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ddantesFlag for United States of America

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Cable Modem performance

I have a Cisco Cable Modem model 2100 (also called Scientific-Atlanta WebStar 2000)  which can connect to different computers simultaneously, by using both the USB and Ethernet ports on the modem.  With ethernet, the download and upload speeds, respectively, are 11862/954.  But with USB, these speeds are 5809/951.  I belive I'm using the latest USB driver for the modem.   Is there a way to improve the USB performance?
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John
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I recommend you put a small fast switch on the cable modem and hook up both computers by wired ethernet if you can (or one perhaps on WiFi). Either wired or wifi should perform better than USB in this situation.

.... Thinkpads_User
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Thank you for your comment.   I currently have a switch (actually, a router).  But I have not been able to isolate two networks from each other by using the AP Isolation feature on the router.  I need my office network to have ethernet and internet access, and a guest network to have only internet access.  I had hoped to connect the ethernet port of my modem to a router which serves my office LAN, and connect the USB port of the modem to a wireless router for guests to access the internet.
What you could try is a VLAN router, but that would cost more money (replacing the existing router and upgrading to one VLAN capable). You might need help setting up a VLAN as well.

Another way (since this sounds like a small setup) is to properly secure the computers on the office network so that a guest (even plugging in on a wire) could not access anything.

Yet another way is to get a wireless router, hook it up to the switch and allow it to hand out its own DHCP to guests. So that is, put guests on a completely different subnet. The cost for this is a small wireless router and that should still give you better performance than USB. This is probably the best alternative for you.

... Thinkpads_User
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User generated imageThank you.  I realize we are embarking on a somewhat tangential course from the original question.  But, if you don't mind, I would like to pursue it, and increase the point value because it is now a broader subject?   I've embedded a schematic of my office and guest network.  I think the fact that the wireless and wired routers are connected by ethernet may somehow be defeating the AP isolation feature on the wireless router.  I can see my computers with Advanced IP scan when I log on to the guest network.   I was hoping to eliminate the ethernet connection between the wired and wireless routers by using the USB port on my modem, and thereby isolate the office and guest networks.  Is there a way to implement your most recent recommendation without overhauling my network configuration?   Please note that the components of my office network have static IP addresses.  Incidentally, data on the office network is encrypted, and the LAN is password-protected.  Still, I would prefer to have these networks truly isolated.
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John
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Thank you for your comments.  I posted a detailed reply, and it disappeared after I awarded points.   I don't expect my guests to take an interest in circumventing network security, but I have an obligation to protect sensitive data in my office computers, regardless of my opinion of guests' good intentions.  There is a geographical issue, with guest quarters widely separated and intervening walls and landscaping.  I'll study the VLAN solution and invest in a modern wireless router.  Meanwhile, just one remaining question:  since the RVS4000 and the WRT5400 operate on different subnets, how can I see my office computers when I log onto the guest wireless network and scan with Advanced IP Scanner?
Thank you, and thanks for the follow up.

With respect to the advanced IP scanner, it may be restricted to a single subnet and not scan across.

I use CommView (packet sniffer) and CommView Remote Agent allows packet sniffing across subnets. But then the agent needs to be installed on the guest computer, which is not likely to happen. The best advice, then, I can give is to try it out, putting one of your own computers on the guest side and see if you can scan through.

.... Thinkpads_User
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Thank you.  I think I didn't articulate my question very well.  I am able to see my office computers when I scan from the guest wireless network.  I wanted to know how that is possible, since they are on different subnets?
Some kinds of scanners can address IP addresses on other subnets. Normally with normal software your guests should not see the other subnet. Of course, this is the value of VLANs as they provide more isolation.
.... Thinkpads_User
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Understood.  Thanks again.