Subject: From: Date:

RE: [ECS] Web access Martin Terry Thu, 29 Jun 2000 15:33:32 -0700

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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
> >

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