Hi Shmavis,
Re
Thanks for the reply Ralph. I believe the problems on my Mom's end have been narrowed down to the Siemens SpeedStream 5200 modem/router. I had her connect the iMac directly to the 5200 bypassing the 3com and Linksys. Still no luck. I was unable to locate the SpeedStream 5200 on the Port Forwarding site but by chance when searching google for any info on it I came across a link to Port Forwarding's site with a manual for forwarding ports on the 5200. The manual is only a few days old so maybe the link for this router just hasn't been posted on the main page yet. Anyway, after reading it and reading the static ip info I had my mom access the speedstream through the internet browser and we were able to get in there and as I read from the "manual" that I printed from Port Forwarding's site she follwed along and verified that she was seeing what I was telling her she should see(we were just looking) and port forwarding can be done from within the router/modem. But.....I am not looking forward to attemting to do this with her over the phone. Even though it is nicely laid out and does make sense to me, even though I know VERY little about all this, it will be a chore walking my mom through it.
SpeedStream 5200 At Port Forward.com
Same Typo applies as to the last setting. Should be two setting one list Port 5678 as Start and Finish and another one with start as 163845 and End 16403 on UDP.
DO it is Stages. Get her to Open the ports to her Current IP (If this is an IP issued from the SpeedStream to her computer and the 3Com is only a switch)
For this bit this page may help
http://www.ralphjohnsuk.dsl.pipex.com/page4.html#_where
Later you can talk her through the bit about putting the Modem and computer is Static modes (It's called Manually in the drop down on the Mac.
She will need to do something like this on her Mac
http://www.flickr.com/photos/90943061@N00/182655216/ After grabbing some info from her Current "Using DHCP" settings that normally shows at that drop down.
This is a Pic of a Linksys router but you can see at the third Arrow DHCP is turned Off to the LAN
http://www.flickr.com/photos/90943061@N00/92218331/ She will need to find the equivalent setting on her device (possibly in a LAN menu item).
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Re:
I have downloaded and read the user's manual for this modem/router and now wonder if simply turning off the router ability (turning on bridge mode) wouldn't be an easier solution. According to the 5200's manual this appears to be a very easy process, much easier than forwarding ports. So if I were to have her turn on the bridge mode disabling the router function would she still be required to have a static ip for both the iMac and the Windows laptop? I didn't see where the manual said this would be required. And in this situation wouldn't the Linksys then assign ip's through DCHP? Her set up would then be DSL>into 5200 set up as modem only>3com switch>out to iMac and out to Linksys WAP54G.
Ok If the Speedstream is in Bridge mode and you have two computers the other side of it on Her LAN (Local Network) they will need to be behind a device that routes.
Your earlier info inferred that the 3Com device did but you also described it as a switch.
This fact would need to be cleared up first.
If it does not route then your mothers computer would have to be behind the Linksys as well as your Dad's computer.
This Linksys may have to do the ISP login at that point.
The WAP54G Should have UPnP in the Administration tab
http://www.flickr.com/photos/90943061@N00/145187292/ which need to be Enabled. (It would not need any Port Forwarding or Port Triggering)
Check that the device has UPnP. If it does use that. If not use Port Triggering to allow both computers to log on to AIM if your dad uses AIM at all
The Linksys could then be left doing DHCP.
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RE: The NAT bit.
At present you mother does not go through the WAP54G so even if the SPeedStream and the Linksys were set up to Port Forward or Port Triggering then she herself would not be going through two lots of NAT
The Problem comes if your Dad uses any of the same ports fro any application he uses.
NAT stands for Network Address Translation.
It's the way the data gets from the ISP/Internet side to the right computer/device on the LAN (You mom's computer, the Linksys and your Dad's computer).
AT present they have two subnets.
Modem to 3com and mother's and Dad's computers
and Linksys to Dad's as a separate part.
If the WAP54G has more that one Ethernet port as well as being wireless and the 3com is just a switch then yes the 3Com can come out of the link.
The problem then might be distance and cabling
Summary.
Best set up will be SpeedStream in Bridge, Linksys in DHCP and UPnP active - with both computers connected to Linksys
Next would be ports opened on Speed stream and later made Static to Linksys Router and iMac. With or without the 3Com
(This presumes the 3Com does not route)
NOTE: With my Linksys it was possible to to give a computer an IP from a Modem but list the Linksys as the Gateway/"router" on the Mac and achieve a Partial Aceess Point only (The Linksys had to route either using DHCP or being Static it could not have this turned Off liek you may have read Airport Base Stations can)
Note 2:
Please can you separate separate bits out when you post.
It's a a personal thing of mine rather than an absolute but I do find it helps.
Other helpers here will also pick and choose which bits they can answer if you separate it out so they can quote back the bits they are dealing with.
I hope this helps.
11:37 PM Monday; February 19, 2007