3. INTRODUCTION
The Internet Protocol Suite (commonly known as
TCP/IP) is the set of communications protocols used
for the Internet and other similar networks.
It is named from two of the most important protocols in it:
1. The Transmission Control Protocol (TCP)
2. The Internet Protocol (IP), which were the first two
networking protocols defined in this standard.
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4. What is TCP/IP
• IP addresses are not the same as the underlying
data-link (MAC) addresses.
• IP is a network layer - it must be capable of
providing communication between hosts on
different kinds of networks (different data-link
implementations).
• The address must include information about
what network the receiving host is on.
• This is what makes routing feasible.
IP
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5. IP
• IP Addresses are usually shown in dotted
decimal notation:
1.2.3.4
00000001 00000010 00000011 00000100
• cse.unr.edu is 134.197.40.3
10000110 11000101 00101000 00000010
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6. TCP
• Reliable, full-duplex, connection-oriented,
stream delivery
– Interface presented to the application doesn’t
require data in individual packets
– Data is guaranteed to arrive, and in the correct
order without duplications
• Or the connection will be dropped
– Imposes significant overheads
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7. Applications Of TCP
• Most things!
– HTTP, FTP, …
• Saves the application a lot of work, so
used unless there’s a good reason not to
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8. Addressing in TCP/IP
• Each TCP/IP address includes:
– Internet Address
– Protocol (UDP or TCP)
– Port Number
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9. TCP/IP Network Model
• Different view – 4 layers
– Layer 1 : Application
– Layer 2 : Transport
– Layer 3 : Internet
– Layer 4 : Network
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10. Application
• This layer is comparable to the application,
presentation, and session layers of the
OSI model all combined into one.
It provides a way for applications to have
access to networked services.
• This layer also contains the high level
protocols. The main issue with this layer is
the ability to use both TCP and
• UDP protocols.
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11. •For example TFTP uses UDP because
usually on a LAN the physical links are short
enough to ensure quick and reliable packet
delivery without many errors. SMTP instead
uses TCP because of the error checking
capabilities.
•Since we consider our email important
information we would like to ensure a safe
delivery.
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12. • UDP (User Datagram Protocol) - offering
a direct way to send and receive
datagram over an IP network with very
few error recovery services.
• TFTP (Trivial File Transfer Protocol) -
Simplified version of the FTP protocol
which has no security features.
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13. Application Layer (AL)
• Application Layer (AL), contains those protocols which provides
services to users.
• Web browsing, e-mail, encryption, session establishment all these
things happen in application Layer which uses protocols such as,
• HTTP, SMTP, DNS, TELNET, FTP, NFS, DFS, IMAP4, POP3, NNTP,
• SSH, SSL, GOPHER.
• Application Layer (AL), defines network application services like
file transfer, network management.
• Identification of services is done using port numbers. Ports are
nothing but socket i.e. entry & exit point to the layer.
• Application layer, Presentation layer, Session layer of OSI model
• Responsible for converting data into standard format ex:
ASCII, JPEG, MIDI, MP3.
• Encoding-decoding, encryption-decryption, compression, NFS, RPC
• (remote procedure code).
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14. TRANSPORT
• This layer acts as the delivery service
used by the application layer.
• Again the two protocols used are TCP
and UDP.
• The choice is made based on the
application's transmission reliability
requirements.
• The transport layer also handles all error
detection and recovery.
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15. • It uses checksums, acknowledgements,
and timeouts to control transmissions and
end to end verification.
• Unlike the OSI model, TCP/IP treats
reliability as an end-to-end problem
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16. Transport Layer (TL)
• Two important protocols are used in Transport layer
(TL). They are TCP and UDP
• Transport layer (TL), deals with actual manipulation of
data and prepares it for delivery through network.
• If data is too large for the single frame, then TL
breaks it into smaller pieces and assigns sequence
number.
• It ensures that all the data is received in the right order
than it was sent.
• TL is responsible for ensuring data is sent and
received successfully.
• TL is responsible for verifying delivery of packets.
• Identification services, sequencing, flow control, error
correction,
• segmentation, reassembling is done here.
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17. • A set of interconnected networks
• The Internet is the most famous example
• Networks can be completely different
– Ethernet, ATM, modem, …
– (TCP/)IP is what links them
• Routers (nodes) are devices on multiple
networks that pass traffic between them
• Individual networks pass traffic from one
router or endpoint to another
• TCP/IP hides the details as much as possible
INTERNET
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18. • This layer is also known as Internet layer. The
main purpose of this layer is to organize or
handle the movement of data on network.
• By movement of data, we generally mean
routing of data over the network. The main
protocol used at this layer is IP. While
ICMP(used by popular ‘ping’ command) and
IGMP are also used at this layer.
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19. Internet Layer (IL)
• Internet layer (IL), deals with, finding the way to the destination.
• internet layer (IL) defines, IP addressing, routing, switching.
• It determines where the data should go on the physical network.
• It is responsible for routing each packet to its destination.
• Defines network address.
• Protocols that are used in this layer are routing protocol-OSPF,
RIP, IGRP, EIGRP Routed protocols-IP, IPX, Appletalk. And DDP
(datagram delivery protocol), ICMP, IPSec.
• This layer is also known as network layer in OSI model.
• IL provides best path to the data to reach destination.
• Device working in this layer is Router.
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20. NETWORK
This layer is also known as network
interface layer
This layer normally consists of device drivers
in the OS and the network interface card
attached to the system.
Both the device drivers and the network
interface card take care of the
communication details with the media being
used to transfer the data over the network.
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21. In most of the cases, this media is in the
form of cables.
Some of the famous protocols that are used
at this layer include ARP(Address resolution
protocol), PPP(Point to point protocol) etc.
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22. Network Access Layer
• It is responsible for putting frames (packets) on the wire.
• Responsible for setting bits & bytes, electrical signals and
impulses back and forth across the wire (coaxial or twisted pair).
• Deals with wire, connectors, signals, pulses, modems, fiber optic
cable (in for of light).
• “Doors between worlds” connecting physical aspect of network
(cables & Digital pulses).
• Describes specifications for topology.
• Devices used here are- HUB, Switch, Repeater, Bridges, and NIC.
• MAC – it talks about physical address
• LLC – it talks about wan protocols like ppp, hdlc, and frame relay.
• Responsible for error detection.
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23. Advantages
• It can be used to establish/set up connection
b/w different types of computers.
• It operates/works independently of the
operating system.
• It support for a number of routing-protocols.
• It enables the internetworking between the
organizations.
• It has a scalable, client-server architecture.
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24. Disadvantages
• It is complex to set up & manage.
• IPX is faster than TCP/IP model.
• The shallow/overhead of TCP/IP is higher-than
ipx.
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