BASIC CALL FLOW IN GSM

Hi friends,

Iam very happy  to meet you guys again. Now coming into the todays blog.

Generally, we are all using mobile phones to communicate with out-stationed persons.

You people know,how much time it takes to originate/make a call !!!! Its fraction of seconds...

Do you know ,For originating a call ,how much process it may takes place.

Let's go and Learn.....!!!!

Basic Call Setup in a GSM Network :

            Setting up a call between two communication devices seems very quick and very simple operation,but when we look deeper in to this and analyse this then we can understand that a lot of operations are happening with in a short span of time.

Before going deep in to this first i will give a brief introduction of various elements included in this process.

1.BTS-BTS stands for Base Transceiver Station.It is nothing but your Tower which radiates the signal to your mobile.It is the first player in this operation which always have a touch with the mobile.

2.BSC-BSC stands for Base Station Controller.It is a large unit which controls all the BTS(Towers).We can say that a number of BTS are controlled by a single BSC.There are so many BSCs present in an area depending on the number of users and all are inter connected.

3.MSC-MSC stands for Mobile Switching Center.It is responsible for switching the call to the called subscriber.A number of BSCs are connected to the MSC and it controls the BSC.

4.HLR-HLR stands for Home Location Register.It is the server which stores the details of the all the subscribers permanently.

5.VLR-VLR stands for Visitor Location Register.It is the server which stores the details of the all the visiting subscribers temporarly.

All the above said units are interconnected and plays a vital role in call connection.

Call Setup  :


1.When a subscriber initiates a call by dialling a number in his mobile it directly send a request to the BTS which he comes under.

2.BTS there by sends the request to the BSC to which it is connected.

3.From the BSC the request is made to the MSC to which it is connected.

4.Then MSC sends a request to the HLR to check the information about the caller like account balance(if pre paid),live user,area of the caller etc.

5.After checking all the details the HLR sends a acknowlegement message to the MSC that the caller is O.K. to make a call or not.

6.If that message is O.K. the operation continues or else the MSC sends a NOT O.K. message to the BSC which has made the request and BSC to the BTS and BTS to the Mobile.At the next instance the call get disconnected.

7.If the message recieved by the MSC is O.K. then it again sends a request to the HLR to find the called party(the subscriber to whom call is made).

8.The called party and the caller may comes under the same MSC or different MSC.If both comes under the same MSC then the HLR finds the subsciber easily and informs the MSC that to which area the called party belongs.The MSC therefore establishes a air link between the both parties.Thus the call gets connected.

9.If both parties comes under different MSC then the HLR again search for the MSC to which the called party belongs and inform the same to the MSC of the caller.Thus the MSC of the caller establishes a air link between the both parties.Thus the call gets connected.

After the call gets disconnected the Billing is made the Billing Server which is present in the HLR.

Thankyou friends,

Murali krishna Athipatla
Core Network Engineer
ZTE Telecom India Pvt Ltd
9094737994

INTRODUCTION TO JAVA FOR ALL JAVA BEGINNERS....

J    A   V    A

-the beginning

                                 

Introduction :

• JAVA was developed by Sun Micro systems Inc in 1991, later acquired by Oracle Corporation.
• It was conceived by James Gosling and Patrick Naughton. It is a simple programming language.
•  Writing, compiling and debugging a program is easy in java.  It helps to create modular programs and reusable code.

Main Features of JAVA : JAVA is a platform independent language.

•  To understand the meaning of platform independent, we must need to understand the meaning of platform first.
• A platform is a pre-existing environment in which a program runs, obeying its constraints, and making use of its facilities.
• During compilation, the compiler converts java program to its byte code. This byte code can run on any platform such as Windows, Linux, Mac/OS etc. Which means a program that is compiled on windows can run on Linux and vice-versa.
• This is why java is known as platform independent language.

JAVA is an Object Oriented Language :

      Object oriented programming is a way of organizing programs as collection of objects, each of which represents an instance of a class.

• 4 main concepts of Object Oriented programming are:

1. Abstraction
2. Encapsulation
3. Inheritance
4. Polymorphism

• Java is considered as one of simple language because it does not have complex features like Operator overloading, Multiple inheritance, pointers and Explicit memory allocation.

Robust Language :

Two main problems that cause program failures are memory management mistakes and mishandled run time errors. Java handles both of them efficiently.

1) Memory management mistakes can be overcome by garbage collection.  Garbage collection is automatic de-allocation of objects which are no longer needed.

2) Mishandled run time errors are resolved by Exception Handling procedures.

Secure :

It provides a virtual firewall between the application and the computer.  Java codes are confined within Java Run time Environment (JRE) thus it does not grant unauthorized access on the system resources.

JAVA is Distributed :

• Using java programming language we can create distributed applications. 
• R M I(Remote Method Invocation) and E J B(Enterprise Java Beans) are used for creating distributed applications in java.
•  In simple words: The java programs can be distributed on more than one systems that are connected to each other using internet connection.
•  Objects on one J V M (java virtual machine) can execute procedures on a remote 

J V M.

Multi-Threading :

Java supports multithreading. It enables a program to perform several tasks simultaneously.

Portable : 

JVM

• As discussed above, java code that is written on one machine can run on another machine. 
• The platform independent byte code can be carried to any platform for execution that makes java code portable.

For more tutorials of JAVA ,Please visit the following websites/links.

         www.tutorialspoint.com/java

         javabeginnerstutorial.com/core-java

         courses.caveofprogramming.com/courses/java-for-complete-beginners

Thank you for reading my Blog.

MURALI KRISHNA ATHIPATLA,

  

Email : amkrishna1992@gmail.com

Mob : 8520973796

How to Develop an Android Application With out any

 Programming Background.

Hi Friends......Are you ready to become a Programmer. Don't worry about your professional background.

Get ready to develop a your application on your own.

There are many websites for making Android Applications like APPSGEYSER etc...

1. Initially open the given link .http://www.appsgeyser.com/  
   

     2. Then click on  "CREATE". 

     

     3. Before creating an Application you have Login or Signup into Appsgeyser by using your Email 

          and Password.

     

     4. After logging in into your account ,you have to click on "CREATE".

     5.  Select which type of application you want to buildup (like Messenger,Browser,Website,Etc...).

     6.  Click any one of your selected ICON.

  

     7. After selecting an certain Icon,the "APP SETTINGS PAGE" will open.

  

    8. Suppose if u select BROWSER, you have to Manipulate (Style, Links,Reading Mode settings)

       

         as you like.

    9. Finally SUBMIT your application and PUBLISH it ,if your are interested.

    10. Open your application on your Android Mobile.

           For clear explanation about this blog...please watch my Video...

                                  Thank you for watching my Blog.

MURALI KRISHNA ATHIPATLA

Android Developer,

E-mail : amkrishna1992@gmail.com

Mob : 8520973796