The Source netgraph now includes "lerp" indicator which shows the actual interpolation amount (usually 100 msec unless the server or user is forcing non-default settings). The indicator will turn yellow if the server's framerate (actual framerate on the remote machine) drops below this interval. This can be used to figure out why all of the objects in the world are no longer moving smoothly. In addition, the indicator will turn orange if the user or server has tuned the ConVars such that the interpolation amount is less than 2 / updaterate. This indicates that if there is any packet loss (or possibly choke if the choke is occurring for long periods of time due to large packets being sent over a low bandwidth rate setting) that the player will likely see sluggishness in the game.

Here's the Valve's Wiki page about the Orange/TF2 netgraph: http://developer.valvesoftware.com/wiki ... work_Graph.. At the very bottom:


In summary:
white - OK
yellow - not OK
orange - bad
black - you're AFRICAN AMERICAN