04-10-2012, 11:24 AM
SEMINOR ON CELLPHONES BEYOND CALL AND SMSs
CELLPHONES.DOC (Size: 237.5 KB / Downloads: 27)
INTRODUCTION
It was in 1973 that Martin Cooper, the then director of research and development in Motorola, beat BellLabs (an arm of AT&t) in the race of inventing a device capable of portable wireless communication. Ninety-seven years ater Graham Bell became the first person to speak on a telephone line, Cooper hauled a hefty and clumsy 2-pound box of circuitry, wires and batteries, while walking down a street in Manhattan and made the first ever private cellular phone call.
We have definitely come a long way since that first 2-pound cellphone.
Cellphones are now sleek gizmos, much more than just wireless phones-they are a utility
An extension of your office, a fashion statement and virtually an indispensable extension of the body!.
In this story, we will introduce you to functions of your cellphone beyond just making and receiving calls and sending SMSs. We will talk of how you can manage your calls and secure your cellphone. SMS is the buzzword, which has gone beyond plainone-to-one text messaging; we’ll lok at the new SMS- based services that cellular operators provide. For the techno-savy, we have insiders on the technology that goes behind cellular networks. And, for you geeks out there, who want something more, we have a list of some ‘common’ cellphone codes. And, of course, even cellular technology uses quite a bit of IT, so we have added that perspective as well.
SHORT AND SWEETY MESSAGES
SMS, the happening thing in communication today, is now not just a service of sending simple text messages, but also encompasses message broadcasting, chatting and even e-mail.
When cellular operator started business, they offered SMS as a free service to attract customers. Today, however, it’s become so popular that a major chunk of revenues for the operators come form SMS. The Short Message Service(the full-form is not that short!) is the happening thing in communication today, being used by people of all ages to send simple 160 character messages. However, there’s a lot more you can do with SMS than that.
CHAT ON THE MOVE
Chat has expanded from being just PC-based to cellphone based. Similar to web-based chat(where you have a chat room and users in the room, with public and private messages passing across), SMS chat lets you chat in a room/community of people.
Yahoo.com extended its desktop-based Yahoo Messenger to cellphones a while age. Using this, you can log onto your Yahoo Messenger even while you are away from your PC. To log onto you Yahoo Messenger, send the following message(without quotes), “In Yahoo ID password”, to the number 8242. To get your list of contacts at any time, send “get’ to the same number. To logout, simply send “out” to the same number. Once enabled, others will see a message, “I’m on SMS”, against your name in their buddy list.
Another interesting feature, depending upon your handset, is group SMS, or sending the same message to multiple users. This function is normally found in the message sending options. For the latest Nokia phones, after you have composed your message, you get a “send to many” option.
SEND AND RECIVE E-MAIL
If you did not know already, your cellphone is capable of sending and receiving e-mail, too. This service uses the same channels as regular SMS. All cellphones have an e-mail id, which is of the form your_number@servicer_provider_email_domain. For example, a Hutch phne subscriber in Delhi would have an e-mail id as subscriber_number[at]delhi.hutch.co.in (or your_number[at]airtelmail.com for an Airtel connection). Anyone connected to the internet, therefore, can send you an SMS from his mail client. You can also send an e-mail from you cellphone. The format and number to which it has to be sent varies for different operators. For Hutch Delhi, for instance, you have to send a message to 121882 in the following format: MAIL<receipitent’s_mail_id><message>. For Airtel Delhi, you need to type the recipient’s e-mail id followed by the message and send it to the number 600. The message is delivered through the service provider’s e-mail gateway to the recipient’s mailbox.
The future has a lot in store for SMS, such as the ability to send pictures, melodies and animation along with text using a technology called Enhanced Messaging Service(EMS). Another similar technology is Multimedia Messaging Services (MMS), which will require a lot of changes to a service provider’s network.
SMS SENT….WHAT HAPPENS NEXT ?
The Short Message Center (SMC) receives messages from handsets and does the necessary forwarding. After receiving the message, it interacts with the Home Location Register (HLR) to check the current status of the cellphone that the message was sent to. HLR is the main database that holds the subscription profile and routing information of every subscriber. After finding the location. The message passes to the Mobile Switching Center (MSC), which switches the connection between the mobile cells. A visitor Location Register (VLR), which corresponds to every MSC, stores information about the mobile identification and location. After switching, the message gets passed to the Base Station System (BSS).
The BSS then sends the SMS to the receiving handset. The message gets passed through singnaling channels, so that your handset can receive the SMS even in the middle of voice or dat call.
STAY CONNECTED
There are a few things that I’m always with: mobile phone, PDA and PC. Being in the kind of work I do, I need to communicate with my clients all the time. If not meeting them, I establish a ‘remote communication protocol’ through e-mail or voice calls! And this is where the devices I have help me make sure everything goes well.
My nokia 6310, an enhanced version of the very popular 6210, is the newest entrant to my communication devices, its battery, overall weight, sleekness and myriad features made me quite pleased with my decision to buy it.
The cellphone has an infrared port at the top, which I use for communicating with my palm. Once I turn on the IR, I can use my phone as a modem and dial into my ISP as normal. I then use an IMAP e-mail client and a Web Browser on my Palm to send, receive and manage e-mail as well as browse the Web (in text mode). Also, unlike earlier, the data service seems to have been made free for use and is charged only as per normal outgoing airtime rates, no extra monthly charges for it. Of course, you will have to check with your service provider to see if that is true for you too.
My favorite is checking mail just before going to bed without turning on my computer. Switching on the palm takes a illisecond and dialing up through the mobile is fast. Other things I do over IR are sending new operator/calling group logos and ring tones to my phone as well as managing my phone book on the mobile.
MAKE IT SECURE
Cellphones come with a lot of security features that restrict the use of the phone to unauthorized people and unwanted calls. The phone’s serial number, lock code, PIN, PIN2, PUK, PUK2, SIM lock are a few of these great features.
With the help of a phone’s serial number (also called the IMEI number –International Mobile Equipment Identity), the network operator can track the phone and switch its services off f it is stolen or lost. IMEI is a unique 15-digit code that identifies your handset to the service provider. You can look up your IMEI code by typing *#06# on you key pad.
The four-digit phone lock code restricts answering to all incoming calls and allows you to make only emergency calls. This is factory set to 0000. You can change it to you own code.
The PIN (Personal identification Number, also called the PIN1, depending on your handset) protects the SIM against unauthorized use and allows access to various other phone features.
When enabled, you need to enter it each time the phone is switched on. If entered incorrectly three times in succession, the handset locks itself. To reactivate the handset in such a case you have to use the eight-digit PUK (Personal Unblocking Key) provided by the service provider. Further if the PUK is entered incorrectly 10 times in succession, your SIM gets deactivated completely. You cannot change the PUK yourself.
The PIN2 is supplied by some SIM cards only and is required to access specific functions, like call cost counters, barred dial, call charge metering and fixed dial store. Similar to the PIN the PIN2 gets deactivated if entered incorrectly three times in succession. An eight-digit PUK2 number provided by the service provider is used to reactivate it. The PUK2, if entered incorrectly 10 times in succession, renders the SIM useless.