What is the difference between half duplex and full duplex networking?
Half Duplex Ethernet Bridge
Ethernet IEEE 802.3 standard defines half duplex as a digital signal on a wire pair flowing in both tracks on the wire. Half duplex networking uses the same wire, or connection to send data both ways. It is like having a one way street, in which you send data from the transmitter node, to receiver node and then wait for a response. Although this happens in milli-seconds, there is latency on the network connection. For half duplex point to point wireless networking, this latency is compounded by over the air interference, reflection, signal loss, channel interference, and the size of the data packets being transmitted. Basic 802.11N Wireless Bridge Kits, and even the newer 802.11AC point to point wireless bridge packages are half duplex. Although most of the time, and for most applications, you will not notice the latency over the connection, for some instances you will want the least amount of dropped packets. When using VoIP, sending large files, playing xbox, or transmitting video files across the link, full duplex is recommended.
Full Duplex Ethernet Bridge
On the other hand, full duplex Ethernet employs two pairs of wires. Full duplex always provides faster networking, as with the point to point connection between the transmitter of source node and the receiver of destination node. If we compare full duplex vs half duplex, full duplex point to point is much faster, and will provide faster throughput for voice, data and video transmission. Collisions do not occur in the full duplex Ethernet mode because the source antenna is sending data on one frequency, and receiving data on another frequency, or channel. Full duplex Ethernet mode is 100% efficient for both tracks (receivers & transmitters). Full duplex offers the connection speed 10 to 1000Mbps, and newer point to point wireless bridges can transmit up to 6Gbps! Full duplex Ethernet bridge links are similar to having a two land highway where traffic can be sent and received at the same time, without any collisions, or slow down in traffic. As a full duplex Ethernet port is turned on it connects to the remote node then connects to the other nodes of the Ethernet link. The auto detect mechanism determines the transmission exchange rate, means either it can run at 10Mpbs or 100Mbps or 1000Mbps.
Full duplex Ethernet bridge kits are recommended for the following conditions:
- Large amounts of VoIP between two locations
- Point to point wireless of more than 2 miles distance
- Transfer of IP network cameras, or remote monitoring
- Higher security options available
- Higher throughput requirements of up to 6Gbps
- Better obstruction penetration abilities for long range wireless
GNS Wireless stocks the following Full Duplex, high throughput, point to point links:
- Ubiquiti airFiber 1000Mbps Full Duplex Backhaul
- Cambium Networks PTP 650 Series Wireless Backhaul
- Bridgewave 60Ghz and 80GHz Wireless Backhaul
- Pre-Packaged Full Duplex Commercial Point to Point Wireless Bridge Kits up to 220Mbps