IP address

Question

In the network 200.10.11.144/27, the fourth octet (in decimal) of the last IP address of the network, which can be assign to a host is__________

Comments

158?

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yes, it will be .158

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4th octet means?

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200.10.11.100|00000
.
.
.
.
200.10.11.100|11111
This will be the network. But Last address will be used as DBA
Hence usable last address for host will be 1 less

= 200.10.11.10011110 = 200.10.11.158
Last 8 bits = 158

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yes ,I got answer

but my question is

1)why it is called 4th octet (It should be 4th supernet) , isnot it?

2) We are not considered 1st and last bit in time of host calculation

U only not considered last bit(why also u not eliminate 1st bit ) ?

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For part A: each ip has 4 octate : A:B:C:D each having 8 bits.

FOr part B  We are not considered 1st and last bit in time of host calculation  8 because 1st ip is subnet id if few year back we cannot assign that ip , and if all host bits are 1 then it became DBA. hence we need to neglact these, now a days cisco router can use subnet id to assign a host.

see if question ask only ip then it will be 2ⁿ if ask for host to assign then 2ⁿ-2

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thanks:)