The document provides an introduction to networking concepts and Cisco technologies. It defines networking and network topology, discusses the OSI model and TCP/IP, and describes common network devices like switches, routers, and firewalls. It also covers IP addressing, routing protocols, and basic router and switch configuration.
9. What is Network ?
A Network is a collection of devices and end
systems connected to each other via a
medium for the purpose of sharing
resources.
10. What is Networking ?
Networking is the practice of communicating
group of computing devices with each other.
11. Types Of Computer Networks
Configurational
Network
Peer to Peer
Network
Server to Client
Geographical
Network
LAN
(Local Area
Network)
PAN(Personal
Area Network)
CAN (Campus
Area Network)
MAN
(Metropolitan
Area Network)
WAN
(Wide Area
Network)
12. What is Network Topology ?
Network Topology is the Architecture which
defines the arrangement of devices in a
Network.
15. What is OSI Model?
Open Systems Interconnection Basic Reference
Model (OSI Reference Model or OSI Model) is an
abstract description for layered communications
and computer network protocol design.
It was developed by ISO(International
Organization for Standardization).
It divides network architecture into seven layers
which, from top to bottom, are the Application,
Presentation, Session, Transport, Network, Data-
Link, and Physical Layers.
16. What is TCP/IP ?
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:
the Transmission Control Protocol (TCP) and
the Internet Protocol (IP), which were the first two
networking protocols defined in this standard
17. Application Layer
Application Layer, 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, defines network application services like
file transfer, network management.
Identification of services is done using port numbers.
Application layer, Presentation layer, Session layer of OSI
model.
Responsible for converting data into standard format.
Encoding-decoding, encryption-decryption and
compression.
18. Transport Layer
Transport layer, deals with actual manipulation of data and
prepares it for delivery through network.
Two important protocols are used in Transport layer are
TCP and UDP.
If data is too large for the single frame, then it 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.
It is responsible for ensuring data is sent and received
successfully and verifying delivery of packets.
Identification services, sequencing, flow control, error
correction, segmentation, reassembling is done here
19. Internet Layer
Internet layer deals with, finding the way to the
destination.
Internet layer 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.
20. 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).
“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.
Wan protocols like PPP, HDLC, and frame relay are used.
Responsible for error detection.
22. NIC
Network Interface Card connects computer to
network.
It works on Physical Layer of OSI Model
23. HUB
It is a central memory-
less networking device
with multiple ports used
for connecting
Segments of LAN.
It works on Physical
Layer of OSI Model.
Type of Hub-
Passive Hub
Active Hub
Intelligent Hub
24. SWITCH
It is a central networking
device that connects
devices together in a
network by using packet
switching techniques.
It has memory and it
works on Data Link Layer
of OSI Model.
25. ROUTER
It is a networking device
that connects two or
more networks together.
It works on Network
Layer of OSI Model
Types of Router
Wired
Wireless
27. What is Ethernet?
Ethernet is a family of computer networking
technologies and architectures for local area
networks (LANs) and metropolitan area
networks (MANs).
It was standardized as IEEE 802.
32. IP Addresses
An IP address is an address used to uniquely identify a
device on an IP network.
The IPV4 address is made up of 32 binary.
32 binary bits are broken into four octets (1 octet = 8 bits)
Dotted decimal format (for example, 172.16.81.100)
The IPV6 address is made up of 128 binary bits which can
be divisible into a network portion and host portion with
the help of a subnet mask.
128 binary bits are broken into six octets (1 octet = 8 bits)
Colon Hexadecimal format (for example,
1A2:16:2C:B1:00:2A)
34. IP Address Classes
Class A: The first octet is the network
portion. Octets 2, 3, and 4 are for
subnets/hosts
Class B: The first two octets are the network
portion. Octets 3 and 4 are for subnets/hosts
Class C: The first three octets are the network
portion. Octet 4 is for subnets/hosts
35. Types Of Special IP Address
Loop Back IP: This IP range is used to check
the NIC card. 127.0.0.1 - 127.255.255.255
Link Local IP: This IP range is provided when
Services are not provided by Router.
169.254.0.1 - 169.254.255.255
Private IP: This IP range are used in private
network.
Address Class Reserved Address Space
Class A 10.0.0.0 - 10.255.255.255
Class B 172.16.0.0 - 172.31.255.255
Class C 192.168.0.0 - 192.168.255.255
36. Network Subnet Masks
Distinguishes which portion of the
address identifies the network and which
portion of the address identifies the
node.
Default masks:
Class A: 255.0.0.0
Class B: 255.255.0.0
Class C: 255.255.255.0
37. Subnetting
Creates multiple logical networks that exist
within a single Class A, B, or C network.
Reduced network traffic
Optimized network performance
Simplified management
Facilitated spanning of large geographical
distances
38. VLSM
Variable Length Subnet Mask is a better way
of subnetting a network with lesser wastage
of IP Address.
40. 3 Level Hierarchy Cisco Router
1. Core Layer
Routers that are used by the Global ISPs and are also known as
backbone routers.
Core layer routers are best routers than all and are costly
routers
2. Distribution Layer
Routers which are used by ISP’s and are also known as ISP layer
routers.
Distribution layer routers are batter in speed, processing and
RAM than access layer routers.
These routers are costly than access layer routers.
3. Access Layer
Routers which are used by the small organizations and are also
known as Desktop routers or company layer routers.
Access layer routers are of low speed, low processing power,
low RAM and lower no of ports and are also low price
41. Cisco Router
Router is a device which makes connection
possible between two or more different
networks present at same or different
geographical locations.
It works on 3rd layer of OSI Model (i.e. on
network layer)
It does two basic things:
Select the best path from the routing table.
Forward the packet on that path.
Routers are classified in two classes:
Manageable
Unmanageable
44. NETWORK SWITCH
A network switch is a device used to connect
network segments or network devices.
Network switch receive messages and send
them to the targeted audience.
It is a telecommunication device that uses
the packet switching to receive, process and
forward data to the destination address.
45. Contd..
Network switch forwards data to one or
multiple devices that need to receive it.
Switches are the multiport network bridges
that process and forward data at the data link
layer(layer 2 of OSI model).
The switches that process data at the
network layer or above it, known as layer 3
switches or multi-layer switches.
46. 1. Setup Mode
– Continue with configuration dialog?[Yes/No]
2. User Mode
– No
– Router>
3. Privileged Mode
– Router>enable
– Router#
4. Global Configuration Mode
– Router#configure terminal
– Enter configuration commands, one per line. End with CNTL/Z.
– Router(config)#
5. Interface Mode
– Router(config)#interface [port name] [port number]
– Router(config-if)#
Eg.Router(config)# interface FastEthernet0/0
Modes Of The Router and Switches
47. Basic Configuration of Router and
Switch
Changing Hostname:
Syntax: Router(config)#hostname xyz
Status:
Syntax: Router #show running-config
Saving Data To NVRAM:
Syntax: Router #copy running-config startup-config
49. 1. User Mode Password
(Used in both Router and Switch)
Syntax:
Router(config)#line console 0
Router(config-line)#password 1234
Router(config-line)#login
Router(config-line)#exit
50. 2. Privilege Mode Password
(Used in both Router and Switch)
Syntax:
Router(config)#enable password 123
Router(config)#exit
51. 3. Secret Password
(Used in both Router and Switch)
Syntax:
Router(config)#enable secret 123456
Router(config)#exit
52. 4. Telnet Password
(Used in both Router and Switch)
Syntax:
Router(config)#line vty 0
Router(config-line)#password 0000
Router(config-line)#login
Router(config-line)#exit
53. 5. Auxiliary Password
(Used in Router)
Syntax:
Router(config)#line aux 0
Router(config-line)#password 8520
Router(config-line)#login
Router(config-line)#exit
59. STP(Spanning Tree Protocol)
To avoid the loop back this by-default
protocol is used by switches.
A root bridge is selected which controls the
whole circuit.
Process:
Selecting root-bridge(on the basis of MAC
address)
Selecting root port
Select designated port and non-designated ports
60. PVRST(Per VLAN Rapid Spanning Tree
Protocol)
It a upgraded version of STP
It has faster port status
When any port stops working it changes the
Blocked Port to a Forwarding Port
62. is the process that a
router uses to forward packets
toward the destination network.
Routing
Types Of Routing
1. Static routing
2. Default routing
3. Dynamic routing
63. Static Routing
In static routing,
The Administrator must configure all possible
routes to each and every router to ensure full
connectivity.
64. Default Routing
In default routing,
It is used when No specific rote can be
determined for a given IP destination address.
65. Dynamic Routing
It allows routing tables to automatically
propagate routing information using different
protocols.
3. Dynamic Routing
Distance Vector
Routing Protocol
RIP, RIP 2, IGRP
Link State
Routing Protocol
OSPF, IS-IS
Hybrid or
Advanced
Routing Protocol
EIGRP
66. Distance Vector Protocol
It works with Bellman Ford Algorithm.
Performs periodic updates
Uses class-full routing protocol
Full routing tables are exchanged
Updates are through Broadcast.
Also known as “ Routing by Rumor”
Example: RIP, RIP2, IGRP
69. Link State Protocol
It works with Dijkstra Algorithm
Performs link state updates
Uses classless routing protocol
Missing routes are exchanged
Updates are through multicast
Also known as “Routing by Intelligence”
Example: OSPF, IS-IS
70. OSPF
It broadcasts out its entire routing table every
30 sec regardless of whether outer wants to
heart it or not.
Hello Packet Timer: 10 sec
Multicast IP: 224.0.0.5
71. Hybrid Protocol or Advanced
Distance Vector
It uses Dual Algorithm
Performs classless routing protocol
Missing routes are exchanged
Updates are through multicast
Also known as “Routing by Intelligence”
Example: EIGRP
73. SSH and Telnet
This Protocols provides a direct control to
Router from a connected PC.
Secure Shell is more secured then Telnet.
74. Frame Relay
Frame Relay is a packet-switching high
performance protocol telecommunication
service designed for cost-efficient
transmission for traffic between LAN and
between end points in WAN
76. IP Services provides client support
services in the areas of Anti-Piracy, Fraud
Prevention, Legal Compliance and
Program Management.
Important Feature Sets are:
NAT(Network Address Translation)
PAT(Port Address Translation)
DHCP(Dynamic Host Configuration
Protocol)
HSRP(Hot Standby Router Protocol)
77. Access Control List(ACL)
It is collection of permit and deny conditions.
It provide security by blocking unauthorized
users and allowing authorized users.
It filters unknown packets
Types of ACLs:
Standard ACL
Extended ACL
Named ACL
78. ACL Standard
Filter based on source
Permits or denies the entire TCP/IP protocol
suite
The Normal Range: 1 to 99
The Expanded Range: 1300 to 1999
79. ACL Extended
Filter based on source and destination
Permits or denies the specific IP protocol and
port number
The Normal Range: 100 to 199
The Expanded Range: 2000 to 2699
80. Network Address Translation(NAT) is
used to translate a private IP address
to a Public IP address.
Whenever private IP users need
internet access, NAT is used to map it
to a corresponding Public IP
83. PAT(Port Address Translation)
It is an extension to NAT that permits
multiple devices on a LAN to be mapped to a
single public IP address.
84. DHCP
Dynamic Host Configuration Protocol is a
standardized network protocol used by IP
networks.
It is controlled by a DHCP Server that
dynamically distributes IP address to the
computer connected in range.
85. HDLC
High-Level Data Link Control is a group of
protocols or rules for transmitting data
between network points
86. PPP
The Point-To-Point Protocol provides a
standard method for transporting multi-
protocol datagrams over point-to-point links.