FireAza wrote:I've been reading up on switches, and I've seen some gigabit switches saying stuff like "2Gbps per port in full duplex mode". What the hell? Is it a 1gbps or a 2gbps switch, which is it?
Speeds are measured in three ways for marketing purposes: link speed (10Mbps, 100Mbps, 1Gbps), max theoretical transfer speed (like the 2Gbps in full duplex, sending and receiving 1Gbps at the same time), and maximum actual speeds (500Mbps actual throughput, for example). All are meant to mislead you to some degree, with the max actual throughput being the smallest lie. Here's why.
When working with network throughput, all traffic measurements are done using IP-based traffic. It makes sense, as it's the most common protocol. However, there are ancillary protocols to IP, the two most common of which are TCP (transmission control protocol) and UDP (user datagram protocol). These have differing levels of overhead, as the computer has to keep track of more information for TCP connections than for UDP connections. Frequently, companies will use uniform-sized packets with UDP to measure throughput. The packets are sometimes jumbo packets, too, which can be up to six times larger than standard packets, reducing overhead. It causes a huge headache for people like me trying to size enterprise-level equipment, and when it causes us
headaches, the average home user is pretty much totally lost.
However, in the absence of all other information, trust the company that provides actual throughput. A crappy network chip can link at gigabit speeds but only move 80Mbps (0.08Gbps) on a good day and still claim to be gigabit. The best computers generally max out at around 600Mbps, mostly because they can't come up with data to feed the stream fast enough for very long, so the chips aren't designed to handle max link speeds.
Still, do some research. Something that moves 150Mbps may work just as well for you as something that can move 400Mbps, and be half the cost.
If I show up at your door, chances are you did something to bring me there.