Antony Stone wrote: > On Tuesday 21 May 2002 10:47 am, Eduardo GARCIA wrote: > > > Hi, > > > > I want to built a network that allows http navigation to any host that is > > plugged on it, without any change on its configuration. This can be useful, > > for example, in a hotel, where they want to provide > > web navigation to their customers without the need to change any > > configuration, just plug & web.
> > For example my network is 1.2.3.0 and I want that a host with an IP from > > any unknown network (i. e. 10.9.8.7) can navigate. > > No way. You can't create a network which will allow a host with some > arbitrary preset IP address (and gateway, and DNS...) to come along an plug > into - for two reasons: > > 1. the client machine will try to route to the Internet through a gateway > address; if that gateway address is not correct then it won't be able to > reach anything. i have been to a hotel that has done this. all i had to do is plug in my ethernet adapter and i was on the internet. this particular adapter was not using dhcp to bind, but had my internal network's ip address, gateway and other information including dns hosts. i think they basically answered all arp requests with the mac of the gateway. they then add a specific route entry for that host in the route table so that they can route the packets back to it. looks like they used transparent proxy for all udp requests to port 53 so that they could handle name requests. > > > 2. the gateway machine has to know what addresses belong on the inside, and > what belong on the outside, so that it can route things properly. For > example, suppose I brought my laptop with a fixed address of 213.121.xxx.yyy > along to your network and plugged it in - should I be regarded as an 'inside' > address or an 'outside' address ? (Most people, unless they work in my > office, should regard this as an 'outside' address.....) i think there is one gateway for all machines. i don't think there is a concept of inside or outside here, just routing to the appropriate address. obviously, if you wanted to talk to another host, you have to know its name and have it resolve via DNS, or you would have to know its specific IP number somehow. the specialized gateway i mentioned above would have specific routes for each of the hosts connected on its network. if it cannot find a route to that host in its routing table, then it would send the packet to the next gateway. this is pretty standard ip routing. > > > > Not any host is allowed to do this, only hosts with known MACs (only > > customers in my hotel). > > Isn't it a bit inconvenient to have to ask people the MAC address of their > laptop when they check in ? I mean, I have a laptop with a built-in > ethernet port - how many people who know how to find out its mac address ? i agree here. i don't carry around my mac address. > > > Anyway, DHCP can easily handle this for you, if you can be bothered to tell > it the MAC addresses to listen to. this only works if the laptop is using dhcp. we use specific ip address at my company, so my laptop would have to be reconfigured for this environment. IT managers are not going to be happy with salespeople reconfiguring their tcp/ip settings so they can use the hotel internet connection. -- ___cliff [EMAIL PROTECTED]http://www.genwax.com/
