Hey,
This is a topic about WHY ROUTERS suck, and why you need them.
Those of you with Linksys routers may be worse off than you thought.
Ok, first off I'd like to share my network configuration.
[Internet] <-> Firewall/NAT (m0n0wall) </-/> 10/100/1000 switch and hub (on the other interface)
With this configuration I can do a number of things (forward as many ports ans I want...with linksys you only get 10 with their domestic routers), I have an internal DNS override meaning that I can assign a domain name to any of my internal hosts (computers/aliases) for example, this computer is me.aaopwner.com which is resolved through my firewall to 10.0.0.111.
Anyone can have the same setup as me here if they have a spare computer and like 30$s if they have spare network cards laying around and an old computer.
With this network I can do ANYTHING I want in my subnet meaning internally I can make VPN's and everything with IPsec, and you cannot do that with Linksys or any other domestic router I have seen to this date.
Why do you need a router?
The answer is, you don't. In some cases companies or stores will lie to you assuming that you are allowed ONE external IP (an IP is your address on the internet). But for those of us (most of us) that only are allowed one external IP without extra charge from their ISP we need an NAT which is integrated into your router to allow connections from the internet to be forwarded to the other computers on your network. This is a confusing concept, so I have a picture :).
So if you are on the internet at blabla.com and sending a request for their website. The server will send you the website over the port it's hosting it on (assuming it's default for http 80), the information comes from the server (blabla.com) to your router, your router with ONE external IP then routes it to the correct host on the network for this port (this is where port forwarding comes in). Now you need the router, because the website only will send it to an external ip, it doesn't care about your internal computers under your router...that's your router's job, and since only one connection can be made per port, assuming the TCP port 80 is forwarding to let's say 192.168.1.19 your router will send ALL incoming connections (TCP) being made on port 80 to your external ip to the computer with the internal address 192.168.1.19.
Here's another example. Let's say you have some new hard core, high quality porno comming in the mail. The UPS man delivers it at the door in a huge box, to conceal the smuggled goods that just made their way across the mexican border. They ask for a signature from your mom, she signs for the porn and it has Jakob Thompson's name on it your mom is the NAT in this situation because she KNOWS who the package (or the porn) goes to within her house. The UPS man doesn't care, he just delivers it at your address and calls it a day.
Now that is why you need port forwarding. Because you only have 1 external ip, and the internet only sees that ip, nothing in your subnet.
Ok, here are some disadvantages about most routers that you can pick up at bestbuy. What I have seen with most routers is you get 10-20 ports they allow you to forward, you can have a range, or a single port. There are 65535 ports... you do the math. They also die quiet often, the newer ones (WRT*) have insufficient cooling and bad firmware's (even the newest current releases), and they die ALL THE TIME, and are slow.
Ok, to make things easier on me, I will describe to you guys what a router actually is.
A router is just an NAT, and DHCP server. The NAT has one job, that is to resolve internal ip's underneath your router, your own private network if you will..we call this a subnet. DHCP is the Dynamic Host Configuration Protocol, it gives people IP addresses automatically, they are dynamic... you have to configure a static internal IP manually (there are some ways you can get DHCP to assign static IP's but that would probably confuse most people so I'm not going to say lol).
So basically up there about the connection from blabla.com went to your router (where it is then resolved through the NAT so it knows who on the subnet is requesting it) then to your the host (or the client who requested it).
Big cooperations don't use routers that you pick up at stores, instead they use dedicated computers for their NAT's and DHCP servers. This has some advantages like, being able to do anything you want, being able to forward more than 10 ports (which is a big lol), configure VPN's and DNS overrides and much much more. You can also do this with a spare computer, here's a picture of my "router."
The difference between routers and switches. Ok, it's really simple, routers have an integrated NAT, and switches do not. If you have only one external IP, you cannot directly connect a switch to the internet, instead it has to go through an NAT, whether it is a spare computer, or a router. I have a switch going through my NAT, here's a picture of it. (you can see the white cord on the very left also goes into my "router").
So... That's all, if you guys got questions, I know you do. Ask them here :).. I love networking, and I will answer any question you have.
This is a topic about WHY ROUTERS suck, and why you need them.
Those of you with Linksys routers may be worse off than you thought.
Ok, first off I'd like to share my network configuration.
[Internet] <-> Firewall/NAT (m0n0wall) </-/> 10/100/1000 switch and hub (on the other interface)
With this configuration I can do a number of things (forward as many ports ans I want...with linksys you only get 10 with their domestic routers), I have an internal DNS override meaning that I can assign a domain name to any of my internal hosts (computers/aliases) for example, this computer is me.aaopwner.com which is resolved through my firewall to 10.0.0.111.
Anyone can have the same setup as me here if they have a spare computer and like 30$s if they have spare network cards laying around and an old computer.
With this network I can do ANYTHING I want in my subnet meaning internally I can make VPN's and everything with IPsec, and you cannot do that with Linksys or any other domestic router I have seen to this date.
Why do you need a router?
The answer is, you don't. In some cases companies or stores will lie to you assuming that you are allowed ONE external IP (an IP is your address on the internet). But for those of us (most of us) that only are allowed one external IP without extra charge from their ISP we need an NAT which is integrated into your router to allow connections from the internet to be forwarded to the other computers on your network. This is a confusing concept, so I have a picture :).
So if you are on the internet at blabla.com and sending a request for their website. The server will send you the website over the port it's hosting it on (assuming it's default for http 80), the information comes from the server (blabla.com) to your router, your router with ONE external IP then routes it to the correct host on the network for this port (this is where port forwarding comes in). Now you need the router, because the website only will send it to an external ip, it doesn't care about your internal computers under your router...that's your router's job, and since only one connection can be made per port, assuming the TCP port 80 is forwarding to let's say 192.168.1.19 your router will send ALL incoming connections (TCP) being made on port 80 to your external ip to the computer with the internal address 192.168.1.19.
Here's another example. Let's say you have some new hard core, high quality porno comming in the mail. The UPS man delivers it at the door in a huge box, to conceal the smuggled goods that just made their way across the mexican border. They ask for a signature from your mom, she signs for the porn and it has Jakob Thompson's name on it your mom is the NAT in this situation because she KNOWS who the package (or the porn) goes to within her house. The UPS man doesn't care, he just delivers it at your address and calls it a day.
Now that is why you need port forwarding. Because you only have 1 external ip, and the internet only sees that ip, nothing in your subnet.
Ok, here are some disadvantages about most routers that you can pick up at bestbuy. What I have seen with most routers is you get 10-20 ports they allow you to forward, you can have a range, or a single port. There are 65535 ports... you do the math. They also die quiet often, the newer ones (WRT*) have insufficient cooling and bad firmware's (even the newest current releases), and they die ALL THE TIME, and are slow.
Ok, to make things easier on me, I will describe to you guys what a router actually is.
A router is just an NAT, and DHCP server. The NAT has one job, that is to resolve internal ip's underneath your router, your own private network if you will..we call this a subnet. DHCP is the Dynamic Host Configuration Protocol, it gives people IP addresses automatically, they are dynamic... you have to configure a static internal IP manually (there are some ways you can get DHCP to assign static IP's but that would probably confuse most people so I'm not going to say lol).
So basically up there about the connection from blabla.com went to your router (where it is then resolved through the NAT so it knows who on the subnet is requesting it) then to your the host (or the client who requested it).
Big cooperations don't use routers that you pick up at stores, instead they use dedicated computers for their NAT's and DHCP servers. This has some advantages like, being able to do anything you want, being able to forward more than 10 ports (which is a big lol), configure VPN's and DNS overrides and much much more. You can also do this with a spare computer, here's a picture of my "router."
The difference between routers and switches. Ok, it's really simple, routers have an integrated NAT, and switches do not. If you have only one external IP, you cannot directly connect a switch to the internet, instead it has to go through an NAT, whether it is a spare computer, or a router. I have a switch going through my NAT, here's a picture of it. (you can see the white cord on the very left also goes into my "router").
So... That's all, if you guys got questions, I know you do. Ask them here :).. I love networking, and I will answer any question you have.
Comment