Slide 1 : Networking Operating Systems (NOSs) :
Popular NOS
Unix.
Microsoft’s Windows NT Server 2000 , 2003, XP and so on.
Linux ES and AS.
Network Resources Access.
Slide 2 : Peer-to-Peer network :
A peer-to-peer network, computers send messages and requests directly to one another without a server intermediary.
Client – Server Resources Model :
Slide 3 : Network Topologies :
Five Main Topologies:
Bus Topology.
Star Topology.
Ring Topology.
Mesh Topology.
Hybrid Topology.
Slide 4 : Bus Topology.
Bus Network, , a topology (configuration) for a local area network in which all nodes are connected to a main communications line (bus). On a bus network, each node monitors activity on the line. Messages are detected by all nodes but are accepted only by the node(s) to which they are addressed. Bus Network:
With this arrangement, even if one of the nodes goes down, the rest of the network can continue to function normally.
Slide 5 : Star Topology :
In a star configuration, computers are linked to a central computer called a hub. A computer sends the address of the receiver and the data to the hub, which then links the sending and receiving computers directly. A star network allows multiple messages to be sent simultaneously, but it is more costly because it uses an additional computer, the hub, to direct the data.
Slide 6 : Ring Network :
In a ring network, messages travel in one direction around a ring from node to node. As each node receives a message, it checks the message address. If the message is not for that particular node, the message is regenerated and passed on. This regeneration allows messages to travel farther in a ring network than in other network configurations.
Slide 7 : Mesh Topology: FORMULA
X * (X-1) / 2
Slide 8 : Hybrid Topology :
Slide 9 : Network Communications :
If two computer are going to communicate, they both must be using the same protocols.
We will discuss Two main type of Protocols :
OSI Model.
IEEE 802 standards.
Slide 10 : OSI MODEL :
On the conceptual level, networking and communications standards such as the OSI Open Systems Interconnection (OSI) model combine hardware and software guidelines to enable entire systems and their associated devices to connect with one another. Although the ISO/OSI model and other guidelines are not literal, physical interfaces, they define ways for different systems to connect and communicate.
There are seven layers that describe OSI Models :
General formula :
Please Do Not Throw Sausages, Pizza Away
Slide 11 : The seven Layers are as under :
Application Layer (L 7)
Presentation Layer (L 6)
Session Layer (L 5)
Transport Layer (L 4)
Network Layer (L 3)
Data Link Layer (L 2)
Physical Layer (L 1)
Slide 12 : NIC : ( Network Interface Card )
Or LAN Card
( IEEE 802 standard )
In hardware, interfaces are cards, plugs, and other devices that connect pieces of hardware with the computer so that information can be moved from place to place.
Slide 13 : The Following factors should be taken into consideration when choosing a NIC :
Preparing data
Sending and Controlling Data
Configuration
Drivers
Compatibility
Performance