When connecting individually Power Macintosh G3 with 10Base-TX and iMac G3/333 with 100Base-TX to 3Com Cable Modem CMX they work. If Cable Modem is connect to Farallon Dual Speed Hub 8 in UpLink Port or Normal Port, it doesn't work. Network/Hub is working as everybody can connect to Servers/Printers.

Is this type of connection possible or an incompatibility problem?. In general a Router is used but some people consulted confirmed this is possible as ISP uses DHCP and ARP/Address Resolution Protocol tied with MAC/Media Access Control Address.

If it won't work with just one computer turned on, you have a problem with the uplink port or its cabling. The cable modem must be connected to the uplink port unless you use a reversed patch cord.

For both to work, your ISP must provide two IP addresses or you must use a router.

Kip, it turns we have two problems: first one, may be UpLink Port because we tested with several working straight through cables and when a Normal Hub Port is used with a Cross Over cable one of the Computers work. Second one is even more elusive because only one Computer works and we do not have a pattern here, it looks like using DHCP still needs DNS Addresses in TCP/IP Control Panel and that can not be done in Basic Mode and you are forced to use Advanced/Administration Mode besides making a change in any parameter to force a saving of a new configuration.

Connection of second Computer is not possible, even when ISP mentions Modem allows access of multiple users if defined with them, which is for two users in our case. If you quit first connection and somehow you manage to connect the second Computer, then first one can not connect. When quitting second one and try to connect again the first one, you have some problems until you restart, turn off/on Modem or do something like that.

ISP uses a scheme where they use Modem's MAC Address to control users in their Network and assign Local Type Addresses like 10.10.x.x to the Computer making the connection. They commented having no problem with some Wintel Networks, but I suspect Routing configuration used to define and control access and business may be the problem because under this configuration we are a sub-sub net and never granted a real Internet Address, Static or Dynamic. In theory ISP would be using DHCP.