DSCP (Differentiated Services Code Point) marks packets at Layer . This -bit IP header field provides possible values.
Common DSCP values:
- EF (): Expedited Forwarding for voice
- AF41 (): High priority video
- AF21 (): Medium priority data
- CS1 (): Scavenger class for bulk
- Default (): Best effort
AF classes: First digit (-) is priority. Second digit (-) is drop probability. AF41 has higher priority than AF21. AF43 drops before AF41.
DSCP marks persist across Layer boundaries and work end-to-end.