Subnetting

Logical Connection
• Protocols
• IP Address
• Network Model
– Peer to Peer (Workgroup)
– Client-Server based (Domain)
PROTOCOL
• A protocol is a set of defined rules for
communication:
Type of protocols:
• Connection less
• Connection oriented
Connection Less
• No acknowledgement require
• Use for voice/video traffic
• Example : UDP (User Data Program Protocol)
Connection Oriented
• Acknowledgement require
• Use for data traffic
• Example : TCP (Transmission Control Protocol)
Traffic Types
• Data
• Voice
• Video
• Reliability Should be High
• Speed Not matter
• Reliability Not matter
• Speed Should be High
Internet Protocol Addressing
• A unique IP address is required for each host and
network component that communicates using
TCP/IP.
• 32 Bit Address (4 bytes)
• Decimal
• Virtual (logical)
• Syntax
1B. 1B. 1B. 1B
Octet (8 bits)
Internet Protocol Addressing
IP Address Conversion from Binary to Decimal
Internet Protocol Addressing
Address Classes
Class Range
A 1—126
B 128—191
C 192—223
D 224—239
E 240—255
1st Octet Rule: 1st octet tells the class of IP
Internet Protocol Addressing
Parts of IP address
• Network
• Host
IP Addressing—Three Classes
• Class A: NET.HOST.HOST.HOST
• Class B: NET.NET.HOST.HOST
• Class C: NET.NET.NET.HOST
Types of IP classes
• Private
• Public
A : Expensive (N.H.H.H)
B : Moderate (N.N.H.H)
C : Expensive (N.N.N.H)
IP Network Address Classes
01111111 00000000
10111111
11011111 11111111
00000000 00000000
11111111
11111111 00000000 00000000
00000000
# Networks
126
16,384
2,097,152
# Hosts
254
65,534
16,777,214
Class
A
B
C
Class A 35.0.0.0
Class B 128.5.0.0
Class C 132.33.33.0 Network Address Space
Host Address Space
Example
IP Address Guidelines
• Check validity of IP
• Identify class on the basis of given ranges,
identify by left most octet
• calculate how much bits for network and for
host portion
Invalid IPs
• Every IP address whose host portion is
whole 0 or 1
• Host Portion whole 0 refer NID
• Host Portion whole 1 refer BID
192.168.1.0 NID
192.168.1.255 BID
1
254
Valid IPs
SUBNET MASK
• SUBNET MASK is the back bone of IP, SUBNET
MASK identifies network portion (NID) of the IP
• RULE
• All network bits “ 1 ”
• All Host bits “ 0 “
• Class A: NET.H.H.H
Subnet Mask 255.0.0.0
• Class B: NET.NET.H.H
Subnet Mask 255.255.0.0
• Class C: NET.NET.NET.H
Subnet Mask 255.255.255.0
Default IP Communication
• Rule
– NID of both ends should be same
– HID of both ends should be same
Network can be divided into
two broad categories:
PEER TO PEER
CLIENT/SERVER BASED
PEER TO PEER
CLIENT-SERVER
PEER TO PEER
NETWORKING
FACTORS
1. Size of organization
2. Level of security required
3. Types of business
4. Amount of network traffic
5. Needs of the network users
6. Network Budget
In peer-to-peer network, there are no
dedicated servers or hierarchy among
the computers. All of the computers
are equal and known as peers.
Normally, each computer functions as
both a client and a server, and there is
no one assigned to be an administrator
responsible for the entire network.


PEER TO PEER MODEL
This environment allows each client on a
network to communicate directly with all
other clients. Each computer performs as both
A server with software and devices to share
And
A client that requests network services.
Use Peer to Peer when
• Users are less than 10
• Security is not required
• Future growth is minimal
• Close locations
Don’t use Peer to Peer when
• Many no. of users
• Security is priority
• Network is expanding
• Remote locations
PEER TO PEER NETWORK
IMPLEMENTATION
1. Users manage their own computers
and resources.
2. Clients systems are usually located on
their desktops
3. Communication medias are very
simple and effective.
CLIENT/SERVER
BASED
NETWORKING
A server is a special computer that
does not function as a client or
workstation. Servers are dedicated
because they quickly serve request
from network clients and to ensure
the security of files and directories.


SERVER BASED MODEL
In this environment, all communications
pass through the server, which is very
powerful computer for sharing resources.
Server serves the client requests and
provide network security for directories
and files.
ADVANTAGES
• Data, users and shared resources are
centrally located, controlled and managed.
• A single USERNAME& PASSWORD is
used for network access.
• High level of security is available and
applied by Network Administrator.
• Thousands of users can be supported.
Network Classification
• Often classified according to geographical
size.
• Common Classification
– LAN (Local Area Network)
– WAN (Wide Area Network)
Network Classification
• LAN
(Local Area Network)
– Transfer data at high speed
– Exists in a limited geographical area
– Technology is generally less expensive
Network Classification
• WAN (Wide Area Network)
– Exists in an unlimited geographical area
– More error chances due to the distance data
travels
– Interconnect multiple LANs
– More complex and Sophisticated than LANs
– Technology is Expensive
Server based Networking
Resources are located on a central server
or group of servers, who is specifically
designed to provide services for the other
computer/clients on the network.
Advantages of Server based
Networks
• Share centralized resources
• Centralized Management of security
• Centralized backup of all network
• Support of virtually unlimited numbers of
users
NT Network Models
• Domain
Is the collection of the computer which uses
common account database. Account database is
called SAM ( Security Access Manager ) in NT
Environment.
• Workgroup
Is the Microsoft’s name of Peer to peer Networks