2. OSI and TCP/IP are two reference models to
describe the network protocols and the purpose
and functions of various network devices.
Protocols are the set of rules to pack the message on the
source’s side, transmit the packets along the medium, and
unpack the message on the destination’s side.
3. The OSI Model
The OSI Reference Model contains seven layers
that define the functions of data communication
protocols. Each layer of the OSI model represents
a function performed when data are transferred
between cooperating applications across an
intervening network.
4.
5. MAC / IP
The MAC (Media Access Control) and IP (Internet
Protocol) are the two addresses that identify your
computer in a network. An IP is a logical address
that is usually assigned by the network administrator
or Internet service provider. A MAC is a physical
permanent address that is already embedded on the
network card during manufacturing.
6. TCP/IP Model
TCP/IP is responsible for a wide range of activity:
It must interface with hardware, route data to
appropriate places, provide error control, and
much more. The TCP/IP model is divided into
four layers: Network access, Internet,
Transport, and Application
7.
8. Network Topologies
In computer networking, topology refers to the
layout of connected devices. Think of a topology as
a network’s virtual shape or structure.
Network topologies are categorized into the
following basic types: bus, ring, star, tree, mesh.
More complex networks can be built as hybrids of
two or more of the above basic topologies.
9.
10. Bus Topology
Bus networks use a common backbone to
connect all devices. A device demands to
communicate with another device on the network
sends a broadcast message over the wire that all
other devices see, but only the intended recipient
actually accepts and processes the message.
11.
12. Ring Topology
In a ring network, every device has exactly two
neighbors for communication purposes. All
messages travel through a ring in the same
direction (either “clockwise” or
counterclockwise”). A failure in any cable or
device breaks the loop and can take down the
entire network.
13.
14. Star Topology
Many home, school, and office networks use the
star topology. A star network features a central
connection point called a hub that may be a hub or
switch. Devices typically connect to the hub with
unshielded twisted pair (UTP). Compared to the
bus topology, a star network generally requires
more cable, but a failure in any star network cable
will take down only one computer’s network access
and not the entire LAN. (If the hub fails, however,
the entire network also fails.)
15.
16. Tree Topology
Tree topologies integrate multiple star topologies
together into a bus. In its simplest form, only hub
devices connect directly to the tree bus. Each hub
functions as the root of a tree of devices.
17.
18. Mesh Topology
A network setup where each computer and
network device is interconnected with one
another, allowing for most transmissions to be
distributed, even if one of the connections go
down. This topology is not commonly used for
most computer networks as it is difficult and
expensive to have redundant connection to every
computer.
