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Consider a network of having ID as 198.128.10.10/28. There is a wifi router connected to this network and 2 mobiles and a tablet are connected to this router. Apart from these devices, 2 more desktops with 2 interfaces where these desktops are part of 2 different networks and a laptop exist in this network. How many IP addresses are still available after all the specified devices connected?

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not possible

if we subtract net id & broadcast address left with only  14 ip's and after distribution to the devices left with 10 ip's not possible
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Right. Then is it 5?
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how are you calculating, share it, more importantly elaborate the bold part in question
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Total addresses = $2^{4}$

Total subnets are 3. We can assign as $2^{3}$, $2^{2}$, $2^{1}$ number of IPs.

Total IPs used from devices = 6.

Total IPs used as network = 4

1 DBA. Therefore I got 16-6-4-1 = 5.
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i don't think subnet counting is required because it is already given in CIDR format
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But they are saying clearly two different networks.
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thats what it is bothering
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I think router along with 2 different networks causing subnetting.

Total IPused by the devices are -  1 (Wi-Fi)+2 (Mobile) +1 (Tabl) + 2 (Desktop) +1( Laptop)

= 7

Different Network exists are - Home + 2 different for Desktop = 3

so toal IP used by Host and Network are 7+3=10

Left over IP addresses are = 6

first divide it into two networks. after dividing we will have 12 useful ip addresses. among these router will take one ip. and two computers with two interfaces take 4 ip's and laptop take one ip. so we will be left with 6 ip's

See, the whole network is structured such that :

• One Laptop is connected to the main router
• Desktop D1 is connected to main router. This desktop has two interfaces and both the interfaces are connected to two different networks - only one interface is connected to THIS network.
• Similarly for desktop D2
• One Wifi router, which creates a subnet within this network. This subnet consists of the Wifi router, two mobiles and one Tablet. So, overall, this subnet will require :
• One IP address for the network main wifi router
• One IP address for each mobile
• One IP address for Tablet

So, total used IP addresses are :

• One IP address for the main router
• One IP address for Laptop
• One IP address for D1 and One IP address for D2
• Six IP addresses for the wifi subnet (Because even if there are 3 devices connected to the router, we need to allocate addresses in powers of 2)

So, total 10 IP addresses are used. Therefore, 6 IP addresses are still available.

Please correct if I am wrong.

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