Few questions on full duplex/ half duplex.
Posted on 2004-10-25
Please correct any incorrect assumptions. Thanks
1. Both 10base T and 100BaseT can run in either half duplex or full duplex.
When 10baseT operates in half duplex, it uses how many pairs? 2 pair? What about when it operates in full duplex? Does it use 2 pair still? The speed of 10baseT half duplex is 10mbps. But does this speed increase if 10baseT is run in full duplex?
2. Now 100baseT operates at 100mbps in half duplex. And it uses all 4 physical wires? 100baseT full duplex uses 2 pair? What is the speed of 100baseT full duplex ....200mbps?
3. Switches provide point to point connections for hosts, so they can communicate in full duplex. What happens if your network card is only capable of half duplex. Does the switch then act like a "hub"?
4. Hubs can only run in half duplex because they dont provide point to point connections. They forward all frames they receive to every connected host.
If you have a 6 port 10/100 hub, and all clients have 100mb nics. The 100mb is spread out over all 6 users.
If you have a 6 port 100mb switch, and all clients have 100mb nics. Each user gets 100mb.
5. What is the point of having a 1gig backbone, if all of your desktops only have 100mb nics?