compter networking

1. PRESENTATION
CN
GROUP 11
M.AZHAR(ROLL NO 23)
IHSAN AHMAD SABIR(ROLL NO 13)
FAKHAR FAREED(ROLL NO 38)
ASAD IQBAL(ROLL NO 45)

2. Classless Adressing
Defination:
Classless addressing is an IPV4
addressing architecture that Uses
variable-length subnet masking.

3. Clasasless Adressing:
In classful addressing the size of network is fixed
Each address range has a default subnet mask.
Classless Adressing however,decouples IP address
ranges from a default subnet mask ,allowing for
Variable- length subnet masking(VLSM)

4. How does classless addressing work:
At high level,classless addressing work by allowing IP addresses to be
assigned arbitrary network masks without respect to “Class”.
That means /8(255.0.0.0),/16(255.255.0.0),and /24(255.255.255.0)
Network masks can be assigned to any address that would have tra-
ditionally been in the class A,B or C range.

5. Notation:
Notation of classless addressing system .
p.q.r.s/n
Where p.q.r.s represent the IP address,and
n represent the mask bits .

6. Rules for classless Addressing system block:
A classles addressing system is created using a set of three rules
that are as follows:
Rule 1:Every classless addressing system will have contiguous
IPaddress.All the IP address in one classless addressing system
block Will be represented using CIDR block notation.

7. Rule 2:
The size of block must always be representable in the power
of 2 .The size of block is the total number of Ipaddress in the
Block .Any classless addressing system or classless interdomain
Routing (CIDR) block size will always be in form of 21,22,23,24,
25,etc.

8. Rule 3:
The block’s first IP address must always be divisible
by the size of the block.

9. Advantages of the classless addressing:
Classless addressing helped solve three major problems and delivers
These advantages.
• More IP address allocations. Today, we know IPv6 is our long-term IP
address solution to theIP address exhaustion problem. However, IPv6 is not
yet widely used. In the early 1990s, it was clear we would rapidly exhaust the
IPv4 address space if nothing changed. As a result, classless addressing was
used as a medium-term solution to help us stretch the life of IPv4.

10. • More balanced use of IP address ranges.
Classless addressing decoupled the relationship between
network size and IP address and allowed for balanced use
across what used to be the Class A, B, and C ranges. Far
less wasted addresses.

11. • More efficient routing. VLSM and subnetting make route
aggregation and classless routing protocols possible.
With route aggregation (sometimes called route summarization
or supernetting), routing tables can be smaller, reducing resource
consumption on routers, and saving bandwidth