2 Replies Latest reply: Sep 27, 2009 11:29 PM by Conwyn RSS

    Subnetting Q?

    abkaniki

      Could someone calculate and explain this for me. I am able to start but I always miss calculate and make mistakes. I need help getting the following:

      172.17.250.105/27

      • subnet mask
      • broadcast address
      • host bit range


      Please explain. I can go this far for now


      172.17.250.105          10110010.00010001.11111010.01101001

      255.255.255.224        11111111.11111111.11111111.11100000

       

      subnet ID                    172.17.250.96

       

      Please help me with the broadcast address, host bits, subnet bits, and if you could explain how you get that...

       

      I would appreciate similar answered questions.

      ab

       

        • 1. Re: Subnetting Q?
          Conwyn

          Hi  Abkaniki

           

          Let us try another way.

           

          /32-/27 = /5   2 to the power of 5 is 32  so the sub net mask is 255.255.255.256-32 = 255.255.255.224 which you identified.

           

          So the host block is 32 so lets retrurn to 172.17.250.105

           

          If you know your 16 times table then you know 6 * 16 = 96 so 3 * 32 =96 so this subnet is 172.17.250.96

           

          So the network is 172.17.250.96 the 1st host is .97 and the broadcast is 96+32-1 = .127 and the last  host.126

           

          Regards Conwyn

          • 2. Re: Subnetting Q?
            abkaniki

            conwyn.flavell wrote:


            Hi  Abkaniki

             

            Let us try another way.

             

            /32-/27 = /5   2 to the power of 5 is 32  so the sub net mask is 255.255.255.256-32 = 255.255.255.224 which you identified.

             

            So the host block is 32 so lets retrurn to 172.17.250.105

             

            If you know your 16 times table then you know 6 * 16 = 96 so 3 * 32 =96 so this subnet is 172.17.250.96

             

            So the network is 172.17.250.96 the 1st host is .97 and the broadcast is 96+32-1 = .127 and the last  host.126

             

            Regards Conwyn

            Thanks for that Conwyn, you explained it really easy for me. I will try out a few questions, similar to this and see how I go. I guess the trick will be for me to chart down a few columns in my 10minutes of reading time before the final exam.


            Thanks again, and hope you dont mind me calling on you when Im stuck on one of such Q?