This tutorial gives very good understanding on Computer Networks After completing this tutorial,You will find yourself at a moderate level of expertise in knowing Advance Networking(CCNA), from where you can take yourself to next levels.

1. BASICTOADVANCED
NETWORKINGTUTORIALS
PRESENTED BY-:
VARINDER SINGH WALIA

2. SOME BASICS
OF
NETWORKING

3. TOPOLOGY
Topology is the structural design of communication model depicted physically or logically.
PHYSICAL TOPOLOGY
 Physical topology is the placement of the various components of a network, including
device location and cable installation
 Example: LAN has one or more physical links to other devices in the network;
graphically mapping these links results in a geometric shape that can be used to
describe the physical topology of the network.

4. LOGICAL TOPOLOGY
ICMP – INTERNET CONTROL MESSAGE PROTOCOL
Used to communicate between two devices . Ping command help in implementation of
ICMP
IPx/SPx - INTERNET PACKET EXCHANGE / SEQUENCE PACKET EXCHANGE
Developed by Novell company for LAN and MAN
NET- Bios - Network Basic Input / Output System
It is a program that allows applications on different computers to communicate within a
local area network (LAN).
It was created by IBM for its early PC Network, was adopted by Microsoft, and has
since become a de facto industry standard.
Nwlink IPx/ SPx
NWLink packages data to be compatible with client/server services on NetWare
Networks.
SMTP – SIMPLE MAIL TRANSFER PROTOCOLS
It is used for electronic mailing

5.  POP3 - POST OFFICE PROTOCOL 3
 It is the most recent version of a standard protocol for receiving e-mail.
 POP3 is a client/server protocol in which e-mail is received and held for you by your Internet
server.
 FTP - FILE TRANSFER PROTOCOL
 It is a standard network protocol used to transfer computer files between a client and server on a
computer network.
 TFTP – TRIVIAL FILE TRANSFER PROTOCOL
 It is an Internet software utility for transferring files that is simpler to use than the File Transfer
Protocol but less capable.
 It is used where user authentication and directory visibility are not required.
 It is used as backup to recovery files
 HTTP – HYPER TEXT TRANSFER PROTOCOL
 It is an application protocol for distributed, collaborative, hypermedia information systems.
 It is the foundation of data communication for the World Wide Web.
 Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text
 HTTP functions as a request–response protocol in the client–server computing model.

6.  HTTPS – HYPER TEXT TRANSFER PROTOCOL SECURE
 It is advanced version of http
 DHCP – DYNAMIC HOST CONFIGURATION PROTOCOL
 It is a client/server protocol that automatically provides an Internet Protocol host with its IP
address and other related configuration information such as the Subnet Mask and Default
Gateway.
 TELNET-
 It is an application layer protocol used on the Internet or local area networks to provide a
bidirectional interactive text-oriented communication facility using a virtual terminal
connection
 SSH – SECURE SHELL PROTOCOL
 It is used for security purpose like authentication for username , password etc.
 ARP – ADDRESS RESOLUTION PROTOCOL
 It is a protocol used by the Internet Protocol to map IP network addresses to the hardware
addresses used by a data link protocol
 RARP – REVERSE ADDRESS RESOLUTION PROTOCOL
 It is used to convert MAC address to IP address

7. ADVANCED
NETWORKING

8. ROUTER
 It is a route device which defines router of data
 It reads the packet and filter them
 It works on IP address network
 It manages all traffic inside the routing
 Here we are dealing with ROUTER 2811

9. SWITCH
 Switch is a computer networking device that connects devices together on a computer
network, by using packet switching to receive, process and forward data to the
destination device.
 Here we are going to deal with SWITCH 2960-24T

10. IPADDRESSING and SUBNETTING
IPADDRESSING
 Internet Protocol address (IP address) is a numerical label assigned to each device
(e.g., computer, printer) participating in a computer network that uses the Internet
Protocol for communication.
 Types of IP address
 IPv4 – Internet Protocol version 4
 IPv6 – Internet Protocol version 6

11. SUBNETTING
 It is process of dividation of IPs into subparts.
 We require subnetting in order to reduce the cost
 Example: Suppose we want to buy 100 IPs and each having cost of 260
 => Total Cost = 260 *100=> 26000
 But through subnetting we need only single IP which is divided through subnetting into
different IPs as below:
 Example: 192.168.1.0 Main IP
192.168.1.1
192.168.1.2
192.168.1.3 and so on……………

12. CONCEPT OF CLASSES
 There are five types of classes namely A,B,C,D,E described below.
 But in Practical Networking we prefer CLASS C only.
S.N
O
CLASS NETWORK
BIT
HOST
BIT
RANGE SUBNET WILDMASK
1 A 8 24 1-126 255.0.0.0 0.255.2555.255
2 B 16 16 128-191 255.255.0.0 0.0.255.255
3 C 24 8 192-223 255.255.255.
0
0.0.0.255
4 D BROADCAST 224-239
5 E RESEARCH 240-255

13. CORPS INFORMATION SYSTEM CONTROL OFFICER
(CISCO)
 Cisco Systems is an American multinational technology company headquartered in San
Jose, California, that designs, manufactures and sells networking equipment.
 It is considered to be the biggest networking company in the world.
 It is a MNC which deals in Networking Hardware Devices.
 It provides three certifications
 CCNA – CISCO CERTIFIED NETWORK ASSOCIATE/ADMINISTRATOR
 CCNP – CISCO CERTIFIED NETWORK PROFESSIONAL
 CCIE – CISCO CERTIFIED INTERNETWORK EXPERT
NOTE: Here we are going to deal with CCNA

14. CISCO CERTIFIED
NETWORK
ADMINISTRATOR/
ASSOCIATE
(CCNA)

16. ROUTING

17. ROUTING
 It means allocating the suitable and appropriate path by the router to the message/packets
from source to destination i.e Tx to Rx and vice versa.
 The device used for this mechanism used is called ROUTING and the device used is called
ROUTER
 Here we are going to deal with ROUTER 2811
 CISCO Routers have four ports for inserting WIC-2T card generating two serial ports from
each card.
 It has two Fast Ethernet ports namely fa 0/0 and fa 0/1 used for connecting devices through
copper straight wire
 It also have 8 serial ports generated two by each WIC-2T card. These ports are used for
only serial connections through Serial DATA TRANSFER EQUIPMENT (DTE) wire

18. BASIC CONFIGURATION
 It is done on Router
 Router with Switch and PC
 Select Router 2811
 Double click on it and a box will appear.
 Switch Off the Power
 Insert WIC-2T Cards as per requirement .
 Each card will give rise to Two different Serial Ports like 0/0/0 ,0/1/0 etc.
 Then take Switch-2960 and connect both with Copper Straight Wire.
 At last attach PC with Switch using same wire.
 Then click on Router And Then CLI Mode.
 Then write the following configuration code on Router:

19. CONFIGURATION ON ROUTER
Press : no
 Router>enable
 Router # config terminal
 Router( config) #interface fastEthernet 0/0
 Router( config-if) # ip address 10.0.0.1 255.0.0.0
 Router( config-if)#no shut
 This will turn the light Green between Router And Switch
 Then click PC and provide suitable IP and then press tab which will automatically
assign a suitable subnet mask. And then close this window
 Now click command prompt and write the below command:
 Pc> ping_assigned ip of pc…..
 Then press enter

20. SERIAL PORT CONFIGURATION
 It is used for communication between two or more routers
 Two or more routers are attached with each other through Serial DTE wire at suitable
serial ports.
 CONFIGURATION ON BOTH ROUTERS
 Router > en
 Router # config terminal
 Router (config )# interface serial 0/0/0
 Router (config-if)# ip address 10.0.0.1 255.0.0.0
 Router (config –if)# no shut

21. STATIC ROUTING
 It is used where router uses manual IP configuration .
 It is used in small scale networks.
 In it we left all the directly attached network .
 Commands Used
 Router (config )# iproute_neighbor ip_subnet_via
 ADVANTAGES OF STATIC ROUTING
 Fast and Effective
 Moreover control selective path
 Less overload for router
 DISADVANTAGES OF STATIC ROUTING
 More overhead on administrator
 Load balancing is not easily possible

22. DEFAULT ROUTING
 It means a route for any network
 This route is specified with following syntax:
 Router (config)# ip route 0.0.0.0_0.0.0.0_via

23. DYNAMIC ROUTING
 It is simple and fast to implement
 In it we have to write only directly attached entire network
 Various DYNAMIC ROUTING techniques includes :
 ROUTER INFORMATION PROTOCOL(RIP)
 INTERIOR GATEWAY ROUTING PROTOCOL(IGRP)
 ENHANCED INTERIOR GATEWAY ROUTING PROTOCOL(EIGRP)
 OPEN SHORTEST PATH FIRST(OSPF)
 BORDER GATEWAY PROTOCOL(BGP)

24. ROUTER INFORMATION PROTOCOL (RIP)
 It is one of the oldest distance-vector routing protocols which employ the hop count as a
routing metric.
 RIP prevents routing loops by implementing a limit on the number of hops allowed in a
path from source to destination.
 The maximum number of hops allowed for RIP is 15, which limits the size of networks
that RIP can support.
 A hop count of 16 is considered an infinite distance and the route is considered
unreachable.
 In it we have to write only directly attached networks.
 Command used :
 Router (config)# router rip
 Router (config-router)# network_required network IP

25. ENHANCED INTERIOR GATEWAY ROUTING PROTOCOL
(EIGRP)
 EIGRP (Enhanced Interior Gateway Routing Protocol) is a network protocol that lets
routers exchange information more efficiently than with earlier network protocols
 It has characteristics of both distance vector and link state protocols
 EIGRP will route the same protocols that IGRP route .
 SYNTAX :
 Router (config)# router eigrp_PROCESS ID ( )
 Router (config-router)# network _ required network IP
NOTE: All Routers has same Process ID

26. OPEN SHORTEST PATH FIRST (OSPF)
 Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks.
 It uses a link state routing algorithm and falls into the group of interior routing protocols,
operating within a single autonomous system (AS).
 It uses the concept of WILD CARD MASK , which is complement of subnet
 It also uses the Process ID and Area
 NOTE: All routers have same Area but different Process ID
 SYNTAX:
 Router (config )# router ospf_ PID(range 1-65535)
 Router (config –router)# network_requires network IP_ wildcard mask_area_any value(range
0-4294967295)

27. BRODER GATEWAY PROTOCOL (BGP)
 Border Gateway Protocol (BGP) is a standardized exterior gateway protocol designed
to exchange routing and reachability information among autonomous systems (AS) on
the Internet.
 The protocol is often classified as a path vector protocol but is sometimes also classed
as a distance-vector routing protocol.
 This protocol use the ip of neighbor point for communication
 SYNTAX:
 Router (config)#router bgp_PID1
 Router (config –router)# neighbor_ip of end point_remote-as_PID2
 NOTE 1: Before applying this command apply Dynamic routing on each router
 NOTE 2: Each router has different Process ID
 NOTE 3:Do not write directly attached IP of network. All except directly attached IP
will be treated as neighbor
 NOTE 4: PID will be of current router only.

28. REDISTRIBUTION B/W RIP,STATIC,EIGRP AND OSPF
ROUTING
 Commands Used:
Router (config)#router rip
Router(config-router)#redistribute ospf 10 metric 10
Router(config-router)#redistribute eigrp 10 metric 10
Router(config-router)#redistribute static metric 10
Router (config-router)# router ospf 10
Router(config-router)#redistribute rip metric 10 subnets
Router(config-router)#redistribute eigrp 10 metric 10 subnets
Router(config-router)#redistribute static metric 10 subnets
Router(config-router)#router eigrp 10
Router(config-router)#redistribute rip metric 100 100 100 100 100
Router(config-router)#redistribute static metric 100 100 100 100 100
Router(config-router)#redistribute ospf 10 metric 100 100 100 100 100
Router(config-router)#do wr
Router(config-router)#exit

29. TELECOMMUNICATION
(VOIP)

30. INTODUCTION TO VOIP
 VOIP is an acronym for Voice Over Internet Protocol, or in more common terms phone
service over the Internet.
 If you have a reasonable quality Internet connection you can get phone service
delivered through your Internet connection instead of from your local phone company.
BASIC IDEA OF VOIP
 Continuously sample audio.
 Convert each sample to digital form.
 Send the resulting digitized stream accross an IP network in packets.
 Convert the stream back to analog for playback.
 Before the procedure above, the system must handle call setup.
 Phone number to IP.

31. ADVANTAGES OF VOIP
 Low call costs. ...
 Low cost of performing moves, ads and changes on a business VOIP phone system.
 Increased functionality and integration with other IT business systems.
 Ability to have your land-line phone number follow you anywhere.
 Low infrastructure costs. ...
 Future proof.
DISADVANTAGES OF VOIP
 Loss of service during outages.
 Without power VOIP phones are useless, so in case of emergencies during power
cuts it can be a major disadvantage.
 With VOIP emergency calls, it is hard to locate you and send help in time.
 Some times during calls, there may be periods of silence when data is lost while it
is being unscrambled.
 Latency and traffic.
 No standard protocol is applicable

32. VOICE OVER INTERNET PROTOCOL
(VOIP)
(VOIP)

33. SWITCHING

34. SWITCHING
VIRTUAL LOCALAREA NETWORK (VLAN)
 It is a smart device
 It divides switch into multiple parts in order to maintain security.
 Basic Configuration:
 Switch(config)#vlan ID(1-1005)
#vlan 10
#name ABC
#vlan 20
#name XYZ
#do show vlan
#do wr
#exit

35.  SWITCH TO SWITCH PROGRAMMIG
Switch#interface fa 0/0
#switchport access vlan 10
interface fa 0/3
# switchport access vlan 10
# interface fa 0/2
#switchport access vlan 20
# interface fa 0/4
#switchport access vlan 20
#do wr
#exit
:-> NOW apply the following commands:
Switch(config)# interface fa 0/24
#switchport mode trunk
#do wr
#exit

36. PER- VLAN SPANNING TREE
 Per-VLAN Spanning Tree (PVST) maintains a spanning tree instance for each VLAN
configured in the network.
 It uses ISL Trunking and allows a VLAN trunk to be forwarding for some VLANs while
blocking for other VLANs.
 Since PVST treats each VLAN as a separate network, it has the ability to load balance
traffic (at layer-2) by forwarding some VLANs on one trunk and other Vlans on another
trunk without causing a Spanning Tree loop.
 Commands for PVST on router:
Router(config)#interface fa 0/0
#no shut
Router(config)#int fa 0/0.10(10 is Ip of given PC’s)
#encapsulation_dot1Q_10
#ip_add_pc virtual IP_subnet
NOTE: Add similar above commands of number of even PC’s attached.

37. SECURITY

38. SECURITY
It is the network device protection in order to secure our network with help of
CCNA technology
 TYPES OF SECURITY :
 ACCESS CONTROL LIST : It is type of security in which we filter inbound
and outbound traffic
 Types of ACL:
1. STANDARD ACL : It is a type of ACL in which we block all the protocols
in our network.
 Commands for STANDARD ACL
Router(config)# ip_access-list standard_abc_deny_IP of n/w to be blocked_wildcard mask
#permit_any
#do wr
#exit
Router(config)# interface fa 0/0
#ip_access-group_abc

39. 2. EXTENDED ACL : It is a type of ACL in which we block a particular protocol as
well as particular IP
 Commmands for Extended ACL:
 Router(config) # ip_access-list_extended_abc
#deny_icmp_destination IP_wildcard mask_source IP_wildcard
mask
#permit_ip_any_any
#do wr
#exit
 Router(config)# interface fa 0/0
#ip_access-group_abc
#do wr
#exit

40. VIRTUAL TERMINAL TYPE (VTY)
 It is protocol used for remotely connection with other connection.
 REQUIREMENT
1. Client Side: There are two password used that are ON ENABLE and ON LINE
CONSOLE
• Commands on CLIENT SIDE:
Router>en
Router#telnet_10.0.0.1
#do show ip interface brief
2. MASTER SIDE:
• Commands on MASTER SIDE:
Router(config)# enable_password_123
#line_vty_0 15
#password 1234
# do wr
# exit

41. VIRTUAL PRIVATE NETWORK (VPN)
 VPN is a technology that creates an encrypted connection over a less secure network
 In this basically TUNNEL is made to keep data secure , through which only source and
destination clients can get the data.
 Commands for VPN:
Router(config)# interface_tunnel_number
# ip_address_virtual IP_subnet
# tunnel_source_serial_of router itself
#tunnel_destination_IP of end router
# do wr
# exit
NOTE: Also share the virtual ip on both end router with rip command.

42. NETWORK ADDRESS TRANSLATOR
 It is type of security in which we convert our private address into public address
 It is a part of ethical hacking in which there is use of fake IP
 TYPES Of NAT:
1. STATIC NAT: It is a type of NAT in which the client will fetch only single
fake IP everytime.
Commands for STATIC NAT:
Router(config)# ip_nat_inside_source_static_IP of pc of router
# interface fa 0/0
#ip_nat_inside
#interface serial 0/0/0
#ip_nat_outside
#do wr
#exit

43. 2.DYNAMIC NAT : It is a type of security in which we create a pool of fake IP’s
,because of which the user will receive a different fake IP
everytime within the range of given IP pool.
 Commands for DYANMIC NAT:
Router(config)# access-list_10_permit_actual router IP_wildcard mask
# ip_nat_pool_abc_50.0.0.3_50.0.0.10_netmask_subnet
# ip_nat_inside_source_list_10_pool_abc
#interface_fa_0/0
#ip_nat_inside
#interface_serial_port of router
#ip_nat-outside
#do_wr
#exit
3. Overload / NATPAD : It means that the single public IP assigned to your router can be used
by multiple internal hosts concurrently. This is done by translating source UDP/TCP ports in the
packets and keeping track of them within the translation table kept in the router .