CHAPTER 3

UNICAST

A one-to-one delivery option. meaning there is only a single destination for the message.

OSI MODEL

APPLICATION PRESENTATION SESSION TRANSPORT NETWORK DATA LINK PHYSICAL

TCP/IP MODEL

APPLICATION TRANSPORT INTERNET NETWORK ACCESS

Application (OSI MODEL)

CONTAINS PROTOCOLS USED FOR PROCESS-TO-PROCESS COMMUNICATIONS

NETWORK ACCESS

CONTROLS THE HARDWARE DEVICE AND MEDIA THAT MAKE UP THE NETWORK

BITS

DATA (PDU) AT THE PHYSICAL LAYER BEING USED WHEN PHYSICALLY TRANSMITTING DATA OVER THE MEDIUM

PACKET

DATA (PDU) MOVES TO NETWORK LAYER AND BECOMES

FRAME ( MEDIUM DEPENDENT)

DATA (PDU) MOVES TO THE DATA LINK LAYER

TRANSPORT (OSI MODEL)

DEFINES SERVICES TO SEGMENT, TRANSFER,A ND REASSEMBLE THE DATE FOR INDIVIDUAL COMMUNICATIONS BETWEEN END DEVICES

PHYSICAL (OSI MODEL)

DESCRIBE THE MECHANICAL, ELECTRICAL, FUNCTIONAL, AND PROCEDURAL MEANS TO ACTIVATE , MAINTAIN AND DE-ACTIVATE PHYSICAL, PHYSICAL CONNECTIONS FOR BIT TRANSMISSION TO AND FROM A NETWORK DEVICE

DATA LINK (OSI MODEL)

DESCRIBES METHODS FOR EXCHANGING DATA FRAMES BETWEEN DEVICES OVER A COMMON MEDIA

INTERNET (TCP/IP MODEL)

DETERMINES THE BEST PATH THROUGH THE NETWORK

BROADCAST

If all hosts on the network need to receive the message at the same time. represents a one-to-all message delivery option. Additionally, hosts may be required to acknowledge the receipt of some messages while not needing to acknowledge others.

TWO PARTS OF AN IP ADDRESS

NETWORK PORTION HOST PORTION

Role of the Data Link Layer Addresses

On an Ethernet network, the data link addresses are known as Ethernet (Media Access Control) addresses. MAC addresses are physically embedded on the Ethernet NIC.

PRESENTATION (OSI MODEL)

PROVIDES FOR COMMON REPRESENTATION OF THE DATA TRANSFERRED BETWEEN APPLICATION LAYER SERVICES

NETWORK (OSI MODEL)

PROVIDES SERVICES TO EXCHANGE THE INDIVIDUAL PIECES OF DATA OVER THE NETWORK BETWEEN IDENTIFIED END DEVICES

SESSION (OSI MODEL)

PROVIDES SERVICES TO THE PRESENTATION LAYER TO ORGANIZE ITS DIALOGUE AND TO MANAGE DATE EXCHANGE

APPLICATION (TCP/IP MODEL)

REPRESENTS DATA TO THE USER, PLUS ENCODING AND DIALOG CONTROL

Network layer source and destination addresses

Responsible for delivering the IP packet from the original source to the final destination, either on the same network or to a remote network

Data link layer source and destination addresses

Responsible for delivering the data link frame from one network interface card (NIC) to another NIC on the same network

TRANSPORT (TCP/IP MODEL)

SUPPORTS COMMUNICATION BETWEEN VARIOUS DEVICES ACROSS DIVERSE NETWORKS

DATA

THE GENERAL TERM USED FOR THE PDU AT THE APPLICATION LAYER

Destination IP address

The IP address of the receiving device, the final destination of the packet.

Source IP address

The IP address of the sending device, the original source of the packet.

protocol data unit (PDU).

The form that a piece of data takes at any layer

NETWORK PORTION

The left-most part of the address that indicates which network the IP address is a member. All devices on the same network will have the same network portion of the address

Destination data link address

The physical address of the NIC that is receiving the data link frame. This address is either the next hop router or of the final destination device.

Source data link address

The physical address of the device's NIC that is sending the data link frame

encapsulation

The process of placing one message format inside another message format .

HOST PORTION

The remaining part of the address that identifies a specific device on the network. The host portion is unique for each device on the network.

SEGMENT

WHEN "DATA" (PDU) IS IN THE TRANSPORT LAYER

MULTICASTING

When a host needs to send messages using a one-to-many delivery option. the delivery of the same message to a group of host destinations simultaneously.

HTTP

an application protocol that governs the way a web server and a web client interact. defines the content and formatting of the requests and responses that are exchanged between the client and server.( APPLICATION LAYER)

Ethernet

is a network access protocol that describes two primary functions: communication over a data link and the physical transmission of data on the network media. Network access protocols are responsible for taking the packets from IP and formatting them to be transmitted over the media. ( NETWORK ACCESS LAYER)

TCP

is the transport protocol that manages the individual conversations. divides the HTTP messages into smaller pieces, called segments. These segments are sent between the web server and client processes running at the destination host.also responsible for controlling the size and rate at which messages are exchanged between the server and the client.( TRANSPORT LAYER)

IP

responsible for taking the formatted segments from TCP, encapsulating them into packets, assigning them the appropriate addresses, and delivering them to the destination host ( INTERNET LAYER)

Decoding

reverses this process in order to interpret the information.

De-encapsulation

the process is reversed by the recipient and the letter is removed from the envelop

Encoding

the process of converting information into another acceptable form, for transmission.