Shared connection via cable: IP addresses, best cable

Question

Level 1

122 points

Shared connection via cable: IP addresses, best cable

I'm having serious issues regarding connecting Windows machines to my PowerBook, but before I post in that subject, I have a couple of basic questions.

Assume that my Mac is using wireless and has a 192.168.x.x address. I attach another computer to it using an Ethernet cable. Would I expect that other machine to get an IP address of the 192.168.x.x variety, or would it get something else, such 169.254.x.x?

I read on an Apple tech doc that some Macs can detect the cable type and adjust the pinout accordingly, but it never said which models. I have a PowerBook G4 1.7 GHz, the last version shipped before the Intels came out. Anyone know if mine adjusts?

Even if it does adjust, which cable would not require adjustment?

PowerBook G4, 1.7 GHz, Mac OS X (10.4.6), 2 GB

Posted on Jun 4, 2006 2:11 PM

Reply

Answer 1

Jun 4, 2006 2:52 PM in response to Tim Murray2

When you activate Internet Sharing and connect another PC/Mac to your Powerbook, your Powerbook is essentially addressing itself as 192.168.2.1, and the secondary computer will be 192.168.2.2. (Although your Powerbook will still also use the existing addressing that your wireless network assigns it, eg 192.168.1.4 or 10.0.1.3, for example.)

When you set up the secondary computer's networking (if it doesn't configure itself automatically), you'll need to set the Powerbook - 192.168.2.1 - as the DHCP server.

As for your cabling question, you can use either crossover or straight cable, it doesn't matter.

Matt

Reply

Answer 2

Camelot

Level 9

58,311 points

Jun 4, 2006 3:54 PM in response to Tim Murray2

The 169.254.x.x address is what you'll get any time you have the interface set to use DHCP but when there's no DHCP server on the network.

If you just connect the PC to the Mac's ethernet port using direct cable, and neither machine is running a DHCP server then, yes, you'll get a 169.254.x.x address on both the Mac and the Window system.

That's perfectly acceptable and things will work that way. If you don't want to use 169.254.x.x for some reason then either configure one of the machines to run a DHCP server (which can be done by enabling Internet Connection Sharing on the Mac), or assign static IP addresses to each machine's ethernet interface.

As for the cable type question, the basic rule is - gigabit ethernet.
If you Mac has a gigabit ethernet port then it'll auto-detect the cable type. If it only supports 100base-T then you need to provide the correct cable.
In your case your PowerBook has gigabit ethernet and can auto-detect the cable type.

Reply