This section starts off by taking a look at the Department of Defense’s version of TCP/IP, and then compares it and its protocols with the OSI Reference Model. This section reviews the functions of TCP/IP at the Network layer
IP uses the Department of Defense (DoD) model, which is a condensed version of the OSI model, composed of four instead of seven layers. These layers are:
The Process/Application layer
The Host-to-Host layer
The Internet layer
The Network Access layer
Process/Application-Layer Protocols
This section covers the various protocols, applications, and services typically used in IP networks
Telnet
This protocol’s specialty is terminal emulation.
File Transfer Protocol (FTP)
The protocol that actually lets us transfer files. FTP is a connection oriented service that uses TCP and can provide login and authentication.
Trivial File Transfer Protocol (TFTP)
The stripped-down, stock version of FTP. It uses UDP at the Transport layer and is connectionless.
Network File System (NFS)
Designed by Sun Microsystems to provide a file system that can be shared by disparate systems.
Simple Mail Transfer Protocol (SMTP)
Answering our ubiquitous call to e-mail, SMTP uses a spooled, or queued, method of mail delivery.
Line Printer Daemon (LPD)
Designed for printer sharing.
X Window
Designed for client-server operations, X Window (or just X) defines a protocol for the writing of graphical user interface (GUI) based client/server applications.
Domain Name System (DNS)
Used to resolve hostnames and specifically used to resolve Internet names. DNS is used to resolve fully qualified domain names (FQDNs) for example,
http://www.puggal.com/ or
server1.Puggal.com
Dynamic Host Configuration Protocol (DHCP)
Used to give IP addresses and other network configuration dynamically to hosts.
Internet-Layer Protocols
There are two main reasons for the Internet layer’s existence. First, none of the protocols on layers above or below has any functions relating to routing; this complex and important task is the job of the Internet layer.
Internet Protocol (IP)
Responsible for logical network addressing and routing through an internetwork.
Internet Control Message Protocol (ICMP)
Used to provide a messaging service for IP.
Address Resolution Protocol (ARP)
Used to resolve a known IP address to an Ethernet address.
Reverse Address Resolution Protocol (RARP)
Used to resolve a known Ethernet address to an IP address.
Related posts:
- TCP-IP Network-layer protocol Exam Points
- OSI Network layer Exam Points
- Data link and Network Addresses
- Function of the MAC Address
- MAC Addresses Exams Point
- Full and Half-Duplex Ethernet Operation
- PPP Operations to Encapsulate WAN data on Cisco Routers
- Spanning Tree Protocol
- IGRP Routing Protocol
- Problems that Each Routing type Encounters When Dealing with Topology changes and Techniques to Reduce the Number of Problems
