서브넷팅 예제

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LAB> 서브넷예제2 문제 풀이
192.168.100.0/27 로 서브네팅을 해야 A ~ C 기관의 30개의 호스트들에게
IP주소를 부여할 수 있다. 

Subnet Bitmap                       서브넷 마스크       Prefix 
110nnnnn.nnnnnnnn.nnnnnnnn.ssshhhhh 255.255.255.224     /27   
                           (128+64+32 = 224)

첫 번째 네트워크
Subnet ID : 192.168.100.0
Broacast addr : 192.168.100.31
가용 IP주소 : 192.168.100.1 - 192.168.100.30

두 번째 네트워크
Subnet ID : 192.168.100.32
Broacast addr : 192.168.100.63
가용 IP주소 : 192.168.100.33 - 192.168.100.62

세 번째 네트워크
Subnet ID : 192.168.100.64 
Broacast addr : 192.168.100.95
가용 IP주소 : 192.168.100.65 - 192.168.100.94

네 번째 네트워크
Subnet ID : 192.168.100.96
Broacast addr : 192.168.100.127
가용 IP주소 : 192.168.100.97 - 192.168.100.126

다섯 번째 네트워크
Subnet ID :  192.168.100.128
Broacast addr :  192.168.100.159
가용 IP주소 : 192.168.100.129 - 192.168.100.158


-- PC1 --
IP address : 192.168.100.1
Subnet Mask : 255.255.255.224
Default Gateway : 192.168.100.30
-- PC1 --
-- PC2 --
IP address : 192.168.100.33
Subnet Mask : 255.255.255.224
Default Gateway : 192.168.100.62
-- PC2 --
-- PC3 --
IP address : 192.168.100.65
Subnet Mask : 255.255.255.224
Default Gateway : 192.168.100.94
-- PC3 --

-- Router1 --
! fa0/0
enable
conf t
 hostname R1
 int fa0/0
 ip address 192.168.100.30 255.255.255.224
 no sh
!
 int fa0/1
 ip address 192.168.100.97 255.255.255.224
 no sh
!
 ip route 192.168.100.32 255.255.255.224  192.168.100.98
 ip route 192.168.100.64 255.255.255.224  192.168.100.98
 ip route 192.168.100.128 255.255.255.224 192.168.100.98
!
-- Router1 --

-- Router2 --
! fa0/0
enable
conf t
 hostname R2
 int fa0/0
 ip address 192.168.100.62 255.255.255.224
 no sh
!
 int fa0/1
 ip address 192.168.100.98 255.255.255.224
 no sh
!
!
 int fa1/0
 ip address 192.168.100.129 255.255.255.224
 no sh
!
 ip route 192.168.100.0 255.255.255.224  192.168.100.97
 ip route 192.168.100.32 255.255.255.224  192.168.100.130
 ip route 192.168.100.64 255.255.255.224  192.168.100.130
!
-- Router2 --
-- Router3 --
! fa0/0
enable
conf t
 hostname R3
 int fa0/1
 ip address 192.168.100.94 255.255.255.224
 no sh
!
!
 int fa0/0
 ip address 192.168.100.130 255.255.255.224
 no sh
!
 ip route 192.168.100.0 255.255.255.224  192.168.100.129
 ip route 192.168.100.32 255.255.255.224  192.168.100.129
 ip route 192.168.100.96 255.255.255.224  192.168.100.129
!
-- Router3 --
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