1. SUBMITTED BY: NAIMISHYA ATRI(7TH SEM) IT BRANCH
NETWORK SERVICES
SUBMITTED BY:
NAIMISHYA ATRI(7TH SEM)
IT BRANCH

2. NETWORK SERVICES
Network services are the foundation of a networked computing environment
Network services are configured on corporate LAN’s to ensure security and user friendly operation
, printing and network file sharing services are also network services

3. NETWORK SERVICES INCLUDE:
Common network services include:
Authentication servers
Directory services
Dynamic Host Configuration Protocol (DHCP)
DNS

4. Authentication Servers
Authentication servers are servers that provide authentication services to users or other systems via networking.
Authentication is used as the basis for authorization , privacy  and non-repudiation .
The major authentication algorithms utilized are passwords, Kerberos, and public key encryption.

5. Directory Services
A directory service is the software system that stores, organizes and provides access to information in a directory.
They may be very narrow in scope, supporting only a small set of node types and data types, or they may be very broad.
In a directory used by a network operating system, the nodes represent resources that are managed by the OS

6. dhcp
The Dynamic Host Configuration Protocol (DHCP) is an auto configuration protocol used on IP networks.
DHCP allows a computer to be configured automatically, eliminating the need for intervention by a network administrator.
It also provides a central database for keeping track of computers that have been connected to the network.
There are two versions of DHCP, one for IPv4 and one for IPv6

7. Electronic mails
is a method of exchanging digital messages across the Internet or other computer networks.
 server computer systems accept, forward, deliver and store messages on behalf of users.
An electronic mail message consists of two components, the message header, and the message body, which is the 's content.
s carry multi-media content attachments.

8. Domain name systems(dns)
It is a distributed hierarchical naming system for computers,services,or any other resource connected to internet or private network.
It translates domain names into numerical identifiers associated with networking equipments.
It also stores information such as, the list of mail servers that accept for a given internet domain.

9. bind Berkeley Internet Name Domain
maintains the DNS-related software suite that runs under Linux
has a security record comparable to other modern Internet software.
BIND itself was re-written in version 9, which has a security record comparable to other modern Internet software.

10. Domain name space

11. Domain name servers
The Domain Name System is maintained by a distributed database system, which uses the client-server model.
The nodes of this database are the name servers.
The top of the hierarchy is served by the root nameservers, the servers to query when looking up (resolving) a top-level domain name (TLD).
There are two types :authoritative name servers & caching only name servers.

12. File transfer protocol
FTP is one of the most popular applications used to copy files between computers via a network connection.
From the remote user's perspective, there are two types of FTP :regular FTP & remote FTP.
The File Transfer Protocol (FTP) is used as one of the most common means of copying files between servers over the Internet.
It operates in two connection channels:
FTP Control Channel, TCP Port 21
FTP Data Channel, TCP Port 20

13. Types of ftp

14. vsftpd It stands for Very Secure FTP Daemon .
It is used in Linux operating system for security.
Passive FTP is present by default in Linux systems.
Vsftpd version for REDHAT is vsftpd_2.0.4

15. How To Get VSFTPD Started
With REDHAT to start, stop, or restart VSFTPD after booting we use these commands:
tmp]# /etc/init.d/vsftpd start
tmp]# /etc/init.d/vsftpd stop
tmp]# /etc/init.d/vsftpd restart
We can configure VSFTPD to start at boot we use the chkconfig command.
tmp]# chkconfig vsftpd on

16. SENDMAIL
Sendmail is a general purpose internetwork routing facility that supports many kinds of mail- transfer and delivery methods.
Sendmail is a well known project of the free and open source software and unix communities.
To handle mails for a domain,DNS with MX record is configured for that domain.

17. Incoming mail & outgoing mail
Incoming Mail : . Users retrieve their mail from the mail server using client software, such as Microsoft's Outlook or Outlook Express, that supports either the POP or IMAP mail retrieval protocols.
Outgoing Mail : . PC and Linux workstation users configure their software to make the mail server their outbound SMTP mail server.

18. INSTALLING SENDMAIL
use the chkconfig command to get sendmail configured to start at boot:
tmp]# chkconfig sendmail on
To start, stop, and restart sendmail after booting, use :
tmp]# service sendmail start
tmp]# service sendmail stop
tmp]# service sendmail restart

19. test Mail Server's Name In DNS
Firstly need to make sure that your mail server’s name resolves in DNS correctly.
Testing can be done by using the host command:
tmp]# host bigboy.my-site.com
bigboy.my-site.com has address
tmp]#

20. Apache servers
Apache is web server software notable for playing a key role in the initial growth of the World Wide Web. 
Apache is primarily used to serve both static content and dynamic Web pages on the World Wide Web.
Apache is used where content needs to be made available in a secure and reliable way.

21. How To Get Apache Started
Use the chkconfig command to configure Apache to start at boot:
tmp]# chkconfig httpd on
Use the httpd<code> init script in the <code>/etc/init.d directory to start,stop, and restart Apache after booting:
tmp]# /etc/init.d/httpd start
tmp]# /etc/init.d/httpd stop
tmp]# /etc/init.d/httpd restart

22. Virtual Hosting
Virtual hosting is a method for hosting multiple domain names on a computer using a single IP address.
Virtual hosting is a method for hosting multiple domain names on a computer using a single IP address.
This allows one machine to share its resources, such as memory and processor cycles, to use its resources more efficiently.

23. Types of Virtual Hosting
Name-based : make your Web server host more than one site per IP address by using Apache’s named virtual hosting features.
IP-based : It consists of one IP address per website. It contains a single <VirtualHost>container per IP address.