Networking gurus - quick easy question

[Curio]

Yes, this is for an assignment - so I don't expect you to just give me the answer I thought I was happy with my solution, but now I'm second guessing myself...

With a subnet mask of 255.255.248.0 how many hosts can be created?

My answer is 2047, minus the 2 reserved, for a total of 2045.

If this isn't correct, can you give me some pointers?

And go easy on me....this is my first networking class

Thanks

 

[Curio]

(2^N) - 2

Where N is the number of available bits.

So, you've 8 free bits from the final octet and three from the third octet.

(2^11) - 2

2048 - 2

2046.

For the number of subnets it's pretty much the same equation:

2^N.

Ah-ha, that was my original answer. I then confused myself by converting the 11 binary bits to decimal (which is 2047) and then subtracting the 2

Stu - yeah I will. Although my career choice strictly isn't networking, I do have to take the network basics class as part of my course.

Thanks guys - off to hand this puppy in