Networking - Subnetting - Discussion

Suppose a company ABC wants to develop two LANs for its different departments in the same building. For LAN network the main factors to consider are reliability, security, and speed. The company has also no cost constraints for the development of LANs.

After LAN development, this company also needs to connect these two LANs with each other and with its remote offices located in different cities.

1. Identify the suitable medium that will fulfill the requirements of the company in order to develop LANs.

2. Which type of address will be associated when data will travel from one user to another user within same LAN?
VLAN. if two people attempt to send information at the same time,

3. If the user of one LAN wants to communicate, with a remote user located in another city network then which type of address will be used?

4. Which type of networking device will be used to transfer data from one of the LANs to a remote user located in the network of another city?

Please tell me the solution.

We cannot use subnet mask 255.255.255.240 with both IP addresses as this subnet mask will take them in two different subnets(networks).

The binary equivalent of 240 is 11110000. i.e 16 is the increment.

The possible networks are:

192.168.1.0 to 192.168.1.15.
192.168.1.16 to 192.168.1.31------>192.168.1.20 belongs to here.
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192.168.1.192 to 192.168.1.207----->192.168.1.201 belongs here.
192.168.1.208 to 192.168.1.223.
192.168.1.224.

So we can clearly see that if we use subnet mask 255.255.255.240 then communication will not be possible as both will be on separate networks. So we have to use 255.255.255.0 subnet in both so that they belong to same network.

Lets say the mask is x.x.x.240.

It means we have borrowed 4 network bit from fourth octet. If you know binary it will say you can have 16(2 power 4) subnets and 14(2 power 4 - 2(Network ID AND Broadcast address)) valid hosts in each subnet.

So having said that the given IPs will not fall in any of the subnet. So here is the problem with mask, which supposed to be /24, so that we can have 8 hosts bit(2 power 8-2= 254 Valid hosts). I hope it helps everybody.

The Increment (or) Block size is 16, which means the IP Address range will be 192.168.1.0 to 192.168.15.255 if you can see the IP Addresses 192.168.1.20 & 192.168.1.201 falls in between the IP Address. Hence, the IP Address 192.168.1.20 & 192.168.1.201 having mask 255.255.255.240 can communicate.

Can anyone explain clearly why the Answer shows the Masks are different. Please Help?

I too am confused as it seems they both have the same subnet mask (x.x.x.240) while i agrees the they are different subnets eg .20 is in subnet .16 and .201 is in subnet .192 they clearly share the same subnet mask x.x.x.240 because it states it in the example and it states in the answer that the hosts have different subnet masks, maybe I am not understanding it correctly.

Nowadays, the interface card automatically detects no matter if we use straight or crossover.

255.255.255.240 - useable IP range 192.168.1.16 - 192.168.1.30 - Wrong answer.
255.255.255.192 - usable IP range 192.168.1.1 - 192.168.1.62 - Wrong Answer.
255.255.255.0 - usable IP range from 192.168.1.1 to 192.168.1.254,

Hence the answer.

First of all, the 224 is a broadcast and falls at the very last bit of the 16th time. Meaning the subnet address available there and asked for cannot be used, given that 224 is not available. The subnet is 239 also because the 240 is not available on the range when working with turns of 16 subnets.

The series is as follows:

192.168.1.0, valid host(1 to 14).
192.168.1.16, valid host(17 to 30).
192.168.1.32, valid host.
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192.168.1.192 (193 to 206).
192.168.1.208.
192.168.1.224 ().
192.168.1.240.. hence the given IP address of both host falls in different subnets.

As AND operation of IP address and Subnet mask gives us the Network address. In this case network address is different with given subnet address.

But when subnet mask (255.255.255.0) is used same network address will obtained and hence both will be on same network.

First, if you have two hosts directly connected, then you need a crossover cable. A straight-through cable won't work.

Second, the hosts have different masks, which puts them in different subnets. The easy solution is just to set both masks to 255.255.255.0 /24.