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Help... how do I figure this sub problem.

SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
I got the subnetting basics down but can't put it together to solve this, thank you.

Network ID: 213 214 150 0
Subnets Required: 13

What is the subnet mask?

1st Available Host
Address of Subnet 1?

Max # of hosts/subnet?

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    miller811miller811 Member Posts: 897
    The IP scheme that they gave you was a single subnet with 254 hosts possible. It is a Class C address which is a /24 or 255.255.255.0

    Class C Range 192 - 223 in the first octet

    it could be broken into two segments of 128 bits by changing the mask to a /25 = 126 usable hosts per subnet
    it could also be broken into 4 subnets of 64 bits by changing the mask to a /26 mask = 62 usable host/subnet
    it could also be broken into 8 subnets of 32 bits with a /27 mask = 30 usable hosts/subnet
    it could also be broken into 16 subnets of 16 bits with a /28 mask = 14 usable hosts
    it could also be broken into 32 subnets of 8 bits with a /29 mask = 6 usable hosts
    it could also be broken into 64 subnets of 4 bits with a /30 mask = 2 usable hosts

    That should be enough to get you started....
    I don't claim to be an expert, but I sure would like to become one someday.

    Quest for 11K pages read in 2011
    Page Count total to date - 1283
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    phoeneousphoeneous Member Posts: 2,333 ■■■■■■■□□□
    Start by asking yourself:

    "How many binary bits make up 13?"
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    Haruna Umar AdogaHaruna Umar Adoga Member Posts: 24 ■□□□□□□□□□
    The given network (213.214.150.0) should be subnetted to meet the requirements of 13 hosts right ?
    First you have to know that the above address is a class c address which also means that it has a subnet mask of 255.255.255.0.
    Then you can use the block size method of solving the problem (VLSM)
    with your powers of 2 block sizes,
    i.e 128 64 32 16 8 4 2 1 = 255 (for all ones)

    from the above block sizes, its obvious that to meet the requirements of 13 hosts, you will need to use a block size of 16 which means that the first 4 bits will be ON (borrowed or added to your given subnet mask which is /24 in this case)

    Therefore, using a block size of 16 gives us a new subnet mask of /28 i.e 255.255.255.240 (adding 4 bits to the given mask of /24) which will meet the above requirements of 13 hosts

    since 4 bits were borrowed (added), it implies that :
    number of subnets = 2^4 = 16
    number of valid hosts/subnet = 2^4 - 2 = 16-2 = 14 hosts per subnet.

    your subnets are :
    (213.214.150.0 to 213.214.150.150) i.e first subnet

    (213.214.150.16 to 213.214.150.31) 2nd subnet

    (213.214.150.32 to 213.214.150.47) 3rd subnet

    . . . and so on.

    which means that the first valid host on the first subnet is :
    213.214.150.1 with a broadcast address of 213.214.150.15 and a subnet mask of /28 (255.255.255.0)

    and max # of hosts/ subnet = 14.

    Hope you get to understand this method.
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    Thank you all, I will dissect the info and learn.
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    tech-airmantech-airman Member Posts: 953
    I got the subnetting basics down but can't put it together to solve this, thank you.

    Network ID: 213 214 150 0
    Subnets Required: 13

    What is the subnet mask?

    1st Available Host
    Address of Subnet 1?

    Max # of hosts/subnet?

    SurferdudeHB,

    What class is the network address?
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    SurferdudeHB,

    What class is the network address?

    Class C
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    miller811miller811 Member Posts: 897
    did it click for you yet Surferdude?
    I don't claim to be an expert, but I sure would like to become one someday.

    Quest for 11K pages read in 2011
    Page Count total to date - 1283
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    tech-airmantech-airman Member Posts: 953
    Class C

    SurferdudeHB,

    What is the default mask for a Class C network?
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    surferdudehb,

    what is the default mask for a class c network?

    255.255.255.0
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    miller811 wrote: »
    did it click for you yet Surferdude?

    Starting to, going to do another problem.
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    mella060mella060 Member Posts: 198 ■■■□□□□□□□
    I got the subnetting basics down but can't put it together to solve this, thank you.

    Network ID: 213 214 150 0
    Subnets Required: 13

    What is the subnet mask?

    Max # of hosts/subnet?

    hmmm lets see...this is a class C address so the default subnet mask is 255.255.255.0

    You require 13 subnets right ? So then what power of 2 will give you the required amount of subnets ?

    2^3 will only give you 8 subnets...2^4 will give you 16 subnets...so then you require 4 subnet bits.

    So your subnet mask would be 255.255.255.240 /28...does that sound alright ?

    That leaves you with 4 host bits so 2^4-2 = 14 hosts per subnet
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    Ok I think I got it guys. I reviewed my CBT Nuggets videos and can now put it all together. Thank you all! :)
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    tech-airmantech-airman Member Posts: 953
    255.255.255.0

    SurferdudeHB,

    If you borrowed 1 subnet bit, how many subnets can you have?
    Does it meet the design requirement of "Subnets Required: 13?"
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    SurferdudeHBSurferdudeHB Member Posts: 199 ■■■□□□□□□□
    SurferdudeHB,

    If you borrowed 1 subnet bit, how many subnets can you have?
    Does it meet the design requirement of "Subnets Required: 13?"

    No you need to borrow 4 bits.
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