What's duplex mismatch

numby SG

i recently do a online speed test and got tis... what does it mean by Alarm: Duplex mismatch condition exists: Host set to Full and Switch set to Half duplex

TCP/Web100 Network Diagnostic Tool v5.3.3e
click START to begin
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
running 10s outbound test (client to server) . . . . . 226.54Kb/s
running 10s inbound test (server to client) . . . . . . 1.16Mb/s
Your PC is connected to a Cable/DSL modem
Alarm: Duplex mismatch condition exists: Host set to Full and Switch set to Half duplex
Information: The receive buffer should be 39.47 Kbytes to maximize throughput

click START to re-test

StarPuppy SG

Duplex mismatch:

a duplex mismatch is a condition where two connected devices operate in different duplex modes, that is, one operates in half duplex while the other one operated in full duplex.
The effect of a duplex mismatch is a network that works but is often much slower than its nominal speed.
Duplex mismatch may derive from manually setting two connected network interfaces at different duplex mode, but also derives from connecting a device that performs autonegotiation to one that is manually set to a full duplex mode.

numby SG

i am connected to a router, anything to do with it?

ndmmxiaomayi SG

Use either a router or switch only, unless you are maintaining a network, which requires the use of both routers and switches.

By right, this shouldn't happen, since switches and routers allow you to work in full duplex mode, meaning you can send and receive files simultaneously. It could be the way you configure your router or switch, especially if you let them auto configure.