The assignment well defines all the terms I have mentioned in the title. Must give it a read and a like only if you personally like it!

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DATA COMMUNICATION
& NETWORKING
Assignment Submitted To:
Miss Anila
Assignment Submitted By:
Shefa Idrees (101631049)
Assignment Submission Date:
03-01-2019
Post Graduate College for Women, Samnabad Lahore

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What is IPv6?
IPv6 also known as IPng (Internetworking Protocol, next generation) is the replacement
Internet Protocol for IPv4. It corrects some of the deficiencies of IPv4 being better in terms of
complexity and efficiency. It simplifies the way that addresses are configured and how they
are handled by Internet hosts.
Why is IPv6 Needed Now?
The Internet Protocol version 4 is being used in the current internet. The internet protocol
version 6 has been designed for the future needs of the internet. IPv6 is a numerical label that
has following new features to make the network ready for next generation of the internet:
 Large Address Space: Unlike the 32-bit format of IPv4, IPv6 address is 128 bits long
and can support 3.4 x 1038 unique IP addresses.
 BetterHeader Format: Ipv6 header has a separate “options” field. This speeds-up the
routing as most of the times, options are not needed.
 New Options: Several new options have been added to set of options.
 Flow Label Field: To accommodate the real time traffic, the Ipv6 uses Flow Label
field instead of Type of Service field of Ipv4. With this field, a user can request for the
type of service to be given to the datagram.
 Support for More Security: The Ipv6 contains options for encryption and decryption
of data. This provides additional security to the information.
 Allowance for Extension: IPv6 allows the extension of protocol if required.
What is the IPv6 Packet and Header Format?
Packet Format
Internet Protocolversion6 (IPv6)

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Base Header
The eigth fields of Base Header are:
Version: Defines the version of IP that is 6.
Priority: Defines the priority of the packet with respect to traffic congestion.
Flow Label: A 3-byte field to provide special handling for a particular flow of data.
Payload Length: Defines the length of IP datagram excluding the datagram.
Next Header: Defines the header. It is either one of the optional extension headers used by IP
or the header of an encapsulated packet. The Next Header codes for IPv6 are:
Hop Limit: Serves the same purpose as TTL in IPv4 packets.
Source Address: A 16-byte international address that identifies the original source of the
datagram.
Destination Address: A 16-byte internet address to mostly identify the final destination of the
datagram. With source routing, it contains the address of the next router.

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IPv6 Address Representation
The address is divided into eight sections of 16 bits in length. Each 16-bit section is represented
by four hexadecimal digits. A colon is used to separate every four hexadecimal digits. This
way, the address consists of 32 hexadecimal digits.
 Example:
2031:0000:130f:0000:0000:09c0:876a:130b
In IPv6 representation, we have three addressing methods :
 Unicast
 Multicast
 Anycast
Unicast Address: Unicast Address identifies a single network interface. A packet sent to
unicast address is delivered to the interface identified by that address.
Multicast Address: Multicast Address is used by multiple hosts, called as Group, acquires a
multicast destination address. These hosts need not be geographically together. If any packet
is sent to this multicast address, it will be distributed to all interfaces corresponding to that
multicast address.
Anycast Address: Anycast Address is assigned to a group of interfaces. Any packet sent to
anycast address will be delivered to only one member interface (mostly nearest host
possible).
Note : Broadcast is not defined in IPv6, In IPv6, all 0’s and all 1’s can be assigned to any
host, there is not any restriction like IPv4.
Goals of IPv6
 Huge address space.
 Reduce the size of routing tables (possibly at the cost of wasting address
space).
 Simplify protocol to speed routers.
 Better security.
 Better type-of-service (to support real-time).
 Aid multicasting.
 Allow roaming hosts to maintain a constant address.
 Allow for future evolution.
 Be backwards compatible!

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Advantages of IPv6
Besides providing an almost limitless number of unique IP addresses for global end-to-end
reachability and scalability, IPv6 has the following additional advantages:
 Simplified header format for efficient packet handling.
 Larger payload for increased throughput and transport efficiency.
 Hierarchical network architecture for routing efficiency.
 Support for widely deployed routing protocols (OSPF, BGP, etc.)
 Autoconfiguration and plug-and-play support.
 Elimination of need for network address translation (NAT) and application layered
gateway (ALG).
 Increased number of multicast addresses.

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What is Ethernet?
Ethernet is a standard communication protocol embedded in software and hardware devices. It
is the traditional technology for connecting wired local area networks (LANs), enabling devices
to communicate with each other via a protocol. Ethernet provides services on the Physical
(Layers 1) and Data Link Layer (Layers 2) of OSI reference model.
Systems that use ethernet communication divide their data into packets, which are also known
as frames. These frames further contain source and destination address, a mechanism which
was used to detect errors in the data and retransmission requests.
As a data-link layer protocol in the TCP/IP stack, Ethernet describes how network devices can
format and transmit data packets so other devices on the same local or campus area network
segment can recognize, receive and process them. An Ethernet cable is the physical, encased
wiring over which the data travels.
 Example
Any device accessing a geographically localized network using a cable i.e., with a wired rather
than wireless connection likely uses Ethernet whether in a home, school or office setting. From
businesses to gamers, diverse end users depend on the benefits of Ethernet connectivity,
including reliability and security.
What if compared with wireless LAN?
Compared to wireless LAN technology, Ethernet is typically less vulnerable to disruptions
whether from radio wave interference, physical barriers or bandwidth hogs. It can also offer a
greater degree of network security and control than wireless technology, as devices must
connect using physical cabling making it difficult for outsiders to access network data or hijack
bandwidth for unsanctioned devices.
Ethernet Evolution through four Generations
Ethernet

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Ethernet Standards and Protocols
IEEE shorthand identifiers, such as 10Base5, 10Base2, 10BaseT, and 10BaseF include three
pieces of information:
 The number 10: At the front of each identifier, 10 denotes the standard data transfer
speed over these media - ten megabits per second (10Mbps).
 The word Base: Short for Baseband, this part of the identifier signifies a type of
network that uses only one carrier frequency for signaling and requires all network
stations to share its use.
 The segment type or segment length: This part of the identifier can be a digit or a
letter:
o Digit - shorthand for how long (in meters) a cable segment may be before
attenuation sets in. For example, a 10Base5 segment can be no more than 500
meters long.
o Letter - identifies a specific physical type of cable. For example, the
o T at the end of 10BaseT stands for twisted-pair.
Designation Supported Media Maximum
Segment
Length
Transfer
Speed
Topology
10Base-5 Coaxial 500m 10Mbps Bus
10Base-2 Thin Coaxial (RG-58
A/U)
185m 10Mbps Bus
10Base-T Category3 or above
unshielded twisted-
pair (UTP)
100m 10Mbps Star, using either
simple repeater hubs
or Ethernet switches
10Base-F Fiber Optic Cabling 2000m 10Mbps Star, using two fiber
optic cables to
connect to hub

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OSI Model
Description
The Open System Interconnection Reference Model (OSI Reference Model or OSI Model)
is an abstract description for layered communications and computer network protocol design.
It was developed as part of the Open Systems Interconnection (OSI) initiative.
Layers of OSI Model
In its most basic form, it divides network architecture into seven layers which, from top to
bottom, are the Application, Presentation, Session, Transport, Network, Data-Link, and
Physical Layers. It is therefore often referred to as the OSI Seven Layer Model.
Task Assignment
The OSI model divides the tasks involved with moving information between networked
computers into seven smaller, more manageable task groups. A task or group of tasks is then
assigned to each of the seven OSI layers.
Working
A layer is a collection of conceptually similar functions that provide services to the layer above
it and receives service from the layer below it. On each layer an instance provides services to
the instances at the layer above and requests service from the layer below. For example, a layer
that provides error-free communications across a network provides the path needed by
applications above it, while it calls the next lower layer to send and receive packets that make
up the contents of the path. Conceptually two instances at one layer are connected by a
horizontal protocol connection on that layer.
Layers of OSI Model

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1) Physical Layer
 The physical layer is responsible for movements of individual bits from one hop
(node) to the next.
◦ Physical characteristics of interface and medium: pin assignment,
connector, cables
◦ Representation of bits: encoding
◦ Data rate
◦ Synchronization of bits
◦ Line configuration: point-to-point, multipoint
◦ Physical topology
◦ Transmission mode: simplex, half-duplex, full-duplex
2) Data Link Layer (DLL)
 The data link layer is responsible for moving frames from one hop (node) to the next.
◦ Framing
◦ Physical addressing
◦ Flow control
◦ Error control
◦ Access control
From DLL To DLL
From NL To NL

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Hop to Hop Delivery
3) Network Layer (NL)
 The network layer is responsible for the delivery of individual packets from the
source host to the destination host.
o Logical addressing
o Routing
Source-to-Destination Delivery

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4) Transport Layer (TL)
 The transport layer is responsible for the delivery of a message from one process to
another.
o Service-point addressing
o Segmentation and reassembly
o Connection control
o Flow control
o Error control
Reliable Process-to-Process Delivery of a Message

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5) SessionLayer
 The session layer is responsible for dialog control and synchronization.
6) Presentation Layer
 The presentation layer is responsible for translation, compression, and encryption.
7) Application Layer
 The application layer is responsible for providing services to the user.

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Transmission Impairment
What is Transmission Impairment?
Signals travel through transmission media, which are not perfect. The imperfection causes
signal impairment. This means that the signal at the beginning of the medium is not the same
as the signal at the end of the medium. What is sent is not what is received.
What results out of Transmission Impairment?
1) Attenuation
a. Means loss of energy that results in weaker signals.
b. When a signal travels through a medium it loses energy overcoming the
resistance of the medium.
c. Amplifiers are used to compensate for this loss of energy by amplifying the
signal.
` Measurement of Attenuation:
To show the loss or gain of energy the unit “decibel” is used. It is denoted by “dB”. The
measurement formula for attenuation is:
dB = 10log10P2/P1
P1 is the input signal and P2 is the output signal.
Process:

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2) Distortion
a. Means that the signal changes its form or shape
b. Distortion occurs in composite signals
c. Each frequency component has its own propagation speed traveling through a
medium.
d. The different components therefore arrive with different delays at the receiver.
e. That means that the signals have different phases at the receiver than they did
at the source.
Process:
3) Noise
a. There are different types of noise
b. Thermal - random noise of electrons in the wire creates an extra signal
c. Induced - from motors and appliances, devices act as transmitter antenna and
medium as receiving antenna.
d. Crosstalk - same as above but between two wires.
e. Impulse - Spikes that result from power lines, lighting, etc.
Process: