Traffic flow can be managed very well in Windows XP using the
Quality of Service (QoS) Resource Reservation Protocol
(RSVP). However, programs must be designed to take advantage
of this QoS API. The traffic from programs that are not
QoS-aware are sent directly to a different API called
These programs have to fight for bandwidth because unlike the
QoS API, there is no bandwidth reservation. If you use
a lot of QoS-aware programs and would like to change the percent of
the bandwidth that is reserved for the program, read below.
- Make sure your logged on as Administrator. Do not
log on with any account that just has administrator privileges.
- Click on Start -> Logoff ->
- At the logon screen hold Ctrl+Alt+Del.
- In the user field type "Administrator".
- In the password field type the password for the administrator
(if you don't have one leave blank) and press OK.
- Click on the Start button and select run.
- Type gpedit.msc in the text box and click OK.
- Once the program loads, expand the Computer
- Expand the Administrative templates branch.
- Expand the Network branch.
- Highlight the QoS Packet Scheduler in left window.
- In right window double click the limit reservable
- On setting tab check the enabled option.
- Where it says Bandwidth limit %, change it to read what
ever percent you want to reserve for QoS-aware applications.
- Click OK and exit the group policy editor.
- Go to your Network connections (Start -> My
Computer -> My Network Connection -> View
- Right click on your connection, choose properties then under
the General or the Networking tab (where it lists your protocols)
make sure QoS packet scheduler is enabled.
- Now just reboot your computer and you are all done.
When a QoS-aware program is in use it will reserve the allocated
amount of bandwidth and that will take away form other non
QoS-aware programs. However, once the QoS-aware application is
closed or closes the network connection, the bandwidth reservation
This is done by a series of PATH and RESV refresh messages sent
back and fourth over the connection. Once these messages are
no longer detected, the data flow is closed and the reservation of
bandwidth is eliminated.
For more information on QoS Traffic Control: Click
For more information on the control of reservation of