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If you are given the IP address can you tell me how many computers can be connected?What do you look at?

The answer is yes. This all depends on the type of IP address.That is the class it belongs to.All that is needed to be done is to subnet the given IP adress. Depending on the address given (Class A, Class B, or Class C) you can determine how many hosts are available. This is also subject to whether the address is classless or classful. If it is classful the a Class C address can have254 valid hosts, a Class B can have64,534 and a Class A can allow over16 million hosts! If the address is classless then more focus is on the subnet mask. To illustrate a quick example, if you had the subnet address255.255.255.240, you know that it is a Class C address, but the last octet has been subnetted. Converting240 into binary gives. This means that4 bits were used for subnetting (1) and four bits are left for addresses (0). If you did all the possible ranges in binary, starting with0 and working all the way til1 you see that you get16 binary instances. Knowing that you cannot use the first and last address you are left with14, and since the .240 address splits the octet down the middle, you get14 subnets and14 valid hosts

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Question added by Amgad Hamdy Mohammed Shalaby , Senior , Tokio Marine Egypt General Takaful
Date Posted: 2013/11/12
Ahmad Yassein
by Ahmad Yassein , Infrastructure Network Manager , Ministry of International Cooperation (MIC)

I always answer the "Four" big questions in order to do any subnetting homework on any given subnet mask and address:

You're given this

192.168.10.0

255.255.255.240

1- How many valid subnets?

Answer:16.

Explanation:240 is in binary, therefore,2^4=16

 

2- How many hosts per subnet?

Answer:14

Explanation:4 bits left for host addressing, therefore,2^4-2=14. (Note:2 bits must be left for host addressing that is why we subtract2 bits)

 

3- What are those valid subnets?

Answer:256-240=16. Start at16 then do the incrementing job by16.

For example,16,32,48,64,80,96,112,128,144,160,176,192,208, 224,240. (Note: You could start by subnet "Zero" if it is enabled on the router)

Explanation: These are the16 valid subnets that we just calculated in the first question but we are more curious about what are they. :)

 

4- What is the broadcast address for each subnet and what are the valid hosts?

Answer: Let's say for subnet192.168.1.64, the broadcast address is79 and valid hosts are65 through78. The same applies to all subnets.

Explanation:

 

Subnet           64

First Host      65

Last Host      78

Broadcast     79

 

As you see, this method is easier than the binary way.

 

Cheers

Please vote if it helps.

 

 

 

shadreck ngwenya
by shadreck ngwenya , Senior Auditor-ICT , City of Harare Municipality

An example is 192.168.0.0/24  means you can effectively connect 253 machines with 2 addreses reserved for the network and broadcast i.e 255.255.255.255

The answer is yes and you need to dertemine which class the IP block falls under(A,B and C).

Muhammad Usman Ali
by Muhammad Usman Ali , Network Administrator , Information Technology University, Lahore

Yes, By Subnetting and Supernetting

Paulexe NGUEDJI
by Paulexe NGUEDJI , Cybersecurity Business Unit Manager , ST DIGITAL.

Yes, of course. Depending on the CLASS on which the IP ADD belongs, then the MASK is known. My knowlege of a Classless Inter-Domain Routing (CIDR) make it easy to determine the usable IP addresses base on the Subetmask.

 

 

Mostafa Hussien
by Mostafa Hussien , Specialist , WORKEXPERIENCE

The broadcast address will be:16.10.5.255

yes. you either look at the subnet mask to determine how many bits were borrowed to the network portion and how many are left for the host portion.

Aslam Khan
by Aslam Khan , NGOS,Banking,Marketing & Home tuition. , (NIRE,Allied Bank,STATE Life Pvt Limited,SCD & H.tuition.

if subnet mask tell me according to this.

Mohammad Shuman
by Mohammad Shuman , IT System and Network Support Engineer , LibancallPlus

yes we can tell from the subnet mask

Mohammed Khursheed Ahmed
by Mohammed Khursheed Ahmed , Manager , SOLBSTEEL

Each IP Address has 2 segments

IP Address and Subnet Mask e.g. Unique Street Name (Subnet Mask) and Unique House Number (IP Address)

Once we have both - we can find how many computers can be available

Of course - Broadcast ID and NW id has to be omitted from the total numbers i.e. -2

shameem thazhathillath
by shameem thazhathillath , IT engineer , Mercedes-Benz Research and Development India under HCL Infosystems Ltd.

Subnet mask should be known to know the IP range,Subnet mask calculate ip range

Deleted user
by Deleted user

Subnet mask should be known to calculate ip range

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