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-   -   How can I find out if there's a router? (http://www.daniweb.com/forums/thread152905.html)

OlyComputers Nov 11th, 2008 7:10 pm
Re: How can I find out if there's a router?
 
DHCP IS what translates trafic between one network to another, and what allows two unrelated networks to interface via WAN.

Yes you can establish if you have a router or switch just by looking at the devices. They WILL have model numbers you can look up on google, if not an actual reference to what the device is (WRT350N Wireless router: It's a residential example but some hardware does specify purpose that clearly.)

You can definitely call the company that set up the router. I keep records of all the hardware I install fora client, and usually remember what they have (but I have a freakish memory and a small customer base). If the sold and installed the hardware they'll know exactly what you have, if they just installed it they'll probably have an idea. It can't hurt to ask.

I COMPLETELY LOST TRACK OF THIS POST. Somehow all the notifications got spammed, so I'm sorry if I'm too late to be of any help.

jbennet Nov 11th, 2008 8:38 pm
Re: How can I find out if there's a router?
 
Quote:

DHCP IS a) what translates trafic between one network to another, and b) what allows two unrelated networks to interface via WAN.
No. Thats total crap. A) is called NAT and b) is called a gateway

OlyComputers Nov 11th, 2008 10:12 pm
Re: How can I find out if there's a router?
 
Seriously, DHCP is a component (usually the primary component) of NAT. NAT is a general term describing the translation between a WAN IP and Local IP in IPV4 (not needed in IPV6). DHCP assigns IP address to local machines providing the IP addresses involved in the translation.

A Gateway is any device that connect your LAN to a WAN. Gateways are usually a router (not always) but always something that Handles NAT. Again... NAT needs DHCP to operate unless there is another protocol, that I don't know about, that allows a NAT device to direct packets from WAN to the proper point on your LAN.

Back something up for !@#$ sake. If we're all wrong tell us what protocol we think we're talking about, if I'm misinformed about the topic I'm more than happy to be corrected but "No", "rubbish" and "crap" aren't corrections and certainly not appropriate posts for a moderator.

jbennet Nov 12th, 2008 11:31 am
Re: How can I find out if there's a router?
 
Quote:

A Gateway is any device that connect your LAN to a WAN. Gateways are usually a router (not always) but always something that Handles NAT
You can have gateways which dont do NAT, but they are essentially bridges

OlyComputers Nov 12th, 2008 3:26 pm
Re: How can I find out if there's a router?
 
I'll give you that one, I was thinking about this from a desktop perspective where whatever is shown as the "gateway" is handling NAT to the device. But your NAT device can have a gateway too (and usually does)

I'm sure Jbennet knows what I'm talking about, but for anybody who's confused imagine a group of desktops, connected to a router, connected to a DSL modem. The Router would show as the "gateway" if you did an IP config from a PC, but the modem is the gateway for the router itself.

jbennet Nov 12th, 2008 5:10 pm
Re: How can I find out if there's a router?
 
yeah in fact the modem in your example is both a gateway/bridge as it provides translation services as well as providing a physical bridge betwee media and transports of distinct types (e.g ethernet with TCP/IP and coaxial cable using something like DOCSIS)

Quote:

The Router would show as the "gateway" if you did an IP config from a PC, but the modem is the gateway for the router itself
you are confusing your terms. The term "default gateway" with relation to TCP/IP and DHCP is not nececerially the same thing as the term "gateway" with relation to network maps and hardware

OlyComputers Nov 12th, 2008 6:08 pm
Re: How can I find out if there's a router?
 
That's exactly the point I was making. On a network with that layout there are acutually multiple gateways. A server that shares internet access to a network is just as much a gateway as the modem that connects the server to the WAN.

I'm not sure a standard DSL/Cable modem actually handles NAT. Since it's unable to assign local IPs, it simply allows the device connected to it to use it's IP. If you have a PC directly connected to a modem and run IPconfig it will show your public IP.

NAT has become a pretty generic term, and I'm not sure if simply directing your WAN IP to a PC counts, but I was under the impression that you had to create a new IP range to count as NAT.

Stylish Nov 13th, 2008 12:38 am
Re: How can I find out if there's a router?
 
1) NAT (Network Address Translation) works regardless of DHCP. It TRANSLATES, not ASSIGNS.

Quote:

Originally Posted by Wikipedia
In computer networking, network address translation (NAT) is the process of modifying network address information in datagram packet headers while in transit across a traffic routing device for the purpose of remapping a given address space into another.

Not sure I really have to go into more detail. (please note the lack of "assign", "providing addresses" or "responding to dhcp requests"). Now, NAT vs IP masquerading - those two are a bit harder to distinguish between.

2) DHCP is a dynamic configuration protocol. It has jack to do with NAT, IP forwarding, masquerading, etc, etc and so on. It does help assign DNS servers and a Gateway if one should be used.

Just so we are clear..
Quote:

Originally Posted by OlyComputers
I'm not sure a standard DSL/Cable modem actually handles NAT. Since it's unable to assign local IPs, [...]

NAT != assigning IP addresses
DHCP != routing or anything to do with packet advancement, reversement, traversement or enjoyment.

Let's not even get started on Gateways..

OlyComputers Nov 13th, 2008 4:26 am
Re: How can I find out if there's a router?
 
I"m still not sure which a standard modem actually does. It doesn't so much "assign" an ip address as just lends it's own IP adress to the one device connected. A serial dial-up modem certainly doesn't assign an IP adress, so I don't think that a single IP DSL modem does either (maybe you got your definitions backwards)?

Thank you very much stylish. I skimmed the wikipedia pages once I started feeling unclear on the terms. But DHCP is (also?) a protocol for assigning IP adresses, as stated on the same wikipedia page you quoted. at least in MY use, the main thing I do with DHCP is to allocate IPs.

I don't think I ever said NAT NEEDED DHCP, just that DHCP was a component (that can be bypassed by other means of assignment.) but I did misspeak in post #11 when I said DHCP translates the information, I meant that it provides destinations for the information to be directed to.

This post really has just gotten mixed up...but I think the information Sonya needs was covered, I hope you were able to sort through everything and receive an answer to your question. If we didn't tell us what you're still unsure about and we'll try to give you a more...focused answer.

jbennet Nov 13th, 2008 10:59 am
Re: How can I find out if there's a router?
 
Quote:

I'm not sure a standard DSL/Cable modem actually handles NAT. Since it's unable to assign local IPs, it simply allows the device connected to it to use it's IP. If you have a PC directly connected to a modem and run IPconfig it will show your public IP.
Wrong. My ISP-provided cable modem acts as a DHCP server and performs NAT. The machine connected to it gets assigned 192.168.1.2, the modems internal IP is 192.168.1.1


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