ppt on computer network

1. By:
Simarpreet kaur

2. Networking Basics
• Switch: It connects multiple computers and mobile devices together into a local
network.It serves as a central point through which computers on that local
network communicate with each other.It cannot connect to other networks by
itself–it requires a router to communicate with other networks.
• Router: A router connects separate networks, allowing information to route from
one to the other. The networks may be physically separate, such as a home office
network and the Internet, or logically separate, such as subnetworks that share
cabling. In this sense, a router forwards data between networks in much the same
way as a postal distribution center forwards mail between cities.
• Firewall: A network firewall is a security device that puts up a barrier between a
local network and the Internet.It acts as a filter, allowing or restricting data traffic
between the network it protects and other networks. They are flexible, allow to
modify the blocking rules, such as by IP address, by protocol

3. DNS(Domain
Name System)
The Domain Name System (DNS) is the phonebook of the
Internet. Humans access information online through domain
names, like nytimes.com or espn.com. Web browsers interact
through Internet Protocol (IP) addresses. DNS translates domain
names to IP addresses so browsers can load Internet resources.
DNS works with the help of DNS servers. When a user enters the
domain name into the web browser, the request goes to the DNS
server. The DNS server determines the IP address using a look-up
table. Then it sends the requested information to user?s web
browser through proper servers.

4. IP Address
An IP address is a unique address that identifies a device on the
internet or a local network. IP stands for "Internet Protocol,"
which is the set of rules governing the format of data sent via the
internet or local network.
It is a string of numbers separated by periods. IP addresses are
expressed as a set of four numbers — an example address might
be 192.158.1.38. Each number in the set can range from 0 to
255. So, the full IP addressing range goes from 0.0.0.0 to
255.255.255.255.

5. TCP(Transmission
Control Protocol)
• TCP is a connection-oriented protocol. Connection-
orientation means that the communicating devices should
establish a connection before transmitting data and should
close the connection after transmitting the data.
• It is reliable as it guarantees the delivery of data to the
destination router.
• Provides extensive error checking mechanisms. It is because
it provides flow control and acknowledgment of data.

6. Establishing a
TCP Connection
The 3-way handshake
• Guarantee that both sides are ready for connection
• Allows both sides to agree on initial sequence
numbers
Site 1 Network Site 2
Send SYN seq=x
Send SYN seq=y,
ACK x+1
Send ACK y+1
Receive SYN&ACK
Receive ACK

7. Closing a TCP
Connection (cont)

8. UDP(User Datagram
Protocol)
• UDP is the Datagram oriented protocol. This is because
there is no overhead for opening a connection,
maintaining a connection, and terminating a
connection.
• The delivery of data to the destination cannot be
guaranteed in UDP.
• It has only the basic error checking mechanism using
checksums.

9. Subnetting
• When a bigger network is divided into smaller
networks, in order to maintain security, then that is
known as Subnetting. so, maintenance is easier for
smaller networks.
• allows to limit the number of routers that network
traffic has to pass through.
• subnet mask echoes an IP address, but it can only be
utilized within an internal network. This mask helps
to identify which part of the IP address relates to the
network and which part relates to the host.

10. Working of
Subnet

11. SNPM Trap
• Simple Network Management Protocol (SNMP) is used by
different devices (Routers, Switches, Printers, etc.) on the
network to check each other’s activity and communicate
critical information.
• SNMP Traps are the most frequently used alert messages sent
from a remote SNMP-enabled device (an agent) to a central
collector, the “SNMP manager.”
• A Trap might report an event of overheating in a machine.
• They are the main form of communication between an SNMP
Agent and SNMP Manager. They are used to inform an SNMP
manager when a significant event occurs at the Agent level.

12. SNPM Trap(cont)

13. MIB
MIB stands for Management Information Base and
is a collection of information organized
hierarchically. These are accessed using a protocol
such as SNMP

14. Network Fault Management
• In order to prevent network downtime and equipment failures -
as well as recover in a timely manner when these events do
happen - it's necessary to have an efficient network fault
management system.
• The ISO Network Management Model lists fault monitoring as
one of the five key functional areas of network
management and defines it as the ability to detect, isolate,
notify, and correct faults encountered in the network.

15. What Role Does Network Fault
Management Play in Companies?
Network fault management refers to the activities, methods,
procedures, and tools that pertain to the operation, administration,
maintenance, and provisioning of your networked systems.
Operation deals with keeping your network (and the services that your
network provides) up and running smoothly. It includes monitoring the
network to spot problems as soon as possible, ideally before users are
affected.
Administration deals with keeping track of your resources in the
network and how they are assigned. It includes all the "housekeeping"
that is necessary to keep your network under control.
Maintenance is concerned with performing repairs and upgrades - for
example, when your equipment must be replaced, when a router needs
a patch for an operating system image, when a new switch is added to a
network.
Provisioning is concerned with configuring resources in your network to
support a given service. For example, this might be setting up your
network so that a new customer can receive voice service.

16. Network Protocols
• HTTP(Hyper text transfer protocol):It is a TCP/IP based
communication protocol, that is used to deliver data
(HTML files, image files, query results, etc.) on the World
Wide Web. It provides a standardized way for computers
to communicate with each other and specifies how clients'
request data will be constructed and sent to the server,
and how the servers respond to these requests.
• TCP(Transmission Control Protocol): It is a transport layer
protocol that facilitates the transmission of packets from
source to destination. It is a connection-oriented protocol
that means it establishes the connection prior to the
communication that occurs between the computing
devices in a network.

17. Network
Protocols(cont)
• SOAP:It is known as the Simple Object Access Protocol.It is an XML-
based protocol for accessing web services over HTTP,it tells how
web services talk to each other or talk to client applications that
invoke them.
• Simple Network Management Protocol (SNMP) :is a standard
protocol used for the communication and management of network
devices connected over an IP. With a set of standards, SNMP
collects data from different hardware and software, organizes
them, and aids in network fault detection and analysis. Most of the
network devices like routers, switches, firewalls, printers, servers,
CCTV cameras, and wireless access points are SNMP-enabled, and
they send the performance data for monitoring.

18. Load Balancer
Load balancing is defined as the methodical and
efficient distribution of network or application
traffic across multiple servers in a server farm. Each
load balancer sits between client devices and
backend servers, receiving and then distributing
incoming requests to any available server capable
of fulfilling them.

19. Virtualization
Virtualization uses software to create an
abstraction layer over computer hardware that
allows the hardware elements of a single
computer—processors, memory, storage and more
to be divided into multiple virtual computers,
commonly called virtual machines (VMs). Each VM
runs its own operating system and behaves like an
independent computer, even though it is running
on just a portion of the actual underlying computer
hardware.

20. Amazon EC2
Amazon Elastic Compute Cloud (Amazon EC2) is a
web service that provides secure, resizable
compute capacity in the cloud. It is designed to
make web-scale cloud computing easier for
developers ,allows to obtain and configure capacity
with minimal friction. It provides you with complete
control of your computing resources and lets you
run on Amazon’s proven computing environment.

21. Azure
At its core, Azure is a public cloud computing
platform—with solutions including Infrastructure as
a Service (IaaS), Platform as a Service (PaaS),
and Software as a Service (SaaS) that can be used
for services such as analytics, virtual computing,
storage, networking, and much more. It can be used
to replace or supplement your on-premise servers.

22. THANK YOU