Comment 4 for bug 611336

The Gnome NetStatus Applet uses these icons to show if data is being sent or received. The Gnome Network Monitor does not use this idle icon to show the wired connection status (it's distinct from 'networkwired.png'), which I think is your concern.

If the idle icon is the same as the transmit-receive icon, the applet is not providing the desired information (is the network idling or is it active?). Other standard themes distinguish these two icons, usually by indicating activity in either direction (transmit or receive) with a distinct 'on' symbol, such as light on a monitor, c.f. the human icon theme, where the network-wired icon is used rather than network-idle:

http://bazaar.launchpad.net/~ubuntu-branches/ubuntu/maverick/human-icon-theme/maverick/download/head%3A/networkwired.png-20100331141318-n6ylp4tkw1yysi69-18/network-wired.png

http://bazaar.launchpad.net/~ubuntu-branches/ubuntu/maverick/human-icon-theme/maverick/download/head%3A/networktransmitrecei-20091205110421-6zee3ly4x0w9rb46-357/network-transmit-receive.png

The Humanity theme's icons for 'transmit only' or 'receive only' instead designate the absence of signal in the opposing direction by cutting the alpha of that part of the symbol, and this should hold true for the idle icon (as in my patch). The concern that this suggests a disabled state is mitigated by it's use in the netstatus applet, and typically frequent switches between the idle and active states.

The alternative for this theme is to have fully opaque components represent inactivity, and use a colour (or some other symbol change) to denote activity, but this is not particularly desirable.