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n this technology, a device can send and receive at the same time because the send wire is connected directly to the receive wire on both connected devices. This means that we get the full bandwidth of the link (whether 10Mbs, 100Mbs, or 1Gbs) for both transmit and receive, at the same time, for every connected device. If we have a 100Mbs FastEthernet connection using full duplex, it can be said that the total available bandwidth is 200Mbs. This doesn't mean 200Mbs up or 200Mbs down, but is the sum of the full 100Mbs up and 100Mbs down for that link; some sales documentation might gloss over this point in an effort to make the switch look better on paper.

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Posted by crouse

In this technology, a device can send and receive at the same time because the send wire is connected directly to the receive wire on both connected devices. This means that we get the full bandwidth of the link (whether 10Mbs, 100Mbs, or 1Gbs) for both transmit and receive, at the same time, for every connected device. If we have a 100Mbs FastEthernet connection using full duplex, it can be said that the total available bandwidth is 200Mbs. This doesn't mean 200Mbs up or 200Mbs down, but is the sum of the full 100Mbs up and 100Mbs down for that link; some sales documentation might gloss over this point in an effort to make the switch look better on paper.

Full duplex does give us a major boost in efficiency because it allows for a zero-collision environment: if every device connected to a switch can send and receive at the same time, they cannot collide with each other. The only possible conflict is within the switch itself, and this problem is handled by the switch's capability to buffer the frames until the conflict is cleared. Setting up a switch so that every device connected to it is running full duplex is sometimes called microsegmentation because every device has been segmented into its own collision domain, in which there are no collisions. You might see a reference to the collision detection circuit being disabled on a switch as soon as full duplex is selected for a switch port. Note that full-duplex connections can be only point-to-point, meaning one full-duplex device connected to one switch port; half-duplex connections are considered multipoint, which makes sense when you consider that a hub might be connected to a switch port, and there might be several hosts connected to the hub.

Note that not every NIC, whether on a PC or a router, can support full duplex, although it is very rare these days to find a NIC that does not. Most newer NICs have the capability of full duplex, and virtually all switches do as well; furthermore, most NICs and some switches can perform an autosensing function to determine whether the link is full duplex and set themselves accordingly.

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Posted by campbell123

In full-duplex mode, data you transmit does not appear on your screen until it has been received and sent back by the other party.A telephone is a full-duplex device because both parties can talk at once.

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Posted by sagitraz