| ECS-L Home Automation and Security Archives |
| Subject: From: Date: | RE: [ECS] Web access Ingo Pakleppa Thu, 29 Jun 2000 15:42:19 -0700 |
And while you are at it, also make sure that your ISP doesn't specifically prohibit running any type of server applications - that would be a particular problem for cable-modem users because their service agreements generally prohibit it. And they seem to get pretty strict about it. Ingo At 03:33 PM 6/29/00 -0700, Martin Terry wrote: >It's probably related to how your ISP defines "hosting". If they acknowledge >you can run a web or ftp site in the service agreements (which would require >a static IP) then you should be OK. > >If they don't make any such guarantees, or they specifically prohibit >hosting, then all bets are off. If you plan to operate ECS via the web >interface in this fashion, you should talk to your ISP about your service as >if you are a running web server using a non standard port. This is really >all ECS is doing. You could run on port 80 just as easily (assuming Mark >makes this user definable) - the only drawback is that you couldn't run a >standard web server on the same machine, which few people are likely to do. > > > >-----Original Message----- >From: donstephens@101freeway.com [mailto:donstephens@101freeway.com] >Sent: Thursday, June 29, 2000 2:37 PM >To: ecs-list@netbloc.com >Subject: Re: [ECS] Web access > > >Thanks Martin: > >I assume if I pay for a static IP address, I do away with the NAT at the >ISP? Then I will have to deal with the router at my house....which I have >some control over. Is this correct? > >Thanks: >Don > > >----- Original Message ----- >From: "Martin Terry" <Martin.Terry@mail.tribnet.com> >To: <ecs-list@netbloc.com> >Sent: Thursday, June 29, 2000 2:29 PM >Subject: RE: [ECS] Web access > > > > I'm not Dario, but since this is my profession I'll take a stab at a brief > > explaination. :) > > > > First off, depending on how NAT is setup, you may not be able to connect >at > > all. On the routers we manage, NAT can be inbound (meaning someone is >asking > > to connect inward, for example a web server), outbound (meaning I'm > > initiating a connection outward, for example a web browser), or > > bi-directional (meaning both of the above are true). > > > > The advantages of outbound connections is that you can map multiple >outbound > > connections to a single address, in our company as an example all 800 > > employees can be surfing the web and from the Internet's perspective they > > all appear to be coming from a single address. You couldn't tell them from > > 800 web windows on a single machine. > > > > The disadvantage is that you can't initiate an inbound connection - for > > example an employee cannot host a web site on his personal computer and > > allow people on the internet to connect - the router simple rejects these > > requests. > > > > So if your ISP doesn't allow you to host a web server, and has setup > > outbound NAT only, you are out of luck. > > > > If you have a bi-directional NAT mapping, basically it is simple a 1 to 1 > > address translation. Anything that "appears" to come from one address is > > changed to another. > > > > How can you tell where to connect to ECS? > > > > This is a tough question, because the event and batch files I've seen with > > ECS rely on the workstation finding out it's own address and then mailing > > that address to the user. For NAT (Network Address Translation) this won't > > work, because the IP address of the workstation isn't the same as what it > > appears to be to the end user, on the other side of the router. It's not > > taking the conversion into account (it can't). Here's an example: > > > > Workstation ( IP 192.168.1.1 ) Internal network address often used with >NAT. > > with web server (ECS for example) > > | > > | > > | Network 192.168.1.x > > | > > | > > Router (IP 192.168.1.2) with NAT entry for workstation 192.168.1.3 <-> > > 207.46.131.30 > > | (IP 207.46.131.1) > > | > > | Network 207.46.131.x > > | > > | > > Internet "cloud" > > | > > | > > | > > End user with browser (IP 192.18.97.195) > > > > to contact ECS the browser would have to enter http://207.46.131.30:3000 >in > > order to make the connection. This request eventually translates to a > > request to the router, which is masquerading as 207.46.131.30, and usually >a > > bunch of other addresses. The router has a table that says "if you get a > > request for 207.46.131.30, change it to 192.168.1.1". It then passes the > > data on, and it appears to come from the address 192.168.1.3. > > > > NAT can be a real problem (read not work) when the machines communicating > > pass their IP addresses in the data stream. NAT cannot see this and modify > > it appropriately, therefore several protocols will not work via NAT. > > > > > > > > > > -----Original Message----- > > From: Don [mailto:donstephens@101freeway.net] > > Sent: Thursday, June 29, 2000 9:19 AM > > To: ecs-list@netbloc.com > > Subject: Re: [ECS] Web access > > > > > > Hi Dario: > > > > Since you seem to know something about how this works, I'll ask you. I >have > > a router on my local lan that uses NAT for addressing, and I have a >dynamic > > address at my ISP, although I have a DSL line and it has never changed. >I'm > > want to access ECS from a remote computer. How do I come up with an URL >for > > ECS? > > > > Thanks: > > Don > > ----- Original Message ----- > > From: "Dario" <adpm.to@inwind.it> > > To: <ecs-list@netbloc.com> > > Sent: Thursday, June 29, 2000 7:31 AM > > Subject: Re: [ECS] Web access > > > > > > > Mark Gilmore ha scritto: > > > > > > > > Note that if another port # would be more conventional, I > > > > could easily change the default to something other than > > > 3000. > > > > > > As there's not yet a standard for home automation access via > > > WEB, I > > > guess everything is OK (IMHO) > > > Actually, if ECS is working wuite like a WEB-server, then you > > > could use > > > port 80, the standard for HTTP (so nobody would have trouble). > > > Of > > > course, provided you're not using other webservers on ECS > > > machine. > > > I've set up port 80 on my system, and I can get to it via any > > > computer. > > > > > > Dario > > >