Connecting to Home Computer

  • Thread starter Thread starter JoeD
  • Start date Start date
J

JoeD

Dear Sirs,

Been having a heck of a time connecting to my home
computer from work. I have xp pro on my laptop at work.
My Pc at home xp pro also, is on a network with a
Linksys 5 port router. I have my sons computer also on
the network.
The Wan address is 68.43.94.70. I cannot even ping from
the office and a trace route goes thru about 5 hops and
gives a final message of: 192.168.196.3 reports
destination host unreachable. I have Remotely Anywhere
Software listening on a certain port and I have the port
forwarding on the router set to forward requests to my
machines IP. Still does not work...most people in the
outside World can ping my Wan address. I can also us
remotely anywhere to connect to my brothers PC for Remote
Control..from my PC at home. Not sure where the hang up
is. I have firewalls turned off. Any direction or leads
would be greatful to me. I have been battleing this one
for quite some time. If I have left anything out please
let me know or email me at (e-mail address removed). Thank
you for your time here today. Have a good one!!!

Joe
 
if you are talking about with comcast cable modems, you need to get comcast
to give your own public ip address. The ip address you see from your home
computer is not the ip address for your particular computer.
 
Thanks Mr. Cohen....Oh, My router shows the IP Address I
talked about....not sure I quite understand whats up
here. Do I need to buy my own modem instead of using
Comcasts ??? You could probably ping that ip address. If
you could clarify it would be great as I would like to
get this to work...as it should...Thanks..oh by the way,
I love your email address!!! Have a good one!!!

JJ
 
it is not a matter of your modem- it doesn't matter if you use theirs or
your own.

The issue (I believe) is that you don't have your own Public IP address.
Comcast doesn't give you your own but I have been told you can request them.

Now I don't know what effect adding an router has. Because assumably, the
router give each computer behind it its own private ip address. So I don't
know how you would do it with the router.

But I am sure if it is possible, comcast can tell you.
 
The problem is that the 192.168.x.x addresses are LOCAL only. They are not
routable (i.e., cannot transmit IP packets outside the local network).
These are "special" IP address strictly limited to your local network and
assigned by your router. Should you need Internet access from your local
network, the router will "route" your local network requests from the LAN to
the WAN using NAT (Network Address Translation), which maps the local
192.168.x.x addresses to the IP address assigned by your ISP to the router's
WAN port (e.g., 68.43.94.70). The router keeps track and manages all this
mapping among the various PC on your network. In fact, from OUTSIDE your
LAN, all traffic seems to be eminating from the SAME PC (68.43.94.70, which
*we* know is not even a PC, it's a router)! In fact, we know it could be
one of *many* PCs. The router *masks* the fact you have (possibly) multiple
PCs, and noone outside the LAN even knows what local IP addresses
(192.168.x.x) you have assigned, even if they did, they're not directly
addressable anyway, as I said, the 192.168.x.x addresses are not "routable".

All this works great UNTIL you want to access your home network from the
office. Although you know the ISP assigned IP address to your router
(68.43.94.70), the problem is, how does the router then map that address
***BACK***, in the reverse direction, to the actually assigned local IP
address of your target PC, e.g., 192.168.0.100??!! You do that by going
into the router admin interface and locating the IP forwarding configuration
page (the actual name will varying from router to router, D-Link, for
example, calls this feature "Virtual Servers"). It's pretty simple, you
just add an IP forwarding that maps the "public IP address" (the one
assigned by the ISP to the router) to an "internal IP address" (e.g.,
192.168.0.1), or whatever PC is the target. You have to add the port too,
since you can map different ports, but most of time, the ports for external
and internal mapping remain the same. Then finally, the protocols you want
to let in (TCP, UDP, or BOTH)

For example, if I had a router WAN address of 68.43.94.70, and wished to
allow public access to my home webserver on PC 192.168.0.100, port 8080, I'd
add an IP forwarding of:

Name: My Webserver
Private IP: 192.168.0.100
Public Port: 80
Private Port: 8080
Protocol: TCP

(the Public IP is assumed, of course, based on the ISP IP assignment). Now
the router knows what to do, it will redirect requests of
http://68.43.94.70:80 to http://192.168.0.100:8080

There may be other parameters too, such as limits on time of access,
usernames, etc., but the above are the basic minimums. You apply the same
principles to pcAnywhere or any other services you need access to.
Determine the ports (pcAnywhere uses 5631 for DATA, 5632 for STATUS, I
believe), the target PC IP address, and the current IP address of the
router. pcAnywhere will require two mappings, such as:

Name: pcAnywhere DATA
Private IP: 192.168.0.100
Public Port: 5631
Private Port: 5631
Protocol: BOTH

Name: pcAnywhere STATUS
Private IP: 192.168.0.100
Public Port: 5632
Private Port: 5632
Protocol: BOTH

To be honest, I don't know if pcAnywhere uses both TCP and UDP, so I
specified BOTH just to be safe and make sure it works. With some
investigation, you may find otherwise and modify the config, but BOTH will
work. Also, pcAnywhere, like other services, allows you to change the
default ports. Sometimes people do this for added security, that's up to
you (see pcAnywhere Tools->Options->Host Communcations->Advanced TCP/IP
Options).

HTH

Jim
 
For example, if I had a router WAN address of 68.43.94.70, and wished to
allow public access to my home webserver on PC 192.168.0.100, port 8080, I'd
add an IP forwarding of:
Click to expand...
Name: My Webserver
Private IP: 192.168.0.100
Public Port: 80
Private Port: 8080
Protocol: TCP
Click to expand...
(the Public IP is assumed, of course, based on the ISP IP assignment). Now
the router knows what to do, it will redirect requests of
http://68.43.94.70:80 to http://192.168.0.100:8080
Click to expand...

The cheaper routers like the Linksys BEFSR41 do not allow you to
translate the port. If you want to forward incoming request packets
designated for port 80 to your webserver on the LAN, the webserver
must be set for port 80.


--

Map Of The Vast Right Wing Conspiracy:
http://www.freewebs.com/vrwc/

You know you are in Hell when you have to make a
distinction between what is moral and what is legal.
 
Interesting, thanks, I not a fan of Linksys anyway, I had their BEFCMU10 v2
cable modem, which has a serious bug that hangs all the time. Ever since,
I've had an aversion for their product line, esp. since they did nothing to
correct it. But not providing port mapping on a routner?! Wow, how much
effort would it have taken to add this feature, 4-5 lines of code?!

Jim
 
Interesting, thanks, I not a fan of Linksys anyway, I had their BEFCMU10 v2
cable modem, which has a serious bug that hangs all the time. Ever since,
I've had an aversion for their product line, esp. since they did nothing to
correct it. But not providing port mapping on a routner?! Wow, how much
effort would it have taken to add this feature, 4-5 lines of code?!
Click to expand...

Linksys BEFSR41 is their workhorse. It is meant for the SOHO
environment. Most ISPs won't allow incoming server traffic anymore,
thanks to Microsoft buffer overruns on IIS. Port translation is a bit
sophistocated for the SOHO configuration.


--

Map Of The Vast Right Wing Conspiracy:
http://www.freewebs.com/vrwc/

You know you are in Hell when you have to make a
distinction between what is moral and what is legal.
 
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