THIRD MEETING OF IT2

  OSI MODEL-use for solving problems or tracing problems


OSI-OPEN SYSTEM INTERCINNEC

THE OSI REFERENCE MODEL

• 7 APPLICATION
• 6 PRESENTATION
• 5 SESSION
• 4 TRANSPORT
• 3 NETWORK
• 2 DATA-LINK
• 1 PHYSICAL

APPLICATION- layer deal with networking application
                           Ex: email, web browser
PRESENTATION- responsible for presenting the data in the requered format which may include
SESSION- establishes, manages and termates sessions between communicating hosts
TRANSPORT- breaks up the data from sending host and then ressembles it in the receiver
NETWORK- sometimes referred to as the "cisco layer"
DATA LINK-provides reliable transit of data across a physical link
PHYSICAL- media though which the data

SECOND MEETING OF IT2

 NETWORK INTERFACE CARD (NIC)-
     -is a printed circuit board provides network communication

• HOST- end user devices
• HUB-connects a group of HOST
• SWITCH-switches add more intelligence to data transfer management.
• ROUTER-are used to connect networks together

TOPOLOGY- called by network
LAN- lucal area network

NETWORK TOPOLOGIES

•  network topology-defines the structure of the network
•  logical topology- defines how the media is accessed by the hosts for sending data
• bus topology- user a single backbone cable that is terminated at both ends
• ring topology- connects one host to the next and the last host to the first
• star topology- connects all cables to a central point of concentration
• extended star topology- links individual stars toge ther by connecting the hubs or switches
• mesh topology- implemented to provide as much protection as possible from interraption of sevice

First meeting of IT2

NETWORK MANAGEMENT

ICON

• ATM SWITCH
• ROUTER 
• SWITCH
• COMM SERVER
• ISCN SWITCH
• BRIDGE
• PC
• LAPTOP
• PHONES
• FILE SERVER
• HUB
• MODEM
• PHONE COSTOMER
• NETWORK CLOUD
• BUILDING
• HOME OFFICE

Data Networks 

-sharing data through the use of floppy disks is not efficient or cost effective manner 

-business needed a solution that would succesfully address the ff. three problems.

NETWORK DEVICE-  equipment that connects directly to a network segment is referred to a device