TSMG5330-F13-Group 7

The Folks

• TrinadhGanesh Veeravalli
• VishnuVardhan Murughian
• Praveen Chekka
• Vignesh Raja Swaminathan

Motivation

The Linux server project distinguishes and helps to understand the basic difference between knowledge and skill. This project is instrumental in converting the acquired basic knowledge of the protocols and concepts to a practical design which is nothing but the implementation of networking concepts using available resources. An ideal solutions engineer would come up with a design considering the factors of capital, resources required to implement the requirements in the way they want to. This project is the best possible solution, which is robust, secure, dynamic and intelligent enough to cater to the needs of an enterprise.

Understanding the Protocol

DHCP

Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway. RFCs 2131 and 2132 define DHCP as an Internet Engineering Task Force (IETF) standard based on Bootstrap Protocol (BOOTP), a protocol with which DHCP shares many implementation details. DHCP allows hosts to obtain necessary TCP/IP configuration information from a DHCP server. Dynamic addressing simplifies network administration because the software keeps track of IP addresses rather than requiring an administrator to manage the task. This means that a new computer can be added to a network without the hassle of manually assigning it a unique IP address. DHCP also supports a mix of static and dynamic IP addresses. With dynamic addressing, a device can have a different IP address every time it connects to the network. In some systems, the device's IP address can even change while it is still connected.

Use of DHCP:

Every device on a TCP/IP-based network must have a unique unicast IP address to access the network and its resources. Without DHCP, IP addresses must be configured manually for new computers or computers that are moved from one subnet to another, and manually reclaimed for computers that are removed from the network. DHCP enables this entire process to be automated and managed centrally. The DHCP server maintains a pool of IP addresses and leases an address to any DHCP-enabled client when it starts up on the network. Because the IP addresses are dynamic (leased) rather than static (permanently assigned), addresses no longer in use are automatically returned to the pool for reallocation. The network administrator establishes DHCP servers that maintain TCP/IP configuration information and provide address configuration to DHCP-enabled clients in the form of a lease offer.

The DHCP server stores the configuration information in a database, which includes:

Valid TCP/IP configuration parameters for all clients on the network.

Valid IP addresses, maintained in a pool for assignment to clients, as well as excluded addresses.

Reserved IP addresses associated with particular DHCP clients. This allows consistent assignment of a single IP address to a single DHCP client.

The lease duration, or the length of time for which the IP address can be used before a lease renewal is required.

A DHCP-enabled client, upon accepting a lease offer, receives a valid IP address for the subnet to which it is connecting.

DNS

Domain Name System/Service/Server is an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address. For example, the domain name www.tsmg5330grp7.com might translate to 198.105.232.4. The DNS system is, in fact, its own network. If one DNS server doesn't know how to translate a particular domain name, it asks another one, and so on, until the correct IP address is returned.

Use of DNS:

DNS is used everywhere on the Internet, as well as in many private networks. The number of uses for DNS is nearly unlimited, as almost any network service can benefit from it in some way or another. Every page on the World Wide Web accessed by name not by IP address. E-mail uses DNS to get your mail to its destination. The World Wide Web uses DNS extensively. The web is the most visible use of DNS on the Internet though it may lag behind e-mail in popularity. Every time you access a Web site by name, such as www.g7.com, DNS references a host record to resolve that name to an IP address. The Web is actually one of the more simple uses for DNS as once the name is resolved, the web browser retrieves the content from the web server using the address. You can see DNS at work every time you load a page in your browser. E-mail is reported as the most popular use of the Internet based on the total number of users; without DNS, e-mail wouldn't function like it does today. E-mail uses DNS for mail routing; mail routing is used to get an e-mail that you send from your mail server to the recipient's mail server. This is facilitated by the mail exchanger record in DNS. The mail server first inspects the domain in the e-mail address called the host portion of the address; every thing before the @ symbol in an e-mail address is referred to as the user portion. While everything following the @ symbol is called the host portion. It then uses DNS to resolve the mail exchanger record for this domain to an IP address. Finally it uses the SMTP protocol to send the message to the receiving server's IP address resolved in the last step. Unfortunately it's hard to show an example of this process, but it occurs every time an e-mail is sent. Microsoft active directory uses DNS as one of the core building blocks in its infrastructure. DNS is used with active directory to maintain database of services on that network; these services are listed in DNS using service records. Service records allow any client in an active directory environment to locate any service it needs such as a printer. This DNS integration removes the requirement of knowing which server hosts are given a resource. As was the case in versions in Microsoft windows before active directory was released. Instead a client can use resources without knowing anything about the underlying network and server layout. DNS is used for a variety of other applications as well; any time you reference a host by its DNS name, DNS is used. This occurs regardless of the service you're using. Some examples of services that use DNS are telnet and SSH for remote system access to UNIX servers, some database client utilities, groupware clients and back-up utilities. Typically, these applications will reference the target server based on its host record.

Web Server

Web servers are computers that deliver web pages. Every Web server has an IP address and possibly a domain name. For example, if a URL http://www.tsmg5330.com/g7.html in your browser, this sends a request to the Web server whose domain name is tsmg5330.com. The server then fetches the page named g7.html and sends it to the browser. Any computer can be turned into a Web server by installing server software and connecting the machine to the Internet. Every computer on the Internet that contains a Web site must have a Web server program. Two leading Web servers are Apache , the most widely-installed Web server, and Microsoft's Internet Information Server ( IIS ). Other Web servers include Novell's Web Server for users of its NetWare operating system and IBM's family of Lotus Domino servers, primarily for IBM's OS/390 and AS/400 customers.

Web servers often come as part of a larger package of Internet- and intranet-related programs for serving e-mail, downloading requests for File Transfer Protocol ( FTP ) files, and building and publishing Web pages. Considerations in choosing a Web server include how well it works with the operating system and other servers, its ability to handle server-side programming, security characteristics, and publishing, search engine, and site building tools that may come with

How to configure webserver.

Web server can be easily configured with the help of a simple command:

sudo apt-get install apache2

this command downloads and installs the apache server.The latest version of apache server released is 2.4.7.This involves the least number of steps in configuring the server than any other server.Now the Linux machine can be used as a webserver.

Firewall

Firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria. . A firewall is considered a first line of defense in protecting private information. For greater security, data can be encrypted.

There are several types of firewall techniques: 1. Packet filter: Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing.

2. Application gateway: Applies security mechanisms to specific applications, such as FTP and Telnet servers. This is very effective, but can impose a performance degradation.

3. Circuit-level gateway: Applies security mechanisms when a TCP or UDP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.

4. Proxy server: Intercepts all messages entering and leaving the network. The proxy server effectively hides the true network addresses.

Backup Server

A server responsible for backing up and restoring files, folders, databases and hard drives on a network in order to prevent the loss of data in the event of a hard drive failure, user error, disaster or accident. In addition to numerous backup server products and services available from third-party vendors, Microsoft Windows Server operating systems also include a built-in Windows Server Backup feature that can be used to perform basic backup and recovery operations on backup servers. An alternative to standard backup server software tools are online backup and recovery services that save your network's data to a remote location in the cloud.

Architecture Fundamental Logic

The Requirements

What ever you needed to do for the project

Steps to perform the setup / installation

DHCP

A four step process is required:

1. DHCP Discovery message

2. DHCP offer message

3. DHCP request message

4. DHCP ACK message

Testing

Tests Plan

Test Tools

Test Cases

Future Prospects

Expansion

Growth

Improvements

Citations

Websites, Books, Articles

Reference

http://technet.microsoft.com/en-us/library/cc781008(v=ws.10).aspx