Mailman-A Complete Mail Server

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Mailman-A complete mail server

A Project Report

Submitted in partial fulfilment of

the requirements for the award of the degree of

Master of Technology in

Computer Science and Engineering

by

Prasanth.R.S

M105111

Department of Computer Science & Engineering

College of Engineering TrivandrumKerala - 695016

2010-11



College of Engineering TrivandrumDepartment of Computer Science & Engineering

Certified that this Project Report entitled

Mailman-A complete mail server

is a bonafide record of the project presented by

Prasanth.R.SM105111

in partial fulfilment of the requirements for the award of the degree of

Master of Technology in

Computer Science & Engineering

Mr.AnvarGuide

Asst. Professor

Dept.of Computer Science & Engineering

Dr. M.S RajasreeProfessor and

Head

Dept.of Computer Science & Engineering



Acknowledgement

I would like to express my sincere gratitude and heartful indebtedness to my guide MrAnvar, Asst. Professor, Department of Computer Science And Engineering for his valuable

guidance and encouragement during the course of preparation and presentation of this projectreport.

I am thankful to Dr. M S Rajasree, Head of the Department, Shine S, P.G Coordina-tor, Shreelekshmi R, Asst. Professor and Rameez Mohammed,Lecturer Department of Computer Science and Engineering for their help and support.

I also acknowledge my gratitude to other members of faculty in the Department of ComputerScience And Engineering and all my friends for their whole hearted cooperation and encour-agement.

Above all I am thankful to God Almighty.

Prasanth.R.S

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Contents

1 Introduction 5

2 SMTP(Simple Mail Transfer Protocol) 62.1 SMTP Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3 SYSTEM ANALYSIS 93.1 Product Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2 System Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2.1 Hardware Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2.2 Software Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4 TOOLS 104.1 About ASP.NET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.1.1 .NET Framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.1.2 Common Langauge Runtime (CLR) . . . . . . . . . . . . . . . . . . . . . 114.1.3 C Sharp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.2 DBMS Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124.2.1 SQL Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.3 Features of OS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134.3.1 Microsoft Windows 2000 Server . . . . . . . . . . . . . . . . . . . . . . . 134.3.2 Internet Information Server 5.0 . . . . . . . . . . . . . . . . . . . . . . . 13

5 Design Notations 15

5.1 Data Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

6 Conclusion 17

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Abstract

Mailman is a mailserver which is an easy way of transferring mails. An e-mail server is acomputer within our network that works as virtual post office. A mail server usually consists

of a storage area where e-mail is stored for local users, a set of user definable rules whichdetermine how the mail server should react to the destination of a specific message, a databaseof user accounts that the mail server recognizes and will deal with locally, and communicationsmodules which are the components that actually handle the transfer of messages to and fromother mail servers and email clients.

The system is intended to be a complete email server, with some extended features whichwill enable the users of the system to seamlessly communicate with each other through emails.It is developed as a secured email server which manages the sending and receiving of emailsby the registered users of the system in a way that enforces the security. Security is provided

by using encryption and decryption. It encrypts password and message while sending and inthe receiving side it decrypts the message. Hence high security is provided for users passwordsand messages.It also includes the advanced features like status tracking, which means that,users can know whether the recipient has read the mail or deleted. There are four status.They are read, unread, read and deleted and unread and deleted. Users can know the statusof the mail after sending.It also contains another feature, chatting. By using on-line chatting,users can seamlessly communicates by sending and receiving messages.It also includes a featurelike deleting of mails after a particular date. Senders can send mails with mail destroyingdate. When the mail reach the particular date which is already set is automatically removedfrom the inbox of the recipient whether it is read or unread.In the Login link a user have to

login for transferring mails. Next page provides several links. The Home page contains severallinks such as my settings, Inbox, Compose, Trash, My folder, Sent Items, spams,Address Bookand Logout.User can add new contacts and signature The user can create new mails and sentto other user or group of users.An already registered user can simply type in his/her validusername and password, and then click the ”submit” button. But those visitors who are notregistered have to go to the registration page before they login. In that page user have to enterFirst name, Last name, Address, Postal Code, City, Phone number, Username and password.After registration user can sign in and check or send mail . Logout link will help the user tologout from the site.

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1 Introduction

E-mail server is a computer within our network that works as virtual post office.A mailserverwhich is an easy way of transferring mails.Emails were an easy way to notify end-users of busi-

ness events in an application. With the emergence of new notification channels (such as WAPPhones, Instant Messaging applications, and SMS Pagers), sending notifications has becomemore complicated. Now, applications have to support an ever- changing set of communicationchannels that end users would like to be notified on. Additionally, once developers have finishedbuilding the communication mechanisms, they will also need a way of determining where tocontact an end user at what time (i.e. should an email be sent to the users PC).

An email box (also email mailbox, e-mailbox) is the equivalent of a letter box for electronicmail. It is the destination where electronic mail messages are delivered.A mailbox is identifiedby an email address. However, not all email addresses correspond to a storage facility. The term

pseudo-mailbox is sometimes used to refer to an address that does not correspond to a definitivemail store. Email forwarding may be applied to reach end recipients from such addresses.Electronic mailing lists and email aliases are typical examples.The term mailbox refers to thatdepository. In that sense the terms mailbox and address can be used interchangeably.

An Email client retrieves messages from one or more mailboxes. The database (file, directory,storage system) in which the client stores the messages is called the local mailbox. Popularprotocols to retrieve messages are:

• Post Office Protocol:- A client-server method that is most suitable for reading messagesfrom a single client computer because message are removed from the server mailbox afterfirst retrieval.

• Internet Message Access Protocol:- Designed to retrieve messages from multiple clients byallowing remote management of the server mailbox by keeping master copies of messageson the server but can save a copy in the local mailbox.

Web-based clients exist that retrieve messages from the server on behalf of the website userand display them to the user in a suitable format in a web browser.

Any kind of database can be used to store email messages. However, some standardization

has resulted in several well-known file formats to allow access to a given mailbox by differentcomputer programs. There are two kinds of widely used formats:

• Mailbox is the original technique of storing all messages in a single file,

• Maildir is a newer specification that provides for storing all messages in a directory tree,with one file for each message.

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2 SMTP(Simple Mail Transfer Protocol)

SMTP or Simple Mail Transfer Protocol is a way to transfer email reliably and efficiently.SMTP is a relatively simple, text based protocol, where one or more recipients of a message

are specified (and in most cases verified to exist) and then the message text is transferred. Youcan think of SMTP as the language that mail servers use to communicate among themselves.

Since this protocol started out as purely ASCII text based, it did not deal well with binaryfiles. When the user wants to send a message to someone, the sender SMTP establishes a twoway transmission channel to a receiver SMTP. SMTP commands are generated by the senderSMTP and sent to the receiver SMTP. SMTP replies are sent from the receiver SMTP to thesender SMTP in response to the commands. In case a direct connection does not exist betweenthe sender and the final destination, the message may be sent via one or more relay SMTPservers. The relay SMTP servers first act as receivers and then relays the message to the next

SMTP.

SMTP server must be supplied with the name of the ultimate destination host as well asthe destination mailbox name. Once the transmission channel is established, the SMTP sendersends a MAIL command indicating the sender of the mail. If the SMTP receiver can acceptmail it responds with an OK reply. The SMTP sender then sends a RCPT command identifyinga recipient of the mail. If the SMTP receiver can accept mail for that recipient it responds withan OK reply; if not, it responds with a reply rejecting that recipient (but not the whole mailtransaction). The SMTP sender and SMTP receiver may negotiate several recipients. Whenthe recipients have been negotiated the SMTP sender sends the mail data, terminating with a

special sequence. If the SMTP receiver successfully processes the mail data it responds withan OK reply. The dialog is purposely lock step, one at a time.

2.1 SMTP Commands

Given below are some basic commands with their brief descriptions. The SMTP standarddefines many more commands, most of which are optional to implement.

• HELLO (HELO)

This is the first command that is sent when a connection is established. It is used to identifythe sender SMTP to the receiver SMTP. The argument field contains the host name of thesender SMTP.

HELO < SP > < domain > < CRLF >

Note: < SP > stands for a space and < CRLF > stands for a combination of CarriageReturn and Linefeed. The receiver SMTP identifies itself to the sender SMTP in the connectiongreeting reply and in the response to this command.

• MAIL (MAIL)

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There are three steps to SMTP mail transactions. The transaction is started with a MAILcommand which gives the sender identification. A series of one or more RCPT commandsfollows giving the receiver information. Then a DATA command gives the mail data. Andfinally, the end of mail data indicator confirms the transaction.

The first step in the procedure is the MAIL command. The ¡reverse-path¿ contains the sourcemailbox.

MAIL < SP > FROM:< reverse − path > < CRLF >

If accepted, the receiver SMTP returns a 250 OK reply. The < reverse− path > can containmore than just a mailbox. The < reverse − path > is a reverse source routing list of hostsand source mailbox. The first host in the < reverse − path > should be the host sending thiscommand.

• RECIPIENT (RCPT)

This command gives a forward path identifying one recipient. If accepted, the receiverSMTP returns a 250 OK reply, and stores the forward path. If the recipient is unknown thereceiver SMTP returns a 550 Failure reply. This second step of the procedure can be repeatedany number of times.

RCPT < SP > TO:< forward − path > < CRLF >

The < forward − path > can contain more than just a mailbox. The < forward − path >

is a source routing list of hosts and the destination mailbox. The first host in the < f orward−

path > should be the host receiving this command.

• DATA (DATA)

DATA (DATA)

The third step in the procedure is the DATA command.

DATA < CRLF >

If accepted, the receiver SMTP returns a 354 Intermediate reply and considers all succeedinglines to be the message text. When the end of text is received and stored the SMTP receiversends a 250 OK reply.Since the mail data is sent on the transmission channel the end of themail data must be indicated so that the command and reply dialog can be resumed. SMTPindicates the end of the mail data by sending a line containing only a period.The mail dataincludes the memo header items such as Date, Subject, To, Cc, From etc.

• VERIFY (VRFY)

This command asks the receiver to confirm that the argument identifies a user. If it is auser name, the full name of the user (if known) and the fully specified mailbox are returned.

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VRFY < SP > < username > < CRLF >

• RESET (RSET)

This command specifies that the current mail transaction is to be aborted. The receivermust send an OK reply.

RSET < CRLF >

• NOOP (NOOP)

This command does not affect any parameters or previously entered commands. It specifies

no action other than that the receiver send an OK reply.

NOOP < CRLF >

• QUIT (QUIT)

This command specifies that the receiver must send an OK reply, and then close the trans-mission channel.

QUIT < CRLF >

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3 SYSTEM ANALYSIS

Requirement analysis can be defined as a detailed study of various operations performed bya system and their relationship within and outside of the system. One aspect of the analysis

is designing the boundaries of the system and determining whether or not a candidate systemshould other related systems. During analysis data are collected on the available files, decisionpoints and transactions handled by the present system.

3.1 Product Features

The main features of the application are:

• Spam filtering

• Mail sending/receiving

• Status tracking module

• Encryption/decryption of mails

• Contacts management

• chat module

3.2 System Specification

3.2.1 Hardware Configuration

The selection of hardware is very important in the existence and proper working of any software.When selecting hardware, the size and capacity requirements are also important.

• Processors : Pentium 2 or above

• Hard Disk : 40 GB Hard Disk

• RAM : 256MB

• Clock Speed : 550 MHz or above

3.2.2 Software Configuration

One of the most difficult tasks is selecting software, once the system requirements is find out thenwe have to determine whether a particular software package fits for those system requirements.This section summarizes the application requirement

• Language : ASP.NET

• Back End Tool : SQL Server

• Operating System : WINDOWS XP/NT/Vista

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4 TOOLS

4.1 About ASP.NET

•

Microsoft .net is a set of software technologies for connecting information, people, systemand devices.

• An absolutely new programming model - totally objected oriented; grammar/functionalityindependent of each other.

• Simplified and consistent architecture - same development methodology may be appliedacross plethora of languages without performance loss.

• Microsoft .net is a set of software technologies for connecting information, people, systemand devices.

• An absolutely new programming model - totally objected oriented; grammar/functionalityindependent of each other.

• Simplified and consistent architecture - same development methodology may be appliedacross plethora of languages without performance loss.

NET is the combination of Framework, Common Language Runtime (CLR), Class libraries,ASP.NET, Web Services and .NET Enterprise Servers. The means to build the Web the wayyou want it. Everybody is doing Web Services. Enterprise Servers it is the future and nextgeneration of the Internet. Many companies are using Web Services now. With .NET, we thinkthat you have the best platform to host your Web Services.

4.1.1 .NET Framework

• The .NET Framework is a development and execution environment that allows differentprogramming languages and libraries to work together seamlessly to create applicationsthat are easier to build, manage, deploy, and integrate with other networked systems.

• The .net framework is responsible for providing a basic platform for application.

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4.1.2 Common Langauge Runtime (CLR)

The Common Language Runtime is responsible for run time services such as language inte-gration, security enforcement, memory, process, and thread management. In addition, it has

a role at development time when features such as life-cycle management, strong type naming,cross-language exception handling, dynamic binding, and so on, reduce the amount of codethat a developer must write to turn business logic into a reusable component

4.1.3 C Sharp

• C sharp = VB+JAVA (Best of both)

• C sharp is an OOP language

• Developed by Microsoft

• Designed for .net, rather than adapted.

• Simple operator overloading

• Basic statement identical to C++, java.

C Sharp is simple, powerful, type-safe, and object-oriented. With its many innovations, C Sharpenables rapid application development while retaining the expressiveness and elegance of C stylelanguages Visual Studio supports Visual C Sharp with a full-featured Code Editor, projecttemplates, designers, code wizards, a powerful and easy-to-use debugger, and other tools. The.NET Framework class library provides access to a wide range of operating system services andother useful, well-designed classes that speed up the development cycle significantly. The CSharp language is clearly the star of the whole .Net mega-production, with Visual Basic.Net asits sidekick. C Sharp and its ’Java-like’ qualities – such as garbage collection and hierarchicalnamespaces – have received lots of attention.

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4.2 DBMS Description

4.2.1 SQL Server

SQL Server is the native data store of ASP.NET. Every business enterprise maintains large

volumes of data for its operations. With more and more people accessing data for their work, theneed to maintain its integrity and relevance increases. Normally with the traditional methodsof storing data and information in files, the chances that the data loses, its integrity and validityare very high SQL SERVER offers capabilities of both relational and object-oriented databasesystems. In general, objects can be defined as reusable software calls which can be locationindependent and perform a specific task on any application environment with little or on changeto the code.

SQL Server products are based on a concept known as ’ Client Server Technology’. Aclient of front-end database applications also interacts with the database by requesting and

receiving information from the database server. It acts as an interface between the user andthe database. The database Server or back-end is used to manage the database tables optimallyamong multiple clients who concurrently request the server for same data. It also enforces dataintegrity across all client applications and controls database access and other.

Microsoft SQL Server extends the performance, reliability, and quality and ease-of-use of Microsoft SQL Server version 8.00194 Microsoft SQL Server includes several new features thatmake it an excellent database platform for large-scale online transactional processing (OLTP),data warehousing, and e-commerce applications.

The Repository component available in SQL Server version 7.0 is now called Microsoft SQLServer Meta Data Services. References to the component now use the term Meta Data Services.The term repository is used only in reference to the repository engine within Meta Data Services.Microsoft SQL Server features include:

• Internet Integration. The SQL Server database engine includes integrated XML support..The SQL Server programming model is integrated with the Windows DNA architecturefor developing Web applications, and SQL Server supports features such as English Queryand the Microsoft Search Service to incorporate user-friendly queries and powerful searchcapabilities in Web applications.

• Scalability and Availability. The same database engine can be used across platforms rang-ing from laptop computers running Microsoft Windows 98 through large, multiprocessorservers running Microsoft Windows 2000 Data Center Edition. SQL Server EnterpriseEdition supports features such as federated servers, indexed views, and large memorysupport that allow it to scale to the performance levels required by the largest Web sites.

• Enterprise-Level Database Features.

The SQL Server relational database engine supports the features required to supportdemanding data processing environments. The database engine protects data integritywhile minimizing the overhead of managing thousands of users concurrently modifying

the database. SQL Server distributed queries allow you to reference data from multi-ple sources as if it were a part of a SQL Server database, while at the same time, thedistributed transaction support protects the integrity of any updates of the distributeddata.

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• Ease of installation, deployment, and use. SQL Server includes a set of administrativeand development tools that improve upon the process of installing, deploying, managing,and using SQL Server across several sites. SQL Server also supports a standards-basedprogramming model integrated with the Windows DNA, making the use of SQL Server

databases and data warehouses a seamless part of building powerful and scalable systems.These features allow you to rapidly deliver SQL Server applications that customers canimplement with a minimum of installation and administrative overhead.

4.3 Features of OS

4.3.1 Microsoft Windows 2000 Server

Windows 2000 Server The Microsoft Windows 2000 Server operating system includes inte-grated Web and application services. These include Internet Information Services (IIS) 5.0,and technologies such as COM+, Message Queuing, and data access. This combination allowsdevelopers to use a wide variety of programming languages and tools to build applications thatcan easily integrate with existing systems, while taking advantage of emerging technologies. Byintegrating these technologies with enhanced performance, scalability, and reliability, as wellas infrastructure features including Microsoft Active Directory Service and end-to-end security,Windows 2000 provides an application server platform well suited for the next generation of Web-enabled applications.

The Microsoft Windows operating system platform has become a standard foundation forbuilding and deploying software applications. Its broad programming language support, largethird-party developer community, and cost efficiency have helped make Windows the main-

stream business operating system and application server platform. With Windows 2000, appli-cation developers can use the tools and skills they already have write the new Internet-enabledapplications that are increasingly required by businesses.From Web sites to high-volume trans-actional applications, Windows 2000 delivers the productivity benefits of component-baseddevelopment and takes advantage of industry standards for greater interoperability, flexibility,and tools support. These application services are tightly integrated into the operating system todeliver the reliability and manageability that the most demanding traditional and Web-enabledapplications require.

4.3.2 Internet Information Server 5.0

Windows 2000 Server includes the built-in Web service, Internet Information Services (IIS)5.0, which is accessible from popular browsers. IIS 5.0 is the reliable, scalable HTTP portalthrough which Web sites and Web applications communicate with the outside world. IIS 5.0provides all the standard services users expect from a Web server as well as support for thelatest Internet standards, including HTTP 1.1, HTTP Compression, Secure Sockets Layer,and Common Gateway Interface (CGI), and the new Internet collaboration standard, WebDistributed Authoring and Versioning (WebDAV).

In addition, IIS 5.0 goes further than a simple Web server by providing the environment andservices application developers need to quickly create sophisticated Web-enabled applications.One of the most significant application development technologies included in IIS 5.0 is ActiveServer Pages.An ASP page contains a simple program-a script-written in a powerful scriptinglanguage, such as VBScript, and executed at the server. ASP pages in IIS 5.0 offer developersmany benefits:

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• Greatly improved scalability and reliability With IIS Reliable Restart and other enhance-ments, IIS in Windows 2000 allows developers to build applications that support moreusers and stay running.

• Access to COM+ objects Because an ASP page can create and use COM+ objects, theentire world of component-based applications is accessible to it.

• Integration with COM+-based applications Because ASP is a COM+ application, allCOM+ applications and capabilities are available in ASP.

• Transactional ASP scripts COM+ integration allows creation of ASP pages that aretransactional, meaning that all operations performed by the script can succeed or fail asa unit.

• Process isolation ASP pages can run in the same process as IIS, offering the best perfor-

mance, or in a separate process, offering greater isolation in the event of failures. IIS nowsupports three application protection modes: High Medium and Low, allowing developersto balance overall Web server reliability with application performance.

• Support for standard, well-known languages Because VBScript is a subset of Visual Basic,millions of developers are familiar with VBScript today. ASP pages can also be writtenin JavaScript, another popular and well-supported language.

• Ability to distribute processing load across servers By using Windows Load BalancingService (WLBS), included with Windows 2000 Advanced Server, processor-intensive ASPapplications can be run on multiple machines to support higher numbers of users. New

ASP features in Windows 2000 Server improve performance and make it easier to writeapplications that use IIS 5.0 and ASP. These features include:

• Error handling ASP now has new error handling that lets developers trap errors in acustom error message .asp file. Using the new error method, developers can displayuseful information, such as an error description or the line number in an .asp file wherethe error occurred

• Scriptless ASP ASP pages that don’t contain server-side script are processed as if theywere static HTML pages.

• Flow control Rather than redirecting requests, which requires a performance-impactingroundtrip to the client, Web developers can transfer requests directly to an .asp filewithout ever leaving the server.

• Performance-enhanced objects IIS provides updated performance enhanced versions of popular installable components.

• Self-tuning IIS can determine when executing requests need additional resources andautomatically provide more threads when required.

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5 Design Notations

5.1 Data Flow Diagram

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DFD Level 1

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6 Conclusion

The Mailman system, once in place, is expected to provide a more convenient and reliable servicecompared to traditional mail servers. Status tracking module will help to ensure the delivery of

critical emails and help us make prompt action in case of non-receipt.Security is provided by usingencryption and decryption. It encrypts password and message while sending and in the receivingside it decrypts the message.It also contains another feature, chatting. By using on-line chatting,users can seamlessly communicates by sending and receiving messages.It also includes a feature todelete mails after a particular date. While sending ,senders can specify the destruction date. On thepredefined date the mail is automatically removed from the inbox of the recipient whether it is reador unread.This set of enhancements adds a layer of premium functionality over email communicationthus taking the entire system to next level.

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References

[1] http://www.powermta.port25.com/windows-email server/. March 2002.

[2] http://whatismyipaddress.com/mail server. April 1999.

Documents

Mailman-A Complete Mail Server