04-06-2013, 03:26 PM
MULTI USER SECURITY FOR MULTI CAST COMMUNICATION
MULTI USER SECURITY.pptx (Size: 2.37 MB / Downloads: 17)
INTRODUCTION
The simplest computer chatting is a method of sending, receiving, and storing typed messages with a network of users. This network could be WAN (Wide Area Network) or LAN(Local Area Network). Our chatting system will deal only with LAN’s (static IP address) and it is made up of two applications one runs on the server side (any computer on the network you choose it to be the server) while the other is delivered and executed on the client PC. Every time the client wants to chat he runs the client application, enter his user name, host name where the server application is running, and hits the connect button and start chatting. The system is many-to-many arrangement; every–one is able to “talk” to anyone else. Messages may be broadcasted to all receivers
(recipients are automatically notified of incoming messages) or sent to special individuals (private chatting through server) where during this operation all messages are encrypted at the sender side and decrypted at the recipient to disallow any hackers to the server from reading these private messages.
objective & Scope of the Project
The system is proposed is user friendly. This provides a graphical user interface. Here we providing the visual effects which reduce the inefficiency of the existing one by providing appropriate message and data entering such as textbox, button etc.
The software can be used by any one who has the knowledge about the computer a little bit. The user does not meet any complication by using the system, as it satisfies their needs. The system done within sight in to the necessary modification that may be required for the future. The system is user friendly, compatible, quick responding, providing the accurate information.
SYSTEM ANALYSIS
Introduction
Systems analysis is the interdisciplinary part of Science, dealing with analysis of sets of interacting entities, the systems, often prior to their automation as computer systems, and the interactions within those systems. This field is closely related to operations research. It is also "an explicit formal inquiry carried out to help someone, referred to as the decision maker, identify a better course of action and make a better decision than he might otherwise have made.
That part or aspect of systems analysis that concentrates on finding out whether an intended course of action violates any constraints is referred to as FEASIBILITY analysis. A systems analysis in which the alternatives are ranked in terms of effectiveness for fixed cost or in terms of cost for equal effectiveness is referred to as COST-EFFECTIVENESS analysis. COST- BENEFIT ANALYSIS is a study where for each alternative the time stream of costs and the time stream of benefits (both in monetary units) are discounted to yield their present values. The comparison and ranking are made in terms of net benefits (benefits minus cost) or the ratio of benefits to costs.
Feasibility Analysis
A Feasibility Study is a process which defines exactly what a project is and what strategic issues need to be considered to assess its feasibility, or likelihood of succeeding. Feasibility studies are useful both when starting a new business, and identifying a new opportunity for an existing business. Ideally, the feasibility study process involves making rational decisions about a number of enduring characteristics of a project, including:
• What exactly is the project? Is it possible? Is it practicable? Can it be done?
• Economic feasibility, technical feasibility, schedule feasibility, and operational feasibility - are the benefits greater than the costs?
• Technical feasibility - do we 'have the technology'? If not, can we get it?
• Schedule feasibility - will the system be ready on time?
• Customer profile: Estimation of customers/revenues.
• Determination of competitive advantage.
• Operational feasibility - do we have the resources to build the system? Will the system be acceptable? Will people use it?
• Current market segments: projected growth in each market segment and a review of what is currently on the market.
• Vision/mission statement.
• Definition of proposed operations/management structure and management method
Legal feasibility
Determines whether the proposed system conflicts with legal requirements, e.g. a Data Processing system must comply with the local Data Protection Acts. When an organization has either internal or external legal counsel, such reviews are typically standard. However, a project may face legal issues after completion if this factor is not considered at this stage.
Operational feasibility
Is a measure of how well a proposed system solves the problems, and takes advantages of the opportunities identified during scope definition and how it satisfies the requirements identified in the requirements analysis phase of system development.
Schedule feasibility
A project will fail if it takes too long to be completed before it is useful. Typically this means estimating how long the system will take to develop, and if it can be completed in a given time period using some methods like payback period. Schedule feasibility is a measure of how reasonable the project timetable is. Given our technical expertise, are the project deadlines reasonable? Some projects are initiated with specific deadlines. You need to determine whether the deadlines are mandatory or desirable.
Input design
The input design is the process of converting the user-oriented description of input to the computer based business information system into a program-oriented specification. The objective of input design is to create an input layout that is easy to follow and prevent operator errors. It covers all phases of input right from creation of initial data into actual entry of data to the system for processing. The input design is the tool that ties the system to the world of its users.
Input design is mainly concentrated on estimating what the inputs are and how they have to be arranged on the input screen, how frequently the ideas are to be collected.
The input screens are designed in such a manner that avoids confusion and guides the user in the correct track. Although study has been made on the type and how the input form is to be designed. Some inputs from the user may cause severe error and is strictly validated.
The layout of the input screen is also taken into account. A very good look and feel is provided through the organized arrangement of controls such as menus, buttons etc.
Input screen are very simple and user friendly. Users are allowed to access the software only after the authentication process.
Output design
The output design generally refers to the results generated by the system. For many end-users, output is the main reason for developing the system and the basis on which they evaluate the usefulness of the application. The objective of a system finds its shape in terms of the output. The analysis of the objective of a system leads to the determinations of outputs. The most common type of output is screen displays. The output also varies in terms of their contents, frequency, timing and format. The users of output, its purpose and sequence of details to be printed are all considered. if the outputs are inadequate in any way, the system itself is inadequate.
Database design :
Database design is the process of producing a detailed data model of a database. This logical data model contains all the needed logical and physical design choices and physical storage parameters needed to generate a design in a Data Definition Language, which can then be used to create a database. A fully attributed data model contains detailed attributes for each entity.
The term database design can be used to describe many different parts of the design of an overall database system. Principally, and most correctly, it can be thought of as the logical design of the base data structures used to store the data. In the relational model these are the tables and views. In an object database the entities and relationships map directly to object classes and named relationships. However, the term database design could also be used to apply to the overall process of designing, not just the base data structures, but also the forms and queries used as part of the overall database application within the database management system (DBMS).
Data storage
The main unit of data storage is a database, which is a collection of tables with typed columns. SQL Server supports different data types, including primary types such as Integer, Float, Decimal, Char (including character strings), Varchar (variable length character strings), binary (for unstructured blobs of data), Text (for textual data) among others. It also allows user-defined composite types (UDTs) to be defined and used. SQL Server also makes server statistics available as virtual tables and views (called Dynamic Management Views or DMVs). A database can also contain other objects including views, stored procedures, indexes and constraints, in addition to tables, along with a transaction log. A SQL Server database can contain a maximum of 231 objects, and can span multiple OS-level files with a maximum file size of 220 TB. The data in the database are stored in primary data files with an extension .mdf. Secondary data files, identified with an .ndf extension, are used to store optional metadata. Log files are identified with the .ldf extension.
Buffer management
SQL Server buffers pages in RAM to minimize disc I/O. Any 8 KB page can be buffered in-memory, and the set of all pages currently buffered is called the buffer cache. The amount of memory available to SQL Server decides how many pages will be cached in memory. The buffer cache is managed by the Buffer Manager. Either reading from or writing to any page copies it to the buffer cache. Subsequent reads or writes are redirected to the in-memory copy, rather than the on-disc version. The page is updated on the disc by the Buffer Manager only if the in-memory cache has not been referenced for some time. While writing pages back to disc, asynchronous I/O is used whereby the I/O operation is done in a background thread so that other operations do not have to wait for the I/O operation to complete. Each page is written along with its checksum when it is written. When reading the page back, its checksum is computed again and matched with the stored version to ensure the page has not been damaged or tampered with in the meantime.