User`s guide

144
TCP/IP Network Basics
TCP/IP Protocols
TCP/IP Protocols
This section summarizes protocols for LAN networks that use TCP/IP for
communication between hosts (devices such as computers, printers, and
instruments), including:
! The TCP/IP Network Model
! The Network Interface Layer
! The Internet Layer
! The Transport Layer
! The Application Layer
The TCP/IP Network Model
The TCP/IP network model is based on protocols and an associated set of
layers that control the actions of the network. A
protocol is a rule or set of
rules and standards for communication and data transfer between
hosts on
a network. A
host is any device on the network (such as a computer, server,
printer, etc.) that has a TCP/IP address. To exchange data on the network,
the source and destination hosts must agree on the protocol and each host
must have a unique (TCP/IP) address. When protocols are grouped
together, they form a
protocol suite and work together as a protocol stack.
TCP/IP Layers The TCP/IP network model is based on the Department of Defense (DoD)
model. This figure summarizes the functions of the layers in the model.
Application
Transport
Internet
Network Interface
Application Layer
Contains applications that
process requests from other
hosts on the network.
Transport Layer
Determines if sender and receiver
hosts will set up a connection
(before communicating). Sets
how hosts will acknowledge
connection with each other.
Internet Layer
Responsible for addressing and
routing of packets.
Network Interface Layer
Defines how a host connects to
the network.