TCP/IP model is base on standard protocols which was developed by Department of Defense (DoD) in 1960s. It contains 4 layers, unlike 7 layers in the OSI model. The four layers are:
- Process/Application Layer
- Host-to-Host/Transport Layer
- Internet Layer
- Network Access/Link Layer
TCP/ IP is the protocol suite use for communication between hosts in most local computers and internet.
TCP/IP is supported and include in may OS i.e Window 7, Xp, Vista, MAC OS, LINIUX AND UNIX.
TCP/IP protocol suite developed before OSI model.
A list of some protocols is explain below,
1. TCP (Transfer Control Protocol)
Transport layer use TCP or UDP protocol for data transmission.
This protocol is connection oriented and provides the reliability to data transfer. Sender cannot send the data until the connection is establish between sender and receiver.TCP divide data into small packets called segments.
Features of TCP
- Connection opening
- Flow control
- Error deduction (by check sum method)
- Connection closing
2. UDP (User Datagram Protocol)
This protocol is not a connection oriented and provides not provide higher reliability to data transfer. Sender can send the data without establishing a connection between sender and receiver. To transfer data UDP provides the following functionality on data.
- Source port address
- Destination port address
- Total length of data in bytes
- Checksum (16 bit error detection)
It provides only the basic functionality of end-to-end delivery of data. It does not provide the sequence number to segments that way it cannot re-order the packets at receiving end.
3. DHCP (Dynamic Host Configuration Protocol)
- It is a protocol use to dynamically assign an IP address to any node, or device on a network.
- The servers that assign and manage the dynamic IP addresses, called DHCP servers.
- The work stations that are dynamically assigned IP addresses by DHCP servers are called DHCP clients.
- DHCP software’s resides on clients and servers to manage the dynamic assignment of IP address.
- Range of IP addresses to be assigned to the clients is specified when DHCP servers are configured.
- DHCP servers assigned IP addresses to DHCP clients from assignable list.
- DHCP servers can assign IP addresses in three different ways.
Automatic Allocation: Server always attempts to assign the same IP address to a given host or node i.e. mail server because other hosts may have saved its internal address.
Dynamic Allocation: Each time the clients log onto the network, Dynamically an IP address is assign to it from available list of IP addresses.
Manual Allocation: A network administrator assigns address to a particular host or node.
4. DNS (Domain Name System)
This protocol is use in presentation layer. IP address is difficult to remember for user. The domain names are alphabetic and are easier to remember. Domain name server resolves this issue.
- We just use the name of website i.e. Facebook, YouTube etc. and DNS finds out their relevant IP address.
- For example domain name www.example .com may translate to 126.96.36.199
- Domain name server must updated periodically to include new domain names.
5. SMTP (Simple Mail Transfer protocol)
SMPT provides the facilities for mail exchange between users on same or different computers. It supports the following
- For Sending a message to one or more computers
- Sending messages that include text, voice, video or graphics
- Sending messages to users on networks outside the internet.
- Firewall is a set of components use to restrict the access to data and information’s on the network.
- It may consist of hardware and software.
- Firewalls are use to restrict the unauthorized users from accessing the resources of an organization.
- Packets are blocked if they are sending from unauthorized users.
- The major kinds of firewalls includes include packet filtering and proxy firewalls.
Some other protocols are given below
- HTTP (hypertext transfer protocol): All webpages from internet accessed through http protocol.
- FTP: to send files on remote server