Packet scheduler miniport

What does “- Packet Scheduler miniport” represents in WinXP. It is there
at multiple places in the registry. XP adds this string at the end of the
miniport driver DriverDesc in some cases. My INF has proper name and thats
exactly that appears in the device manager and under enum->pci->…
registry keys. However there is this key that shows it by adding this
string at the end, which is :

HKLM\system\current control set\enum\root\MS_PSCHEDMP\FriendlyName.

What is the meaning of appending this string?