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Local Network IPs - 10.0.0.0/8 or 192.168.0.0/16?
mike9010 asks: "After reading a few articles on the net about networking, I have come up with a question. It seems that most of them say to use 192.168.0.0/16 for a local network. Why not use 10.0.0.0/8 though? It is my understanding that it can hold a lot more IP addresses, and it is also prettier." What local network range are you using for your networks?
Use of 10/8 can be a fine choice.
chongo (was here)
No it doesn't, it insists on using 169.254.MS.BS ip addresses, especially when multiple wins servers or a lagging dhcp server is around, which goofs up everyone's networking. somehow M$ thought "ATIPA" was a good idea.... morons.
I actually asked this question once. Nobody could really give me a good answer. I personally prefer 10.0.0.0 over 192.168.0.0. It does look pretier, it's easier to type, and you do have more IPs to play with. Who has need for all those IPs is beyond me, but I say you can never have too many IPs.
It does look prettier. here is how I broke down my NAT network
10.0.0.0-255 = Routers/Server - Kinda, sorta DMZ
10.0.1.0-255 = Wired Workstations
10.0.2.0-255 = Wireless Workstations
10.0.3.0-255 = Test stuffage
192.168.0.0 is the defacto standard for just about any router you buy off the shelf. Perhaps there is a valid reason?
furthermore, DO NOT use 192.168.0.XX. Because you might get a job with a vpn-ing company that uses that to. Get a random number under 256, and use that instead of 1.
...
e.g. I use 192.168.88.XX. I used to use 192.168.1.XX, but guess what, I got a job
The one most often used by home networking products is 192.168.1.x in my experience, not the full
RFC 1918 recommends that you choose a network randomly in order to reduce the chances of colliding with any other internal network you may ever want to connect to.
APIPA is Windows way of doing "dhcp-less dhcp" for "fast" networks, where there's no DHCP server. I.e. a quick meeting workgroup. with no external network connection.
All the services will work over APIPA fine...file sharing, etc. just no central server is required to do it.
Though honestly, you could use whatever you wanted with the proper network setup. After all, if the stuff isn't visible to the rest of the world, then it doesn't matter what you use. Worst case scenerio is that you might stumble upon a computer in the real world with the same IP address as you, but that'd be rare. It might not even be a problem if you accessed it by a DNS entry through a DNS server that was external to your network, but I can't say that for sure.
You're wrong. How the computer obtains the IP address is irrelevant. When it attempts to send a packet to that IP address, it will be routed to the computer with that address on the private network rather than the one in the real world.
Disabling Auto IP-address generation
192.168.0.0/16 doesn't exist.
It's really a set of 256 (254, really because you aren't supposed to use 0 or 255)
192.168.1.0/24
192.168.2.0/24
192.168.3.0/24
192.168.254.0/24
Now, if you set up your internal routing and gateways correctly, the difference doesn't matter, but TECHNICALLY, since 192 starts with the binary digits '110', it's a class C (/24) network.
FYI.
Which (10.0.0.0/8 or 192.168.0.0/24) you use doesn't matter unless you need to connect your network to somebody else's, but a bad decision (or evaluation of capacity) early on can come back to create problems if your network grows beyond the address space you planned for it. GOOD DESIGN IS ESSENTIAL to preventing problems down the road. Usually the # of hosts you need on your network segments drives the decision. Some larger networks will use the
I'd recommend searching Cisco's site for white papers on network design, or maybe googling for TCP/IP tutorials.
"Lawyers are for sucks."
- Doug McKenzie
It is a method of indicating how many bits in the address are part of the 'network' number, as opposed to the 'host' number. For example..
/24 means the user has 254 hosts at their disposal, while a /8 means over 16 million.
In 10.0.0.0/8 that means there are 8 bits that identify the network (10.x.x.x) and 24 bits (IP addresses are 32 bits, 8 bits are already used for network; 32-8=24) for the machine number (the x.15.53.45)
So now, for '192.168.0.0/16'. The 192.168 part is the network part, and the '/16' means the last 16 bits are used for hosts. When the slash-number is larger, that means the person with that IP range has less IPs.
I really hope this helps, sorry I'm not the greatest at explaining things.
:wq
It's to seperate the bitmask. An IPv4 address is 32 bits long, in big endian order (biggest value goes first, like our decimal system). The /XX is simply an abbreviated way of writing a subnet that starts with n 1's and ends with 32-n 0's. For instance, 10.0.0.0/8 means the 10.x.x.x network with a subnet mask of 255.0.0.0. 192.168.0.0/16 means the 192.168.x.x network with a subnet mask of 255.255.0.0. 192.168.123.128/26 means the 192.168.123.[128 to 192] network, with a subnet mask of 255.255.255.64.
Almost always, if written in binary, subnets will look like a bunch of ones, then a bunch of zeros. Sometimes, it's convenient to have a subnet that does *NOT* designate a contiguous network segment. For instance, you might have 192.168.2.[64 to 127] and 192.168.3.[64 to 95]. In this case, this is a network 192.168.[2-3].[64-95] with a subnet mask of 255.255.253.32 (which can't be represented in the / form). Don't try this though, as certain buggy OS's might get confused.
He who laughs last is stuck in a time dilation bubble.
192.168.0.0/16 certainly does exist. The first three bits has not dictated the netmask for years. See RFC1817 for more information on this. Here's a relevant excerpt (emphasis added):
That's exactly it.
;-) But you get the idea. I have seen a /24 fill up which was a huge pain so I use a /16 for the dhcp range. I will never ever run out of IP's.
Here at my company I use the 10/8 wherever I can.
Set it up something like this
10.0.0.0 = IT
10.0.1.0 = dhcp range
10.1.0.0 = IT at a different site
10.1.1.0 = dhcp range 2nd site
10.4.0.0 = test systems
10.5.0.0 = production nat
The ranges have been changed to protect the weak
There's a couple of 192.168 network scattered about, but this makes things really easy.
I do use the 192.168.0.* range on my home LAN though.
/* oops I accidentally made a comment, sorry */
Hopefully you don't try to access Los Alamos hosted Web Sites. http://ws.arin.net/cgi-bin/whois.pl?queryinput=192 .16.42.0
If you can't figure out my address, just drop me an e-mail and I will explain.
These are not BS. This was an IP block set aside for future use and Apple, MS, Sun, and others decided to use it for local link zero config stuff. This was codified by the ietf and is specified in RFC 3330 and other places.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
CIDR, an acronym for Classless Inter-Domain Routing makes this irrelevant.
Oh yes, and an Everything2 Node for your reading pleasure.
Chris Benard
The correct answer to this question is RTFM. If you have to ask this question, you're not competent to plan out a large network.
Now granted this limits me to 256 IP's
/16 instead of /24? Considering that the 172.(16-32).x.x addresses are all /16's anyway.
So if you're concerned about that, why not just change the mask to
honestly, you could use whatever you wanted with the proper network setup.
Please, PLEASE, PLEASE, never do any network setup. Ever. Until such time as you understand what you're talking about.
Worst case scenerio is that you might stumble upon a computer in the real world with the same IP address as you, but that'd be rare.
Depending on the range, "rare" is pretty subjective.
It's not the specific IP address, but the whole network. When you take an IP address belonging to someone else, you are not only limiting yourself from talking to that one IP address, but you're limiting yourself from talking to every computer on that IP network.
It might not even be a problem if you accessed it by a DNS entry through a DNS server that was external to your network
Before giving out advice, please learn a little bit about IP. DNS means NOTHING .