Question about multiple LAN ports

  • Thread starter Thread starter Steve
  • Start date Start date
By using one Lan port to the internet and the other to another computer both
computers can access the internet without the use of a router.
You can connect 2 computers together as a "network" without a router.
peterk
 
"Steve" said:
Can anyone tell me what the purpose of having two lan ports on a mobo are?

Thanks,
Steve
Click to expand...

To share an Internet connection (like ADSL or Cable Modem) with
two computers, you would connect like this. A software, such as
Internet Connection Sharing (ICS - routing software), figures out
which port on the two port equipped motherboard, gets the
packets. I've tried this with a couple of Asus boards, so I
could test Gigabit Ethernet between the two motherboards. The
network speed on either side doesn't have to match.

ADSL <-----> Port1----Mobo_A---Port2 <-----> Mobo_B
Ethernet 230.63.106.21 192.168.1.1 192.168.1.2
Modem

The Ethernet connection between Port2 and Mobo_B, uses a private
Ethernet address. The Ethernet connection from Port1 to the ADSL
modem uses a public address (from your Internet provider).

With Internet Connection Sharing, you have to declare which port
is the private one, and then it gets the 192.168 address. At
least, that is what happened when I tried it out. The only
thing wrong with this network topology (daisy chaining), is
Mobo_A in the figure above, must be running, in order for
Mobo_B to have Internet services.

Paul
 
Thanks, doesn't make much sense since routers are so cheap these days
though. I thought perhaps you could use the 2nd port to double the speed of
a connection to a server or WAN device with dual ports on it.

-Steve


"Steve" said:
Can anyone tell me what the purpose of having two lan ports on a mobo are?

Thanks,
Steve
Click to expand...

To share an Internet connection (like ADSL or Cable Modem) with
two computers, you would connect like this. A software, such as
Internet Connection Sharing (ICS - routing software), figures out
which port on the two port equipped motherboard, gets the
packets. I've tried this with a couple of Asus boards, so I
could test Gigabit Ethernet between the two motherboards. The
network speed on either side doesn't have to match.

ADSL <-----> Port1----Mobo_A---Port2 <-----> Mobo_B
Ethernet 230.63.106.21 192.168.1.1 192.168.1.2
Modem

The Ethernet connection between Port2 and Mobo_B, uses a private
Ethernet address. The Ethernet connection from Port1 to the ADSL
modem uses a public address (from your Internet provider).

With Internet Connection Sharing, you have to declare which port
is the private one, and then it gets the 192.168 address. At
least, that is what happened when I tried it out. The only
thing wrong with this network topology (daisy chaining), is
Mobo_A in the figure above, must be running, in order for
Mobo_B to have Internet services.

Paul
 
Steve a écrit :
Thanks, doesn't make much sense since routers are so cheap these days
though. I thought perhaps you could use the 2nd port to double the speed of
a connection to a server or WAN device with dual ports on it.
Click to expand...

It is possible to make a team with several Intel PRO/100 or PRO/1000.

This team can be used for:
- Fail-over (if one lan fail, the data will use the other card)
- Port agregation (use 2 x 100 Mbps as 1 x 200 Mbps) (you must have
a good switch and often the same configuration at the other end)

3COM and Broadcom cards also have this kind of feature.

There is also a lot of benefit to separate the two Lan, for a better
security, or separating administration and users, or split 50% of the
workstations on one network and the 50% other on the second lan ...

in a Windows MSCS Cluster, the second lan will be used as heart-beat.

By the way, do you really need 8 USB ports on a mobo ??? ;-)

five years ago, the onboard lan was really unusual...

HTH,
Benoît.
 
Back
Top