I want to make sure I have this class B subnet right, plz

Here's my first go at a class B problem. Could someone check to make sure it's right? Thanks.

Given:
Network address/128.77.0.0
# of needed usable subnets/60
# of needed usable hosts/1000

My answers:
custom subnet mask: ?
Total # of subnets: 64
Number of usable subnets: 62
Total # of host addresses: 1024
Number of usable addresses: 1022
# of bits borrowed: 6

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Comments

Pash

you forgot to fill in your subnet mask, but the rest is good.

Tricon7

Pash wrote:

you forgot to fill in your subnet mask, but the rest is good.

That's the problem; I'm not sure of the subnet mask.

theseman

Well you know that you are subnetting a class B. (Default mask is 255.255.0.0 /

11111111.11111111.00000000.00000000)

And you know you borrowed 6 bits (I think thats what you wrote anyhow).

So.. just make the next 6 zeroes... ones

11111111.11111111.11111100.00000000

aka

255.255.252.0

Pash

Ohh ok sorry, you were very close to finishing the problem then. class B is 16 bits, add your six you need for subnets /22