speed downstream channel

• a medium-speed duplex channel

• a basic telephone service channel

ADSL modems accommodate Asynchronous Transfer Mode (ATM) transport with variable rates and compensation for ATM overhead, as well as IP protocols.

ADSL uses two pieces of equipment, one on the customer end and one at the Internet service provider, telephone company or other provider of DSL services. At the customer's location there is a DSL transceiver, which may also provide other services. The DSL service provider has a DSL Access Multiplexer (DSLAM) to receive customer connections.

The DSLAM at the access provider is the equipment that really allows DSL to happen.

SDSL Symmetric Digital Subscriber Line (SDSL) allows equal bandwidth downstream from an NSP's central office to the customer site as upstream from the subscriber to the central office. SDSL supports data only on a single line and does not support analog calls. The symmetry that SDSL offers, combined with always-on access (which eliminates call setup) Because traffic is symmetrical, file transfer, web hosting, and distance-learning applications can effectively be implemented with SDSL. HDSL Originally developed by Bellcore, high bit-rate DSL (HDSL)/T1/E1 technologies have been standardized by ANSI (two-pair T1 transmission, with a data rate of 784 kbps on each twisted pair ) in the United States and by ETSI ( two-pair E1 system, with each pair carrying 1168 kbps, and a three-pair E1 system, with 784 kbps on each twisted pair ) in Europe. T1 service can be installed by installing HDSL modems at each end of the line. HDSL is heavily used in cellular telephone buildouts. HDSL does have drawbacks. First, no provision exists for analog voice because it uses the voice band. Second, ADSL achieves better speeds than HDSL because ADSL's asymmetry deliberately keeps the crosstalk at one end of the line. Symmetric systems such as HDSL have crosstalk at both ends. HDSL-2 HDSL-2 is an emerging standard and a promising alternative to HDSL. The intention is to offer a symmetric service at T1 speeds using a single-wire pair rather than two pairs. The biggest advantage of HDSL-2, which was developed to serve as a standard by which different vendors' equipment could interoperate, is that it is designed not to interfere with other services. However, HDSL-2 is full rate only, offering services only at 1.5 Mbps. ISDN Digital Subscriber Line is a cross between ISDN and xDSL Unlike ISDN, ISDL does not connect through the voice switch. A new piece of data communications equipment terminates the ISDL connection and shuts it off to a router or data switch. This is a key feature because the overloading of central office voice switches by data users is a growing problem for telcos. The limitation of ISDL is that the customer no longer has access to ISDN signaling or voice services. But for Internet service providers, who do not provide a public voice service, ISDL is an interesting way of using POTS dial service to offer higher-speed Internet access, targeting the embedded base of more than five million ISDN users as an initial market. VDSL transmits high-speed data over short reaches of twisted-pair copper telephone lines, with a range of speeds depending on actual line length. The maximum downstream rate under consideration 51 and 55 Mbps over lines up to 1000 feet (300 m) in length. 13 Mbps over lengths beyond 4000 feet (1500 m) are also common.

ISDN ( Integrated Service Digital Network )

Integrated Service Digital Network (ISDN) is one of the oldest broadband digital access method which is a telephone data service standard.

A basic rate ISDN line is an ISDN line with 2 data "bearer" channels (DS0 - 64 kbit/s each). Using the ISDN bonding technology, we can get 256 kbps or more bandwidth.

Advantages :

• Constant data rate at 64 kbit/s for each DS0 channel.

• Two way broadband symmetric data transmission, unlike ADSL.

• One of the data channels can be used for phone conversation without disturbing the data transmission through the other data channel.

• Call setup is very quick.

• Low latency

• ISDN Voice clarity is unmatched by other phone services.

• Caller ID is available.

• Maximum distance from the central office is much greater than it is for DSL.

• When using ISDN-BRI, there is the possibility of using the low-bandwidth 16 kbit/s "D" channel for packet data and for always on capabilities.

Disadvantages

• ISDN offerings are dwindling in the marketplace due to the widespread use of faster and cheaper alternatives.

• ISDN routers, terminal adapters ("modems"), and telephones are more expensive than ordinary POTS equipment, like dial-up modems.

• ISDN provisioning can be complicated due to the great number of options available.

• ISDN users must dial in to a provider that offers ISDN Internet service, which means that the call could be disconnected.

• ISDN is billed as a phone line, to which is added the bill for Internet ISDN access.

• "Always on" data connections are not available in all locations.

• Some telephone companies charge unusual fees for ISDN, including call setup fees, per minute fees, and higher rates than normal for other services.

Satellite Internet

Is the most expensive way to use the Internet. But availability and bandwidth is greater than other technologies because Satellites can cover any place on the earth by using 3 separate satellites.

Advantages:

• True global broadband Internet access availability

• Mobile connection to the Internet

• High bandwidth

Disadvantages:

• High latency compared to other broadband services, especially 2-way satellite service

• Unreliable: drop-outs are common during travel, inclement weather, and during sunspot activity .

• The narrow-beam highly directional antenna must be accurately pointed to the satellite orbiting overhead

• One-way satellite service requires a data uplink connection .

• Satellite dishes are very large.

Cellular broadband / Wireless Internet

• Cellular phone towers are very widespread, and as cellular networks move to third generation (3G) networks they can support fast data; using technologies such as EVDO, HSDPA and UMTS. These can give broadband access to the Internet, with a cell phone, with Cardbus, ExpressCard, or USB cellular modems, or with cellular broadband routers, which allow more than one computer to be connected to the Internet using one cellular connection.

• Wi-fi and WiMax technology which provides mobility and connectivity as well as the more bandwidth than Dial-Up.

3G technology

• A technology which used for mobile telephony, data, video, voice

• speed differs from 384 kbps to 14.4 Mbps for downlink and till 5.8 Mbps for uplink.

HSDPA ( High-Speed Downlink Packet Access )

• is a 3G technology

• Downlink available from 1.8 Mbps , 3.6 Mbps, 7.2 Mbps and 14.4 Mbps.

• Uplink till 5.8 Mbps

WiMax ( Worldwide Interoperability for Microwave Access )

• a telecommunications technology that provides wireless transmission of data using a variety of transmission modes, from point- to-multipoint links to portable and fully mobile internet access

• Provides speed up to 72 Mbps.

• Based on IEEE 802.16 standard.

uses:

• Connecting Wi-Fi hotspots to the Internet.

• Providing a wireless alternative to cable and DSL for "last mile" broadband access.

• Providing data and telecommunications services.

• Providing a source of Internet connectivity as part of a business continuity plan.

• Providing portable connectivity.

Wi-Fi

• transmit at frequencies of 2.4 GHz or 5 GHz.The higher frequency allows the signal to carry more data.

• use 802.11 networking standards, which come in several flavors (802.11a, 802.11b , 802.11g, 802.11n

• allows local area networks (LANs) to be deployed without wires for client devices

• High mobility

• Security problems occurs

Advantages of wireless technologies:

• more bandwidth than Dial-Up.

• Mobility.

• Availability.

• Could use for media steaming, VoIP and many.

• Easy to connect

• Speed.

Disadvantages of wireless technologies:

• Due to the 3G technology is a shared bandwidth service , bandwidth available from one tower could be shared among many users. So, it'll be slower than usual at sometimes.

• Some service provider's shares single IP address among many users. So, it could make some problems with identity.

• Service fees could be high.

• Limited data bundle will be available to use. ( most service provider's don't provide unlimited data bundles )

• Sometimes , it will have some issues with 3G connectivity although there is a tower nearby.

• Security problems occurs because it hasn't security features by default.

• Due to the radio signals, health problems could occur.

Now it's time to compare Dial-Up internet access with Broadband Internet access.

Differences between Dial-Up internet access and Broadband Internet access.

• In Dialup we can use normal PSTN phone line to access to the Internet if there is a modem available. But we can't use normal PSTN phone line with a Modem or Router without configuring the telephone line for ADSL broadband.

• Dial-Up internet technology is a lower speed with lower bandwidth and Broadband is not like that.

• Dial-Up is suitable for light usage and broadband is suitable for heavy usage.

• Dialup is a low cost method to access the Internet than broadband.

• Dialup charges for Internet usage and for the time we used to surf the web because it make a call to connect to the Intenet and in Broadband it charges flat rate for a data bundle or for the time.

• We can't make calls using the phone while browsing, but we can answer to the calls while browsing with broadband technologies.

• Dialup can't use for VoIP and media streaming but broadband can.

• When we use Dial-Up , there is a possibility to drop the connection more than Broadband.

• Dial-Up can't used for mobile workers if there isn't a PSTN line. But some broadband technologies provide mobility.

Posted by K. W. Roshan Herath [ roshan herath ]

Source:

Broadband technologies

• Broadband Internet Access

  http://en.wikipedia.org/wiki/Broadband

http://en.wikipedia.org/wiki/Category:Broadband

accessed on 08^th September, 2009

Digital Subscriber Line

• http://www.cisco.com/en/US/docs/internetworking/technology/handbook/DSL_Dig_Subscr_Ln.html

accessed on 08^th September, 2009

• http://computer.howstuffworks.com/dsl.htm

accessed on 08^th September, 2009

Wireless technology

• http://en.wikipedia.org/wiki/3G

• http://en.wikipedia.org/wiki/High-Speed_Downlink_Packet_Access

• http://en.wikipedia.org/wiki/WiMAX

• http://communication.howstuffworks.com/mobile-broadband-service.htm

• http://computer.howstuffworks.com/wireless-network.htm

• http://en.wikipedia.org/wiki/Wi-Fi

• http://www.wi-fi.org/

Internet connectivity mechanisms

Internet connectivity mechanisms

Now anybody can access the Internet and get it's benefit. There are several ways to connect to the Internet.

Dial-UP

ISDN

DSL

Cable connections

Wireless connections

T-1, T-2 and T-3 lines

Satellite

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Dial-UP

• Dialup is simply the application of the Public Switched Telephone Network (PSTN) to carry data on behalf of the end user. It involves a customer premises equipment (CPE) device sending the telephone switch a phone number to direct a connection to.

• Speed ranges from 2400 bps to 56 Kbps

• Twisted pair (regular phone lines) is the physical medium.

• Cheap but slow compared with other technologies.

• Speed may degrade due to the amount of line noise

ISDN

• Integrated Services Digital Network is a telephone system network. ISDN is integrates speech and data on the same lines, adding features that were not available in the classic telephone system. access interfaces

  • Basic Rate Interface (BRI)

  • Primary Rate Interface (PRI)

  • Broadband-ISDN (B-ISDN)

• Dedicated telephone line and router required.

• Speed ranges from 64 Kbps to 128 Kbps.

• Physical medium is Twisted pair.

• Not available everywhere but becoming more widespread.

• An ISDN line costs slightly more than a regular telephone line, but you get 2 phone lines from it.

• 56K ISDN is much faster than a 56K dialup line

Digital subscriber line ( DSL )

• Digital subscriber line ( DSL ) is more expensive than dialup, but provides a faster connection. DSL also uses telephone lines, but unlike dialup access, DSL provides a continuous connection to the Internet.

• This connection option uses a special high-speed modem that separates the DSL signal from the telephone signal and provides an Ethernet connection to a host computer or LAN.

• Doesn’t interfere with normal telephone use.

• Bandwidth is dedicated, not shared as with cable.

• Bandwidth is affected by the distance from the network hubs. Must be within 5 km (3.1 miles) of telephone company switch.

• Limited availability.

• Not networkable

Cable Internet

• A cable Internet is a connection option offered by cable television service providers. The Internet signal is carried on the same coaxial cable that delivers cable television to homes and businesses.

• A special cable modem separates the Internet signal from the other signals carried on the cable and provides an Ethernet connection to a host computer or LAN.

• CMTS is the equipments provides the Cable Internet service to the users. It provides the same service which DSLAM offers.

• 512 Kbps to 20 Mbps

• Coaxial cable and in some cases telephone lines used for upstream requests as physical medium

Wireless

• Access is gained by connection to a high speed cellular like local multi-point communications system (LMCS) network via wireless transmitter/receiver.

• Speed is 30 Mbps or more

• Physical medium is Airwaves (antenna)

• Can be used for high speed data, broadcast TV and wireless telephone service.

Satellite

• Satellite connection is an option offered by satellite service providers.

• The user's computer connects through Ethernet to a satellite modem that transmits radio signals to the nearest Point of Presence, or POP, within the satellite network.

• Newer versions have two-way satellite access, removing need for phone line.

• In older versions, the computer sends request for information to an ISP via normal phone dial-up communications and data is returned via high speed satellite to rooftop dish, which relays it to the computer via a decoder box.

• Speed is 30 Mbps or more

• Physical medium is Airwaves (antenna)

• Bandwidth is not shared.

• Satellite companies are set to join the fray soon which could lead to integrated TV and Internet service using the same equipment and WebTV like integrated services

• Latency is typically high

• Some connections require an existing Internet service account.

Frame Relay

• Provides a type of "party line" connection to the Internet.

• Requires a FRAD (Frame Relay Access Device) similar to a modem, or a DSU/CSU.

• speed ranges from 56 Kbps to 1.544 Mbps (or more, depending on connection type)

• Various physical mediums used

• May cost less than ISDN in some locations.

• Limited availability.

• Uses one of the connection types below, fractional up to OC3

Fractional T1 (Flexible DS1)

• Only a portion of the 23 channels available in a T1 line is actually used.

• Speed ranges from 64 Kbps to 1.544 Mbps

• Physical medium is Twisted-pair or coaxial cable

• Cheaper than a full T1 line with growth options of 56 Kbps or 64 Kbps increments as required.

T1

• Special lines and equipment (DSU/CSU and router) required.

• Speed 1.544 Mbps

• Physical medium is Twisted-pair, coaxial cable, or optical fiber

• Typically used for high bandwidth demands such as videoconferencing and heavy graphic file transfers.

• Minimum for large businesses and ISPs.

• Expensive

T3

• Typically used for ISP to Internet infrastructure.

• Speed 44.736 Mbps

• Physical medium is Optical fiber

OC-1

• Typically used for ISP to Internet infrastructure within Internet infrastructure.

• Speed 51.84 Mbps

• Physical medium is Optical fiber

OC-3

• Typically used for large company backbone or Internet backbone.

• Speed 155.52 Mbps

• Physical medium is Optical fiber

The history of the Internet in brief

Here is the brief history of the Internet:



ARPA (1957)

There is a competition between USSR and USA for technology and USSR won it by launching Sputnik. Then USA launched the Advanced Research Projects Agency (ARPA) under the auspices the Department of Defense. Launching the ARPA is mainly focused to maintain a technological lead, particularly with regards to the military.



Packet Switching (1968)

USA wanted to expand the ARPA project to make it reliable at any time. Then the invented packet switching. National Physical Laboratory created the first packet switching network in 1968.



ARPANET (1969)

ARPA created ARPANET in 1969 to help ARPA-funded researchers collaborate more effectively for non profit uses like education and researches which were based on the packet switching technology built at the Rand Corporation in the early 1960s. The first ARPANET were positioned at UCLA, Stanford Research Institute, University of California at Santa Barbara, and University of Utah in Salt Lake City.



TCP/IP (1983)

Between 1969 and 1983, a variety of individual networks sprouted and grew. (BITNET,CSNET). Connecting each of these independent networks was difficult, though, because they didn't use the same protocols and therefore couldn't exchange information.

As a result, ARPA commissioned the development of a new protocol called Transmission Control Protocol/Internet Protocol (TCP/IP) that would allow different networks to connect.

Most networks had changed to TCP/IP in the late 1970s, but ARPANET didn't make the change until January 1, 1983. Thus, many folks consider that date as the birthday of the Internet.


NSF Creates NSFNET (1986)

In 1986 the National Science Foundation created NSFNET, an Internet backbone with a speed of 56K. This backbone connected five super-computing centers located at Princeton, Pittsburgh, UCSD, UIUC, and Cornell. NSFNET precipitated a large number of connections from various universities.

NSFNET has been updated continually since 1986. In 1988, two years after going online, the backbone was upgraded to T1 (1.544M). In 1991, it was upgraded to T3 (44.736M)

ARPANET Is Dismantled (1990)

Newer networks connected the sites that ARPANET connected, and thus ARPANET was no longer useful.

The World Wide Web (1992)

Tim Berners-Lee, a physicist at CERN in Switzerland, invented the World Wide Web (Web) in 1992 as a way to organize information in a more brain-like fashion. His idea was to allow people to make multiple free associations with different bits of information.



NSF Establishes InterNIC (1993)

NSF created InterNIC, a group of businesses that provide a variety of essential services to the Internet.

The Internet Today

The growth of the Internet has been explosive. In 1985, there were about 2,000 host computers on the Internet. Now there are millions of host computers and many more millions of actual users. Now Internet isn't limited to educational and research purpose but also in too many fields like commercial and welfare services and etc.

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posted by roshan herath ( roshan herath )

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- roshan herath

What is called Custom-Subnet-Mask ?

What is called Custom-Subnet-Mask ?

කස්ටම් සබ්නෙටි මාස්ක් යනු කුමක්ද ?

IP Addressපන්ති / classes in IP Addresses



127.0.0.0 ජාලය localhost / loopback ලිපින සදහා වෙන්කර ඇත.

127.0.0.0 network reserved for localhost /loopback addresses.


private address space / පුද්ගලික හෙවත් අභයන්තර ජාල සදහා වෙන්කර ඇති ලිපින


අපට IP Address ම‌ගින් ද පන්තියට පොදු සබ්නෙටි මාස්ක් එය අදාල ජාල පන්තිය හදුනා ගත හැක

නමුත් පරිගණකය එම ආකාර දෙකම භාවිතා කරමින් IP Address එක අදාල ජාල පන්තිය හදුනා ගැනීම සදහා AND යන බූලියානු ගණිත සමීකරණයට ආදේශ කිරීම සිදු කරයි


People could identify the Class that IP Address belongs to by octets of the IP Address and as well as by the Subnet mask.


For your computer to determine the network and subnet portion of an IP address it must “AND” the IP address with the subnet mask.

AND බූලියානු ගණිත සමීකරණය / ANDING Equations

1 AND 1 = 1

1 AND 0 = 0

0 AND 1 = 0

0 AND 0 = 0





ANDබූලියානු ගණිත සමීකරණය භාවිතා කර Custom සබ්නෙටි මාස්ක් සෑදීම.

Making custom subnet-masks using ANDING Equations.


අප ජාල 16 කට බෙදා ඇති 192.168.10.0 යන ජාලය උදාහරණලෙස ලෙස සැලකූ විට ඇතුලත ජාලයෙහි /localnetwork එකෙහි පරිගණක හා ඇතුලත ජාලයට අදාල ජාලගතකිරීමේ උපකරණ මගින් එම උප ජාල හදුනාගත්තද ජාලයෙන් පිටත එනම් අන්තර්ජාලයේ (internet/www) පරිගණක හා ජාලගතකිරීමේ උපකරණ මගින් හදුනාගනුයේ 192.168.10.0 ජාලය පමණි.


ඇතුලත ජාලය උප ජාල වලට බෙදිම සදහා custom සබ්නෙටි මාස්ක් යොදා ගත හැක. මේ සදහා සබ්නෙටි මාස්ක් එකෙහි Networkකොටසට host කොටසින් bits කිපයක් ලබා ගනි. පරිගණකය IP Address එක අදාල පන්තිය හදුනා ගැනිමට AND යන බූලියානු ගණිත සමීකරණයට ආදේශ කිරීම සිදු කරයි.


When you take a single network such as 192.100.10.0 and divide it into 16 smaller networks ,the outside world still sees the network as 192.100.10.0, but the internal computers and routers see 16 smaller subnetworks. Each independent of the other. This can only be accomplished by using a custom subnet mask. A custom subnet mask borrows bits from the host portion of the address to create a subnetwork address between the network and host portions of an IP address. In this example each range has 14 usable addresses in it. The computer must still AND the IP address against the custom subnet mask to see what the network portion is and which subnetwork it belongs to.

192.168.10.0 යන ජාලය උදාහරණලෙස ලෙස සැලකූ විට එක් උප ජාලයක පරිගණක 14 ක් සදහා IP Address ලැබී ඇත.

In this example (192.168.10.0) each range has 14 usable addresses in it.



උප ජාල ගණන හා එක් උප ජාලයකට යෙදිය හැකි පරිගණක ගණන සොයාගන්නේ කෙසේද ?

How to determine the number of subnets and the number of hosts per subnet ?



උදාහරණලෙස bits 4 ක් ජාල / network කොටසට ගත්තේ නම් සෑදෙන උප ජාල ගණන 2 හි 4 වන හි ගුණාකාරය හෙවත් 2x2x2x2=16 කි.

මෙවිට host කොටසේ ඉතිරිව ඇති bit ගණන 8-4=4 කි. එනම් එක් උප ජාලයකට යෙදිය හැකි පරිගණක ගණන 2 හි 4 වන ගුණාකාරය හෙවත් 2x2x2x2=16 කි.


Both formulas calculate the number of hosts or subnets based on the number of binary bits

used. For example if you borrow three bits from the host portion of the address use the

number of subnets formula to determine the total number of subnets gained by borrowing the

three bits. This would be 2 x 2 x 2 x 2 = 16 subnets .


To determine the number of hosts per subnet you would take the number of binary bits used in

the host portion and apply this to the number of hosts per subnet formula If five bits are in the

host portion of the address this would be 2 x 2 x 2 x 2 x 2 = 32 hosts.


නමුත් මතක තබාගතයුතු කරුණක් වන්නේ මෙහිදී සෑදෙන උප ජාල ගණන හා එක් උප ජාලයකට යෙදිය හැකි පරිගණක ගණන සම්පූර්ණයෙන්ම ඒ සදහා යොදාගත නොහැකි බවයි.


ඒ සෑදෙන පළමු උප ජාලය එනම් 192.168.10.0 න් ආරම්භ වී 192.168.10.15 න් අවසන් වන ජාලය ද 192.168.10.240 න් ආරම්භ වී 192.168.10.255 න් අවසන් වන ජාලය ද පරිගණක සදහා යොදාගත නොහැක. ඊට හේතුව කුමක්දැයි තේරුමි ගැනීමට 192.168.10.0 හා 192.168.10.255 යන අගයන් දෙක පමණක් සෑහේ.


192.168.10.0 යනු සම්පූර්ණ ජාලයටම අදාල ජාල ලිපිනයයි (Network Address). 192.168.10.255 යනු සම්පූර්ණ ජාලයටම අදාල විකාශණ (broadcast) ලිපිනයයි. මේ ආකාරයටම සෑම උපජාලයකම ආරම්භක ලිපිනයද අවසාන ලිපිනයද එම උප ජාලයට අදාලව පිළිෙවලින් ජාල ලිපිනය (Network Address) හා ජාලයටම අදාල විකාශණ (broadcast) ලිපිනය වේ.


මේ නිසා යොදාගත හැකි උප ජාල ගණනද එම උප ජාලලෙස සදහා යොදාගත හැකි පරිගණක ගණනද සෑමවිටම ගණනයෙන් ලැබෙන අගයට වඩා 2කින් අඩු අගයකි.


එනම් මෙම 192.168.10.0. ලිපිනයට අදාලව සෑදෙන උප ජාල ගණන 16 වුවද ඉන් උපජාල සදහා යොදාගත හැක්කේ උපජාල 14 කි. ඒ ආකාරයටම සෑදෙන උප ජාලයක භාවිතකල හැකි පරිගණක ගණන 14ක් වේ.


When dealing with the number of hosts per subnet you have to subtract two addresses from

the range. The first address in every range is the subnet number. The last address in every

range is the broadcast address. These two addresses cannot be assigned to any device in

the network which is why you have to subtract two addresses to find the number of usable

addresses in each range.


In some instances the first and last subnet range of addresses are reserved. This is similar to

the first and last host addresses in each range of addreses.


The first range of addresses is the zero subnet. The subnet number for the zero subnet is

also the subnet number for the classful subnet address.


The last range of addresses is the broadcast subnet. The broadcast address for the last

subnet in the broadcast subnet is the same as the classful broadcast address.



මෙහිදී යොදාගෙන අෑති 192.168.10.0 යන ලිපිනයට අදාල ගණනයකිරිම් උදාහරණ ලෙස පමණක් යොදාගත් බව සලකන්න.


අයිතිය (copyright reserved to) / උපුටාගැනීම‌ - IP Addressing and Sub netting workbook ( Student version ) 2.0



created by Roshan Herath using OpenOffice.Org 3.0 on AMD AthlonXP system running by openSUSE Linux 11.0

shared bandwith service - GPRS

GPRS is a shared bandwith service offered by mobile service providers and they charge us for data that we downloaded and uploaded. service providers share the same line(ip address) to provide data access. so, they charge more than for data that used by me, when network got busy. i think they shares same ip as well as the data usage with others and thats why they charge for unused data from me.
i cant imagine another reason.

cisco srilanka

http://vtasl-cisco.com