ZyXEL Communications metrogigabit switch Plumbing Product User Manual


 
Chapter 36 Differentiated Services
MGS3700-12C User’s Guide
344
36.2.2 TRTCM-Color-aware Mode
In color-aware mode the evaluation of the packets uses the existing packet loss
priority. TRTCM can increase a packet loss priority of a packet but it cannot
decrease it. Packets that have been previously marked red or yellow can only be
marked with an equal or higher packet loss priority.
Packets marked red (high packet loss priority) continue to be red without
evaluation against the PIR or CIR. Packets marked yellow can only be marked red
or remain yellow so they are only evaluated against the PIR. Only the packets
marked green are first evaluated against the PIR and then if they don’t exceed the
PIR level are they evaluated against the CIR.
Figure 173 TRTCM-Color-aware Mode
36.3 Activating DiffServ
Activate DiffServ to apply marking rules or IEEE 802.1p priority mapping on the
selected port(s).
Exceed
PIR?
High Packet
Loss
Exceed
CIR?
Medium Packet
Loss
NO
YES
NO
YES
Low Packet
Loss
High Packet
Loss
NO
YES
Red?
Yellow?
Medium Packet
Loss
NO
YES