Verbal Communication is one of the most important forms of communication in the world with real world situation. With it one can interpret many things in message from tone of voice, pitch and content. Voice chat is a tool with which one can communicate with friends and member and can communicate fastly and easily .The means of communicating with voice chat has led to a significant increase in distant communication where two or more people from opposite end of the world. This paper describes a research based case study of voice chat. Best practice Software Engineering methodologies are used to specify and design of voice chat box (voice over IP system) [1, 2]. The methodologies utilise are the Unified Modelling Language (UML), and the project specification explored their combined use .
The voice Chat (VOIP) system implemented Called ‘Network2012’, will allow user to communicate via voice, as well as several other already existing features with under construction web application www.network2012.net .
Index Terms- VOIP, UML, Client-server working, Software Engineering,
2.1 What Voice chat is?
Voice chat (known as PC to PC call+ Instant Message) is one of two telephony capabilities that are debuting in the same time IM client. The other is click-to-call (also called click-to-dial), which allows a user to instantly create a telephone conference with one user. In both cases, a user invites other user in a chat window or on the buddy list to join a call, and the invitee is given the opportunity to either join or decline. A user who chooses to join is connected to the call. If voice chat is used to initiate the call then user communicate using own computer's microphone and speakers .
3.1 Underlying Principle:-
There is a large number of voice chat and IM users. According to ‘skype.com’ and ‘skype.net’ concurrent graph of Skype user shows , there are total 42,153,766 ‘Real Users’ registered to only ‘Skype Voice chat tool’ . A common issue with a client to client communication is the network and the client – level firewall that block incoming connection to random ports . While a client to client connection session to the negotiate client to client UDP VOIP link. Most probably firewall obstruct voice connection with router or with client because of security reasons [6, 9].
Users, looking for best facility and are demanding more technology, mostly young generation looking for more and more technology for better life standard and for better convenient. Although routinely new application coming in modern world in daily life, with more advanced features and facility.
This paper mainly focuses on the real time based voice chat tool for a real time based company, so I will discuss designing process of voice chat tool.
Most of voice chat support files transfers in integrated environment. While servers are involve in the initial establishment of the voice call, many communication processes are often done between end users (clients) directly in a point to point (peer to Peer). While if user is offline then Voice message buffered to server and delivered when those users come online. .
The objective of this study is to study and design ‘(Implementation will be submitted with final Dissertation project)’ a ‘voice chat’ API for a real time based “Social Enterprise Charity Company, Network2012”, located at ‘1 Greek Road, W1D 4NQ, London’. The idea of the Project is to study and design use cases, flow charts, sequence diagrams, class diagrams and charts related to this web application tool. This paper discusses the buddy –list model of the internet voice chat [3, 4].
Theoretically study of voice chat functions.
Working of voice chat function with internet protocols.
Designing of Web Interface based voice chat tool for Social Enterprise , charity Based Company ,”Network2012” Located at ‘1 Greek Road, W1D 4NQ, London’.
5. Literature Survey:
There are so many web application voice chat tools, Instant messaging tool and voice messaging tools made by software developers with their comparative analysis. They also analyse the main functioning of the application/ software depending upon requirements and configuration of the tool. Although these papers show mostly main functioning of the application, it does not detail the ‘voice chat’ architecture, and main obstacle.
Configuring Cisco Voice Over IP [Syngress 2002], , represent the basic model of the voice functioning over IP with internal architecture of the internet working and about the architecture of the web click on call function with softphone configuration.
Voice Over Internet Protocol Architecture and features [lulu.com], , details the architecture of the various protocols and functioning of the protocols and feature of the voice functioning with the protocol. It explains the H.323 protocols and collaboration with different protocols.
While working with VOIP , we should have to consider about IP functions and appropriate Internet protocol which have to use and have to consider for IP interlinks , from last scenario , it being seen most of professional uses UDP protocol for voice transferring , tells about the basic UDP protocol.
EVVCM [Dec 2008], , shows, VOIP (voice chat) is vulnerable to network congestion if too many users access the web services based IP at the same time. VOIP signalling is usually implemented on UDP.Since UDP can’t verify the packet arrival, so that some there is problem of packet lost or delay in receiving to destination.
Bruegge, Dutoit , explained about the software designing about UMl diagrams, about Use cases and structure and step to step configuration of the software. This books review the main concepts and about the structural process of the software and about how to flow from one step to another.
IBM[ lotus], explain the client –server architecture of the voice chat, it explain the working of the voice chat over IP and how they communicate with other protocols and the function of the same time voice chat functions.
IBM [lotus] explains voice chat functions of peer to peer and reflector connection and about the ports requirements.
6. Key Paper Review:-
Physical Configuration of Voice Chat.
To place a voice call using VOIP there are three different ways “Flavors”.
ATA (Analogue Telephone Adapter).
6.1.3 Computer to Computer. (Voice Chat).
In this Paper Review I discuss Computer to computer mean Voice Chat. .
This part of paper, concentrated mainly on basic and internal working of the voice chat how this interact with other client with the help of protocols and hyper text transfer protocol. The audio (voice chat) services support interactive IP audio capabilities and enables client with the appropriate hardware (sound card, Microphone, speaker) to transmit and receive real time audio during client – server communication at the same time. While with voice chat and click to call option, a user invites other user in a chat window and invitee and given the opportunity to join or decline the request from the end client.
Voice chat works with ‘User Datagram protocol (UDP) Packets’ at later 4 then TCP, which flow through UDP ports on the firewall of the every client machines to enable user to conduct oral chats with other user over their computers. The client machines use a single port (UDP), so that this port should be open for both incoming and outgoing calls and voice (UDP traffic) .
Fig 1. IP protocol Stack for VOIP. Fig 2. VOIP layers.
Voice chat uses Packet switch solution then Circuit switch solution. In circuit switch networks a line of communication must exists to communicate voice. On the Other side Packet switching uses packets to deliver Data and Voice over IP.Voice can be transported with much less bandwidth less than 64kps then circuit switched Networks.
In packet switching network data are transmitted in blocks and chunks, called packets. A packet length can be varying from 1000 octets to bytes. If a source has to send large amount of Data the if be broken into small packets and transferred to destination with the address of source and destination to control the packets, after shorting all packets information send to destination.
Fig 3.Architecture of packet switches Network .
6.3 Problems with UDP:
The problem is that how to ensure the reasonable voice quality, and recover packet loss? But UDP does not offer voice quality and packet loss recovery at physical level. So that we need more than UDP offer, so that destination must aware about the coding technique at source platform for decoding . To solve this problem and for the recovery of the packet loss we uses ‘Real Time Transmission Protocol (RTP)’and ‘Real time Control Protocol( RTCP)’ for better transmission and recovery of small packets if lost. [ ; 11] contains more information about packet recovery and protocol such H.323, and fast recovery of packets and architecture of the protocols.
Designing Process of “Network 2012” Voice chat:
6.4.1 Functional Model of “www.network2012.net”.
Fig 4. Main Functional Flow.
In this Paper Fig. 4, consist the main functional diagram of the www.network2012.net .while ‘The Red part’ consists the main area of the study, and my work of design and implementation (Final Project). After studying and analysing the main area I made UML diagrams of the site.
Use Case :
Logon use case structure:-
Fig 4: Use Case Diagram for User Login.
This diagram shows user should be logon before entering to voice chat tool with existing username and password otherwise register with the application first . After submitting username and password application must check record in Database if exists then send to voice chat tool otherwise send to register page.
Voice Chat use case Structure:-
Fig 5. Use case diagram for voice chat functioning.
According to Voice chat use case, after user logon ‘user 1’ request call function of voice chat to ‘user 2’. If ‘user 2’ accept call then ‘user 1’ connected to ‘user 2’ with the help of ‘client-server’ configuration.
Sequence Diagram: -
Voice chat Logon Function:-
Fig 6. Sequence Diagram Of login Function.
According to diagram ‘user’ send request first for login to web application voice chat tool, GUI or Home Page make link with application and retrieve form from web, and after submission of form it send back to server and Database matches the ‘Email/Username’ and ‘password’ with existing data if it matches existing data then allow user and provide services to user , otherwise through back to logon screen if one of either ‘email id or username’ of theif user is new then through to register page and allow user to register first with the application and after successfull registration , application send email to existing email id of the user with username and password.
Voice Call To Members:-
Fig 7. Sequence Diagram for voice call set up.
After logon user 1 sends call request to user 2 with web application internal connectivity,interface alert user 2 about incoming call and provide choice about either accept or ignore the call,[Above diagram is about call acceptance] . if user 2 accept call then server webapp make confirmation to user1 and user 2 for connection confirmation, and send responce back to user1. Then user 1 send chat and voice data which is stored to database and at the same time user2 get data from database and voice from the database and protocol.
But what happened if one of online want to make a call to a offline member, at this situation you can send a voice mail to a member which will go to inbox of the member and store voice data to database and alert member with an email in the member’s inbox with voicemail player, so that he can get his voicemail.
Sequence Diagram for voice mail:
Fig 8. Sequence Diagram for Voice Mail Storing to Database.
According to this sequence diagram User 1 send request to offline member, as member is offline so that web application make connection to database account of the offline member and a voicemail recorder to user1 , so that user can record his/her message. After recording voice data stored to database and an email confirmation with voice data link send to offline member’s id, from there can retrieve voice message.
7.Focused Topic Appraisal:
According to this application classification the main focus is upon the implementation and working of the voice chat for social Enterprise company www.network2012.net. There are many voice chat tools which works over IP, with many configuration and protocols. For voice chat many factors are to be consider:
High speed Internet.
A high speed Internet is required(DSL, Cable Modem , TI, etc.) if voice transaction is to be used in the corporate and indivisual need.
In the event of power loss , lost of voice packet occure.
VOIP is difficult to transform or inter-act other service provider because of some service provider plans that you can call only those with the same service provider and with the same software.
Multiple number of user.
To run multiple number of lines , you must have DSL router, which can connect to different IP.
As voice chat works over IP address , which are already have hacking , virus and spam problems, therfore same problems occure with voice chat tool ( VOIP).
With the help of this paper propose the understanding of the basic characterization designing model of the voice chat and how voice chat works with the real world system. This paper also tells about the basic networking protocols which should be consider essential for voice chat. With the help of skype calculator refrence we got to know how many user are online and register to just single instant messanger with call functioning and with other services.
9.Personal Recommendation for further Investigation:
After analysing voice chat and studying a lot about voce over Internet Protocol i would like make further reserch on voice chat on these factors.
Translation of one language to another at same-time while doing chatting on same platform.
Translation of one language voice to another language voice so that by choosing different language speaker to another.
Business benefit :
If we consider above two factors ther will be many benefits from this research.
Poeple who know different language can enjoy chat function in their own language.
Poeple from different language can speak in their own language and can talk to different language poeple without any more knowledge of another language .
Fig 8. Language Voice Translator [Future Research Basic Model.]
The Basic voice chat architecture in the Real world
Fig 9. Virtual client–Server Architecture.
According to this architecture, When chat client 1 send anlog voice + data to client 2, this method first converted at “ATD/DTA encoder /decoder” i.e. Analog to digital signal and send to the networking platform , where with the help of IP protocol(TCP/UDP/H.323) encrypted and a 16-63 hexadecimal key is added with this signal for security purpose and send to server , at the same time chat client 2 make request to the server and get data from server where this signal decrypted at networking platform with same technique and response send to the client2 vice-versa.
Fig 10.Basic Working architecture of the protocol H.323 call established.
Fig. 11 A proposed Software and Hardware architecture.
As this proposed architecture is belong to real time based working “Network2012” social enterprise company, that’s why I have to use HTML and PHP at software platform because of boundation of the company. Well for voice transportation and better security Java platform will be used (in future).
These papers discussed different aspects of the voice chat and about the protocols which are used in the VOIP techniques. The positive outcome of this research is that it tells about existing technology and force to think about real world situation which are more possibly can allow with these technologies. After analysing these paper most will get to review the functions and basic design process of voice chat. Moreover why protocols UDP + TCP at layer 4 are more secure while making connection to other client?
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