Networking Help

[dclamp]

I have a few questions about networks.

1. What exactly is a VLAN? I have googled several times, but i am not getting any good explanation and am getting different explanations from different sites.

2. My DHCP gives out 192.168.1.x IP's which seems that most routers give out. Is this specific to home networks? Could i change it?

3. Different Subnets? What exactly is a subnet? Why would i want to have different subnets on my network? And would my devices still work together?

I tried looking for a general Networking tutorial that would explain everything, but I couldnt find one. I figured if i wanted to learn as much as i can about networking i could take a course at my uni, which i may end up doing.

Any info would be help full

[Nightwalker83]

VLAN = Virtual Local Area Network.

[dclamp]

I know what it stands for. What does it do? How can it help me?

[TheBigB]

I'm going to post the short version. If you'd like more information on a certain topic, don't hesitate to ask.

2. The IP-address that you get from your router is configured in the router.
And yes, you can change it. This is particularly useful when chaining routers.
There are basically three IP-ranges available for home networks.
See: http://en.wikipedia.org/wiki/Private...address_spaces

3. A subnet is a network in which you can directly communicate with other devices without the need of a router. In the case of 192.168.1.XXX your subnet-mask is probably 255.255.255.0.
If you know how decimal <-> binary conversion works, I can give you a more detailed explanation, but what you basically need to know is that a '0' in a subnet-mask means that you have the full range of that byte available.
So, staying with the 192.168 range:
- A subnet-mask of 255.255.255.0 means you can have a network using IP-addresses between 192.168.1.1 and 192.168.1.254.
- A mask of 255.255.0.0 means you can have a network using IP-addresses between 192.168.0.1 and 192.168.255.254
On a side note, I always exclude x.x.x.0 and x.x.x.255 from the ranges as they have a specific role in networking.

[dclamp]

2. I will read that after this post

3. I read about subnet-masks briefly and the binary/decimal conversion. What would be the use of using 255.255.0.0 as apposed to 255.255.255.0? Simply more IP addresses? or something more complex?

[TheBigB]

Nope, it's as easy as that. More IP-addresses, that can communicate with each other directly, that is.

Basically you have 32 bits in an IPv4 address.
The 255.255.255.0 mask also is referred to as a 24bit mask, signifying that the first 24 bits are static and your network identifier.
That leaves you with 8 bits to make build a sub network with.
Can you guess the alias for 255.255.0.0?

[dclamp]

Can you guess the alias for 255.255.0.0?

16 bit? I give up