Running two machines off one connection:hardware&setup

www.practicallynetworked.com/sharing/sharing.htm
http://www.annoyances.org/exec/show/ics

I'm using pppoe with an external ADSL modem. Does that help?

the easiest way is to get a router. I use a d-link 704 (about $80 US) Linksys also makes a good one

is a router the same as a hub?

is a router the same as a switch?

Routers are designed to connect LANS.

Hubs forward all packets between LAN segments.

Switchs  are designed to filter and foward packets between LAN segments.

Many routers also come with switches as well as acting as firewalls.

Sorry, I overread that the second laptop runs Linux. For Linux, you can use Squid (should already be on it) as a HTTP/HTTPS proxy. For other protocols and for firewalling, there is a whole range of free software out there, so I won't elaborate on that topic unless you can't find that information yourself.

--g.

why do I need at least 4 ports?

4 ports: laptop #1, laptop #2, ADSL modem, one spare port...

:-)

to bad the answer is wrong. A hub, connected to the modem will not allow both machines to access the internet at the same time, unless your isp will assign you two ip addresses. a hub can not do dhcp or NAT. If the questioner had bothered to follow the links provided, they would have found the correct solution.

Concur w/ stevenlewis > hmmmmmm bad for the PAQ huh steve?

Yup, I hate that answer button. I wish they would remove it altogether

After review of this question, it appears the answer accepted does not answer the question.  To anyone who reads this question, refer to posts by stevenlewis for the answer.

stevenlewis, look for your question in this topic area reflecting your correct response to this question.

Computer101
E-E Moderator

Thanks C101. I am more concerned that the questioner will have to come back now to get his network working (simultaneous internet access for both machines).
for any one purchasing this question
the modem must be connected to one of the machines, this machine must be connected to the hub, and the other machine must be connected to the hub. the machine with the adsl modem will need two NIC's. then this machine (if the xp box, using ICS) can provide the necessary NAT (network address translation).
The links I provided above will give step by step instructions
or the alternative, get an inexpensive gateway/router, hook both up to the LAN side, the modem to the WAN side, set up the router (with username and password info), set up the NIC's with the correct ip info (or set them to use dhcp, if the router provides it) and your good to go



gandalf94305 In the future, please submit as comments. While that answer button is still (we have tried to get it removed) here, we don't use it, as it locks the question, move the question out of the "waitng answer" area, and a lot of experts will not comment on it. It also forces the questioner to reject the answer in order to get back the "accept comment as answer" button. Here is my standard reply to new experts who post as answer

Welcome to E-E! Its common courtesy to provide comments unless you know your answer is the only answer and is 300% correct and is what the questioner is looking for and will fix their problem. Please don’t take this personally, (others could let you know before I and not so diplomatically) I made the same mistake when I first arrived and someone was nice enough to point it out to me (It hurt my feelings, but I soon realized its teamwork that’s used here). This accomplishes a couple of things: First: it doesn't lock the question allowing more exposure to other experts allowing a faster fix (many problems require an interactive dialogue to troubleshoot them properly), Secondly: it gives the questioner the option to make an award based on the best comment that helped the most in fixing their problem and it is also is common courtesy to other experts.  Again welcome and look forward to working with you in the future, a lot of teamwork is used at this forum, as you will see! :>)  Quote shamelessly stolen from Dave, Thanks again Dave

Your answer may be correct, and I hope it is, after all the main goal here is to help the questioner, but when you propose an answer it removes the "accept comment as answer" button thereby robbing the questioner of the choice to choose which expert helped the most. If your comment is chosen by the questioner, you will be awarded the points.
Thank you  
Steve  

Hi,

stevenlewis:

 For 500 points I expect wayyy more than "follow the links provided..". If you put as much effort into answering the original question as you did into reporting a flaw in the accepted answer, then there would certainly have been no problem. You rightly care about the PAQ but it's pretty dumb to suggest that it's my fault for not studying the links - if I had time to learn about the subject I of course wouldn't have asked here in the first place. If it's more important to you to create the database than to help the questioner, then you should consider spending more of your time on a site which is more geared towards databases.

Moderators:

I also think it beggars belief that the moderators are prepared to award you points (hopefully not from my account) while the only thing stevenlewis provided was links (which although they may answer the question, certainly provide an enormous amount of redundant information to sift through - should I get points by referring someone to google?) and saying that part, only part of the answer which I accepted was wrong. Under any reasonable definition, from a questioners point of view,
stevenlewis didnt answer the question. I learned way more from the answer I accepted, even though it apparently contained a mistake. Please take note.

Note taken and thank you.  The points did not come from your account

Computer101
E-E Moderator

https://www.experts-exchange.com/jsp/qManageQuestion.jsp?qid=20323866

Ok all, here is what I have done.  One, reduced the points in the question to 166.  Therefore, the answer accepted gets that.  Second, I posted a question for stevenlewis and will reduce that to 166.  Third, I have made a question for bittwiddler in this topic area for 166 points.  

Question resolved, all taken care of.  No response needed in this thread.

Computer101
E-E Moderator

Please take note, if you followed the "accepted answer", then your network would not work as you had hoped. I thought you were interested in a solution, not an education. I posted those links, rather than re-invent the wheel. That doesn't make the info any less relevant or correct. I feel points, and answers should be awarded on correctness, not effort. As far as your reply about the router, I was at work, and didn't get back to this Q until later.

"and saying that part, only part of the answer which I accepted was wrong."
True, but this is a key part, the base of the solution. If it was merely a typo, or a slightly incorrect ip info, that would be one thing, but since this is the base on which the solution lies, it becomes more important
You of course are free to accept which ever you wish (it's your question). I really don't care or need the points (check my profile), but I do care about the PAQ being purchased with wrong info, and I do care that the answer button was used. In all my 1707 accepted answers, I used the answer button once, and regretted it.
I do hope you got the info you were looking for, and I hope your network performs as you need it.
And the points didn't come out of your account.
Good luck to you
Steve

Oooops, sorry C101, I was typing while you were responding

I was interested in a solution *and* an education! But there's no reason that you should have known that .. as you suggested 500 points means different things to different people.

I'm extremely glad you pointed out that there was a problem in the answer. Being the cautious, double-checking type I don't think I would have have ended up with the wrong piece of equipment, but I might have, so thanks.

Basically I'm grateful for your contribution in this question, I believe you're a real expert and I believe you know the answer. I also would have liked to have more of a discussion after gandalfs answer, and I understand the points you are making about the answer button, although I think it's the system which fundamentally needs changing and I don't blame gandalf for using it.


"If the questioner had bothered to follow the links provided, they would have found the correct solution."

this is of course what I objected to - I felt, among other things, you were demanding rather too much of me as the  questioner. However, I made my point in the above post, so all is forgiven.

Glad that you feel this way, and I look forward to responding to your questions in the future.
I hope this hasn't soured your on EE, in my opinion the best tech advice site on the net (I may be biased here LOL)

"Thanks C101. I am more concerned that the questioner will have to come back now to get his network working (simultaneous internet access for both machines).
                       for any one purchasing this question
                       the modem must be connected to one of the machines, this machine must be connected to the hub, and the other machine must be connected to the hub. the machine with the adsl modem will need two NIC's. then
                       this machine (if the xp box, using ICS) can provide the necessary NAT (network address translation).
                       The links I provided above will give step by step instructions
                       or the alternative, get an inexpensive gateway/router, hook both up to the LAN side, the modem to the WAN side, set up the router (with username and password info), set up the NIC's with the correct ip info (or
                       set them to use dhcp, if the router provides it) and your good to go"


Please let me see if I understand this.

Yous are saying that one of my machines needs two NIC's *if I try to use a hub*, but if I use a router, which is different from a hub, then it will be possible without adding any hardware to either of my machines (each of which already has an NIC).

true or false.. ?

Glad to see that 'communication' works here :)

True.
If going with a hub, then you need to have two NIC's on one machine (the one that will provide NAT)
If going with a gateway/router, such as Linksys or D-Link
then you only need one NIC per machine (the router will provide the NAT, adn in the case of both the Linksys and D-Link, dhcp)

I will try to draw this in ascii (sometimes the formatting here messes it up)


             Modem
                |
                |
               NIC
                |
            host machine--NIC ---hub --- NIC --client machine




             Modem
                |
                |
            gateway/router
                   / \
                  /   \
                 /     \
               NIC    NIC
                |      |
            machine   machine

I bought a D-Link d-704P residential gateway
with four LAN port switch, WAN side (for the modem)
provides dhcp, NAT, firewall, dmz for about $60 US

here is an example
http://www.tigerdirect.com/applications/SearchTools/item-Details.asp?sku=D700-2050%20P

here are more
http://www.tigerdirect.com/applications/category/category_slc.asp?id=1601

Clear as crystal.

I didn't think I would feel ready to buy equipment so soon.

Thank you

Clear as crystal.

I didn't think I would feel ready to buy equipment so soon.

Thank you

Glad to help out. Now this question is worth buying in PAQ LOL

Life is good

C101

Ok folks, I promise not to post "answers" but "comments" in the future...

Next: the answer is correct, in fact, I use this at home myself. The point is not using a hub to connect both machines to the Internet, only one will be connected at a time. If you had read my response carefully, you would have noticed the word "proxy" in there. Only one machine will connect to the Internet (which one does not matter), the other will use the one connected as a proxy for all services. We do NOT need NAT or DHCP or any other funny stuff in that case.

I have this situation every day, when either my wife or I actually connect via ADSL. Whoever comes first will get the direct link. This laptop runs a firewall and the proxy I gave. The other person will then use that connected machine as a proxy. You will NOT need two Ethernet cards. In fact, the trick with the hub is that BOTH laptops have the facility to connect directly to the ADSL modem *AND* talk to each other over the same Ethernet card.

Therefore, I really do not see your problem with this answer. Please clarify.

Cheers,
--gandalf.

so Gandalf in your opinion which solution should I use ..

is the hub method cheaper than the router method?

do I take a performance hit either way?

is either way more difficult to set up or more likely to run into trouble with small deviations from normal in ADSL software?


If I understand correctly, the misunderstanding is my fault. In the question I said
"What additional hardware do I need in order to be able to connect simultaneously to the web on both machines?"

you could interpret that to suggest that I didn't want a proxy. However, gandalf correctly spotted that I am basically a lamer and was being careless with my terms ..



Is that a correct interpretation of the situation?

gandalf. I don't see how that will work, unless your isp is assigning two ip addresses and you are using NetBEUI
when the first machine logs on, it gets it's ip assigned by your isp (using dhcp)then when the second one logs on, what is it's ip address? How does it know where it's gateway is? One time it's gateway is the adsl modem, the next it's the proxy server. It has to know this.
on you machines from a prompt type
ipconfig /all |more and check the ip info
Did you statically assign ip addresses? If not, then it has to be using dhcp. If you statically assigned ip addresses, then your proxy server has to be using NAT, as private ip addresses can not be routed to the internet.
Does your isp give you a static ip address? Note that glebspy is using PPPoE, which 95% of the time means they are getting a dynamic ip address from their isp
For info purposes, please post your ip scheme here, as I am really interested to see how this works (and learn something, maybe you can teach an old dog some new tricks)
Also what OS's are you using? and what brand hub?

Another question, I interprit it that you have 2 proxy servers, how does each machine know when it will be the proxy server, and when it will be a client?

Many questions... let me first assert that this configuration actually works because nothing else is in use here at my home in this very moment.

- I don't care what brand the hub is. Grab a cheap 10 MBit/s hub with four ports. You won't need more speed. That also answers the performance question. At speeds below 10 Mbit/s, you won't really notice a difference between a router or a hub.

- OS: I don't care. PPPoE is available for Linux and Win2k/WinNT.

- The solution I suggested does not use NAT, and does not use DHCP except in conjunction with PPPoE address assignment.

Ok. Some details: assume, each machine has its own static IP address, e.g., from the 10.x.x.x range or any other private range not routed on the Internet. This way, the two machines will be able to communicate via TCP/IP over the hub. That's what hubs are good for. In particular, if you would like to share files, access web services, etc. each machine will be able to connect to the other one as long as firewall settings on each machine permit these connections. [Personally, I use my laptop at home with the regular IP address from the company network. I don't change to a private IP range. Naturally, the other system also has an internal IP address in the company network range.]

Now you install on both machines PPPoE. PPPoE normally works with DHCP for dynamic address assignment. Linux, WinNT and Win2k don't have any problems getting a new IP address on the virtual PPPoE interface for ADSL, so if and when one of the machines does connect to the Internet, it will get a new, official IP address via DHCP from the ISP and be able to use it for direct communication with Internet sites. So far, so good.

Remember, the other machine is still connected to the hub, i.e., it can still use its local, static IP address to talk to the Internet-connected machine. And that's exactly what we will do: point your browser to the proxy on the Internet-connected machine and there you go! With a proxy set, DNS resolution will be performed on the proxy server, so the other client(s) need not go to the Internet for DNS lookups. Applications like iMesh may use the SOCKS5 server on the Internet-connected system to go to some places on the Internet. You can even route FTP/Telnet directly through, either through the SOCKS5 gateway, or through FTP/Telnet proxies.

Alternatively, you may use a router connecting to the Internet, doing NAT. However, this either requires you to get two distinct IP addresses from your provider, for simultaneous use on that single ADSL link, or to use NAT. NAT has some drawbacks with protocols embedding addresses in packets and call-back connections.

Therefore, in my opinion the hub-solution is the easiest and cheapest to set up, all components with exception of the hub itself are free, no double NICs are needed... If course, you will have to MANUALLY switch your proxy config in the browser and possibly other applications, which is not necessary with a router.

Personally, I believe the router solution is the more elegant, however, NAT may not work 100% for your applications, and a router is more expensive than a simple hub. Performance will not be an issue at ADSL speed. If you like, you can even download one of these standalone Linux routers (e.g., based on Coyote Linux) to setup a very old PC as an ADSL router. Have a look at http://www.linuxrouter.org/ or http://www.coyotelinux.com/ for more information.

As for the question "is either way more difficult to set up or more likely to run into trouble with small deviations from normal in ADSL software?", the router configuration is easy to set up, however, NAT may have to be configured and troubleshooting is not trivial. The hub configuration is basically the same, except that one machine has to perform the actual connection setup and users on the other have to point their browser to use a proxy.

Q: "What additional hardware do I need in order to be able to connect simultaneously to the web on both machines?"

I did read "connect to the web", not "generally connect to the Internet". This is the classical situation where you would use a proxy. If you have a good reason not to use a proxy, the router approach may suit you better.

Cheers,
--gandalf.

so you manually change the browser on each machine, to point it to the proxy server, each time the other one gets on first? and your other apps too?
I can see how it works now, thank you, but as far as the easiest, I would have to again disagree
with my router, I can configure it to do port forwarding, open ports for special apps, but most will open the outgoing port, and the respond to packets recieved on that port (if it requested them). And I only had to configure it once. For someone not familiar with networking, your way requires lots of manual configuration each time a different machine logs on first, with the router it's once and go
I bought a 4 port switch for $25 US (used it with ICS, and don't use any more), and my router for about $60 US, the extra expense IMHO is worth it instead of having to try and teach my wife how to configure browsers and apps to point to the proxy server depending on if she gets on first or I do
wouldn't your way get rather cumbersome with more machines on the network?

This is now suitable for more than two machines. As I pointed out, the router approach certainly is more elegant. However, pricing of approved routers depends on the country you're in... Other than that, switching proxy configurations is something I am doing all the time, so this is just a matter of habits. I run my laptop in the company, at home (direct/indirect connection to the Internet), in customer networks, ... every time with a different proxy setting. Normally, it really is just the browser you have to modify, not many other applications. If so, I agree with you: a router would be easier to handle. However, router configuration beyond pre-installed basics is also not that easy, esp. with applications using dynamic port assignments.

Ah, before we get into religious issues we should conclude that this thread has now covered the topic in large detail... :-)

Cheers,
--gandalf.