1. Addis ababa medical and business college
Department of information technology ITNS
Level III
unit of competence install and manage network protocols
Email:- jaletosunkemo2019@gmail.com
2. At the end of this module the trianee will able to know:-
• basic concept of protocol
• network protocol and their function
• how protocol is work
• protocols and port number
• purpose of network protocol
• HTTP,HTTPS,FTP,IP,ICMP,POP3 and etc
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LO1 INTRODUCTION TO NETWORK PROTOCOL
3. basic concept of network protocol
• A network protocol is an established set of
rules that determine how data is
transmitted between different devices in the
same network.
• Essentially, it allows connected devices to
communicate with each other, regardless of
any differences in their internal processes,
structure or design.
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LO1 INTRODUCTION TO NETWORK PROTOCOL
4. CONT...
• a protocol is a standardized set of rules for formatting and
processing data. Protocols enable computers to communicate
with one another.
• Network protocols are a set of rules, conventions, and data
structures that dictate how devices exchange data across
networks.
• Network Protocols are a set of rules governing exchange of
information in an easy, reliable and secure way.
• In order for two computers to talk to each other, they must be
speaking the same language.
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5. List of Network Protocols
• There are thousands of different network
protocols, but they all perform one of three
primary actions:
– Communication
– Network Management
– Security
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6. Communication
• Communication protocols allow different network devices to communicate with
each other. They are used in both analog and digital communications and can be
used for important processes, ranging from transferring files between devices to
accessing the internet.
• Common types of communication protocols include the following:
• Automation: These protocols are used to automate different processes in both
commercial and personal settings, such as in smart buildings, cloud technology or
self-driving vehicles.
• Instant messaging: Instantaneous, text-based communications on smartphones and
computers occur because of a number of different instant messaging network
protocols.
• Routing: Routing protocols permit communication between routers and other
network devices. There are also routing protocols specifically for ad hoc networks.
• Bluetooth: Ever-popular Bluetooth devices — including headsets, smartphones and
computers — work due to a variety of different Bluetooth protocols.
• File transfer: If you have ever moved files from one device to another, either via a
physical or digital medium, you’ve used file transfer protocols (FTP).
• Internet Protocol: Internet Protocol (IP) allows data to be sent between devices via
the internet. The internet could not operate as it currently does without IP.
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7. Network management
• protocols define and describe the various procedures needed to effectively
operate a computer network. These protocols affect various devices on a
single network — including computers, routers and servers — to ensure
each one, and the network as a whole, perform optimally.
• The functions of network management protocols include the following:
• Connection: These protocols establish and maintain stable connections
between different devices on the same network.
• Link aggregation: Link aggregation protocols allow you to combine
multiple network connections into one link between two devices. This
works to increase the strength of the connection and helps sustain the
connection should one of the links fail.
• Troubleshooting: Troubleshooting protocols allow network administrators
to identify errors affecting the network, evaluate the quality of the network
connection, and determine how administrators can fix any issues.
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8. Security
• Security protocols, also called cryptographic protocols, work to
ensure that the network and the data sent over it are protected from
unauthorized users.
• Common functions of security network protocols include the
following:
• Encryption: Encryption protocols protect data and secure areas by
requiring users to input a secret key or password in order to access
that information.
• Entity Authentication: Entity authentication protocols create a
system that requires different devices or users on a network to verify
their identity before accessing secure areas.
• Transportation: Transportation security protocols protect data
while it is transported from one network device to another.
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9. Here are a few examples of the most commonly used network
protocols:
• Hypertext Transfer Protocol (HTTP): This Internet Protocol
defines how data is transmitted over the internet and
determines how web servers and browsers should respond to
commands. This protocol (or its secure counterpart, HTTPS)
appears at the beginning of various URLs or web addresses
online.
• Secure Socket Shell (SSH): This protocol provides secure
access to a computer, even if it’s on an unsecured network.
SSH is particularly useful for network administrators who
need to manage different systems remotely.
• Short Message Service (SMS): This communications
protocol was created to send and receive text messages over
cellular networks. SMS refers exclusively to text-based
messages. Pictures, videos or other media require Multimedia
Messaging Service (MMS), an extension of the SMS protocol.
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10. Cont…
• Protocols
• Protocols are a fundamental aspect of digital
communication as they dictate how to format, transmit
and receive data. They are a set of rules that determines
how the data will be transmitted over the network.
• It can also be defined as a communication standard
followed by the two key parties(sender and receiver) in
a computer network to communicate with each other.
• It specifies what type of data can be transmitted, what
commands are used to send and receive data, and how
data transfers are confirmed.
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11. How to implement network protocols
• In order for network protocols to work, they must be coded within
software -- either as part of the computer's operating system (OS) or
as an application -- or implemented within the computer's hardware.
Most modern OSes possess built-in software services that are
prepared to implement some network protocols. Other applications,
such as web browsers, are designed with software libraries that
support the protocols necessary for the application to function. In
addition, TCP/IP and routing protocol support is implemented in
direct hardware for enhanced performance.
• Whenever a new protocol is implemented, it is added to the protocol
suite. The organization of protocol suites is considered to be
monolithic since all protocols are stored in the same address and
build on top of one another.
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12. Levels of a Protocol
• There are mainly three levels of a protocol, they are as
follows:
• Hardware Level: In this level, the protocol enables the
hardware devices to connect and communicate with
each other for various purposes.
• Software Level: In the software level, the protocol
enables different software to connect and communicate
with each other to work collaboratively.
• Application Level: In this level, the protocol enables
the application programs to connect and communicate
with each other for various purposes.
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13. Types of Protocols
• Protocols can be broadly divided into the
following two types:
– Standard Protocols
– Proprietary Protocols
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14. Standard Protocols
• A standard protocol is a mandated protocol for all
devices. It supports multiple devices and acts as a
standard.
• Standard protocols are not vendor-specific i.e.
they are not specific to a particular company or
organization. They are developed by a group of
experts from different organizations .
• These protocols are publicly available, and we
need not pay for them.
• Some of the examples of Standard Protocols
are FTP, DNS, DHCP, SMTP, TELNET, TFTP, etc.
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15. Proprietary Protocols
• Proprietary protocols are developed by an
individual organization for their specific
devices. We have to take permission from the
organization if we want to use their protocols.
• It is not a standard protocol and it supports
only specific devices. We may have to pay for
these protocols.
• Some of the examples of Proprietary Protocols
are IMessage, Apple Talk, etc.
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16. Key Elements of protocols
• The key elements of the protocol determine
what to be communicated, how it is
communicated, and when it is communicated.
• There are mainly three key elements of a
protocol, they are as follows:
– Syntax
– Semantics
– Timing
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17. Syntax
• Syntax refers to the structure or format of data and
signal levels. It indicates how to read the data in the
form of bits or fields. It also decides the order in which
the data is presented to the receiver.
• Example: A protocol might expect that the size of a
data packet will be 16 bits. In which, the first 4 bits are
the sender’s address, the next 4 bits are the receiver’s
address, the next 4 bits are the check-sum bits, and the
last 4 bits will contain the message. So, every
communication that is following that protocol should
send 16-bit data.
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18. Semantics
• Semantics refers to the interpretation or meaning
of each section of bits or fields. It specifies which
field defines what action. It defines how a
particular section of bits or pattern can be
interpreted, and what action needs to be taken. It
includes control information for coordination and
error handling.
• Example: It interprets whether the bits of address
identify the route to be taken or the final
destination of the message or something else.
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19. Timing
• Timing refers to two characteristics:
– when the data should be sent?
– what will be the speed of sending and receiving the data?
• It performs speed matching, sequencing and flow
control of the data items.
• Example: A sender can send the data at a speed of 100
Mbps, but the receiver can consume it only at a speed
of 20 Mbps, then there may be data losses or the
packets might get dropped. So, proper synchronization
must be there between a sender and a receiver.
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20. Functions of protocols
• The Following are the main functionalities of a
protocol:
• Data Sequencing: It mainly refers to dive data into
packets i.e. it divided the whole data into some packets.
• Data Flow: It mainly deals with sending data to the
correct destination i.e. the flow of the data is correct or
not.
• Data Routing: It refers to select the best path for data
transmission between a sender and a receiver because
there can be many routes from sender to receiver and
you should select the best possible route.
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21. Cont…
• Encapsulation: It refers to the process of taking one
protocol and transferring it to some other another
protocol.
• Segmentation & Reassembly: It deals with
segmenting the data message i.e. diving the data into
packets when data flows from the upper protocol layer
to lower, and reassembly is vice-versa of segmentation
i.e. all the segmented packets are recollected in the
correct order at the receiver side.
• Connection Control: It ensures connection oriented
data transfer for lengthy data items.
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22. cont...
• Multiplexing: It allows combining multiple transmission unit
signals or channels of higher-level protocols in one transmission unit
of a lower-level protocol. Multiplexing can be upward or downward.
• Ordered Delivery: Protocol facilitates ordered delivery of data, by
providing a unique sequence number to each data packet. It is the
function of the sender to maintain ordered delivery. By doing so, the
receiver will receive the data in the same order as sent by the sender.
• Transmission Services: It mainly deals with priority, Quality of
Service (QoS), and security of data packets.
• Addressing: It mainly deals with addressing levels, addressing
scope, communication identifiers, and addressing modes.
• Flow Control: It facilitates to limit the flow of data. It is the
function of the receiver's end to maintain flow control of data.
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23. cont...
• Error Control: It deals with error
detection (using the checksum bits) and
its control. If any error is detected during
the transmission of the data, a request for
retransmission of data is sent to the
sender by the receiver, and the corrupt
data packet is discarded.
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24. There are various types of protocols that support a major and compassionate
role in communicating with different devices across the network. These are:
• Transmission Control Protocol (TCP)
• Internet Protocol (IP)
• User Datagram Protocol (UDP)
• Post office Protocol (POP)
• Simple mail transport Protocol (SMTP)
• File Transfer Protocol (FTP)
• Hyper Text Transfer Protocol (HTTP)
• Hyper Text Transfer Protocol Secure (HTTPS)
• Telnet
• Gopher
• NAT
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25. Cont…
• Transmission Control Protocol (TCP): TCP is a popular
communication protocol which is used for communicating
over a network. It divides any message into series of packets
that are sent from source to destination and there it gets
reassembled at the destination.
• Internet Protocol (IP): An IP is an internet protocol address.
Essentially, it is a numeric value assigned to a network device,
and it is used for the identification and location of a network
device. IP addresses are assigned to every type of network
device.
• IP is designed explicitly as addressing protocol. It is mostly
used with TCP. The IP addresses in packets help in routing
them through different nodes in a network until it reaches the
destination system.
• TCP/IP is the most popular protocol connecting the networks.
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26. Cont..
• User Datagram Protocol (UDP): UDP is a substitute
communication protocol to Transmission Control
Protocol implemented primarily for creating loss-
tolerating and low-latency linking between different
applications.
• Post office Protocol (POP): POP3 is designed for
receiving incoming E-mails.
• Simple mail transport Protocol (SMTP): SMTP is
designed to send and distribute outgoing E-Mail.
• File Transfer Protocol (FTP): FTP allows users to
transfer files from one machine to another. Types of
files may include program files, multimedia files, text
files, and documents, etc.
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27. Cont…
• Hyper Text Transfer Protocol (HTTP): HTTP is designed for transferring a
hypertext among two or more systems. HTML tags are used for creating links.
These links may be in any form like text or images.
– HTTP is designed on Client-server principles which allow a client system for
establishing a connection with the server machine for making a request.
– The server acknowledges the request initiated by the client and responds
accordingly.
• Hyper Text Transfer Protocol Secure (HTTPS): HTTPS is abbreviated as
Hyper Text Transfer Protocol Secure is a standard protocol to secure the
communication among two computers one using the browser and other fetching
data from web server.
– HTTP is used for transferring data between the client browser (request) and the web
server (response) in the hypertext format, same in case of HTTPS except that the
transferring of data is done in an encrypted format.
– So it can be said that https thwart hackers from interpretation or modification of
data throughout the transfer of packets.
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28. Cont…
• Telnet: Telnet is a set of rules designed for
connecting one system with another. The
connecting process here is termed as remote
login.
– The system which requests for connection is the local
computer, and the system which accepts the
connection is the remote computer.
• Gopher: Gopher is a collection of rules
implemented for searching, retrieving as well as
displaying documents from isolated sites.
– Gopher also works on the client/server principle.
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29. cont...
• NAT (network adress translation)is a
method that enables hosts on private networks
to communicate with hosts on the Internet
• NAT is run on routers that connect private
networks to the public Internet, to replace the
IP address-port pair of an IP packet with
another IP address-port pair.
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30. Cont…
• some other popular protocols act as co-functioning protocols
associated with these primary protocols for core functioning.
These are:
• ARP (Address Resolution Protocol)
• DHCP (Dynamic Host Configuration Protocol)
• IMAP4 (Internet Message Access Protocol)
• SIP (Session Initiation Protocol)
• RTP (Real-Time Transport Protocol)
• RLP (Resource Location Protocol)
• RAP (Route Access Protocol)
• L2TP (Layer Two Tunneling Protocol)
• PPTP (Point To Point Tunneling Protocol)
• SNMP (Simple Network Management Protocol)
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31. cont...
• ARP (Address Resolution Protocol)
– is a procedure for mapping a dynamic IP address to a permanent physical
machine address in a local area network (LAN). Or IP into MAC
• (RARP) Reverse Address Resolution Protocol is a protocol a
physical machine in a local area network (LAN) can use to request
its IP address.
– It does this by sending the device's physical address to a specialized RARP
server that is on the same LAN and is actively listening for RARP requests.
• DHCP (Dynamic Host Configuration Protocol)
– dynamic Host Configuration Protocol (DHCP) is a client/server protocol
that automatically provides an Internet Protocol (IP) host with its IP
address and other related configuration information such as the subnet
mask and default gateway.
• NetBIOS (Network Basic Input/Output System) is a network
service that enables applications on different computers to
communicate with each other
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32. Cont..
• IRC (Internet Relay Chat) is a protocol
for real-time text messaging between internet-
connected computers created in 1988.
• It is mainly used for group discussion in chat
rooms called “channels” although it supports
private messages between two users, data
transfer, and various server-side and client-side
commands.
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33. Border Gateway Protocol (BGP)
• BGP:- version 4 is widely used on the public internet
and by Internet Service Providers (ISP) to maintain
very large routing tables and traffic processing. BGP
is one of the few protocols that have been designed to
deal with the astronomically large routing tables that
must exist on the public Internet.
• User Datagram Protocol (UDP) is a Transport Layer
protocol. UDP is a part of the Internet Protocol suite,
referred to as UDP/IP suite. Unlike TCP, it is
an unreliable and connectionless protocol.
• RDP:-
– It enables you to establish a connection with a remote
computer.
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34. SSL
• The Secure Sockets Layer (SSL) protocol was
developed by Netscape Communications
Corporation.
• SSL ensures the data that is transferred
between a client and a server remains private.
This protocol enables the client to authenticate
the identity of the server
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35. What is protocol port
• A port in networking is a software-defined
number associated to a network protocol that
receives or transmits communication for a
specific service.
• A port in computer hardware is a jack or
socket that peripheral hardware plugs into
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36. Some protocols within their ports
Protocol service name Port
numbers
File Transfer Protocol (FTP 20 and 21
Secure Shell (SSH) 22
Telnet 23
Simple Mail Transfer Protocol
(SMTP)
25
Domain Name System (DNS) 53
Trivial File Transfer Protocol
(TFTP)
69
Dynamic Host Configuration
Protocol (DHCP)
67 and 68
IRC 194
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37. cont...
Protocol service name Port numbers
HTTPS 443
POP3 110
Network Time Protocol (NTP) 123
NetBIOS 137/138/139
Internet Message Access Protocol
(IMAP)
143
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