Subnetting of IP Address

Network Number for Each Network netA netB netCnetD A B Unique Network Number for each Network Different host addresses in same Network 4 Network Numbers for 8 systems s0 e0e1

Routing Table of Router B IP Routing Table Destination Network NumberInterface e s s e1

Sub-Network N umber for E ach N etwork Only 1 Class B Network Number for 4 networks –more effective We should apply subnetmask in these cases netA netB netCnetD A B

Routing Table of Router B IP Routing Table Destination Network NumberInterface s s e e1

Benefit of Subnetting Address utilization if more Efficient Minimized the side effect of Broadcast message –broadcating storm exhausts the bandwithd of network –minimize broadcasting storm....

Subnet Mask IP Network Address Default Subnet Mask 8-bit Subnet Mask Use host bits, starting at the high order bit position 1bit for network number, 0 bit for host address

Subnet Mask Bits = = = = = = = =

Subnet Mask without Subnets The router performs a logical AND operation to obtain the destination network number Subnets not in use -- the default NetworkHostsubnet

Subnet Mask with Subnets Network Number extended by 8 bits NetworkHost

Class B Subnetting no. bitssubnet maskno. subnetsno. hosts (0) (2) (6) (14) (30) (62) (126) (254) (510) (1022) (2046) (4094) (8190) (16382) 2

Class C Subnetting no. bitssubnet maskno. subnetsno. hosts (0) (2) (6) (14) (30) (62) 2

Subnet & Host range / (0) (32) (64) (96) (128) (160) (192) (224)

Subnet & Host range (cont.) / (32) (33) (34) (35) (36) (37) (60) (61) (62) (63)

Subnetting Tip Bit : 2 subnets range1: 0~127 range2: 128 ~ Bits: 4 subnets 3 Bits: 8 subnets 4 Bits: 16 subnets

Exercise addresssubnet mask class subnet broadcast

Subnet Case 1 20 subnets 5 hosts per subnet class C address :

Subnet Case 1 (cont.) IP Host Address: Subnet Mask: subnet addres: host address: ~ broadcast address: Networksubnethost