Subnetting different length IPs

[Mokhalil82]

Hi 

I have a question about subnetting, seems like a simple one but a point I may have missed from my studies, but now in real life networking these questions are popping up. 

So If I have use the IP address of 192.168.10.0/24, now say I need 2 x /30 p2p links so out subnet those from this IP giving me, 

192.168.10.0/30

192.168.10.4/30

Some time later (days or months) I need a subnet with 6 useable IPs so I am now after a /29, so am I able to proceed from this point and help myself to 192.168.10.8/29.

And some time later I need another /30 so I now help myself to 192.168.10.16/30

In cisco I remember learning to subnet an IP  by starting with the highest number of hosts going down. But in real life when you need subnets here and there you may not be able to do that, well you could by using a different IP address but for the sake of keeping IPs similar you may not want to.

Any help will be much appreciated.

[Panos Bouras · Accepted solution]

You can use variable subnets in anyway you want as long as subnets don't overlap with each other.

Keep in mind that doing that my end up wasting addresses.

[Mokhalil82]

Thanks Panos, that puts my mind to rest for now