ZyXEL Communications ES3500 Series 36.3 Activating DiffServ, PIR, CIR, YES, YES, Red, CIR, PIR, YES, YES, YES, YES, Loss, Loss, Loss, Loss, Loss, Loss, Loss, Loss, Yellow, Exceed NO, Exceed NO

Chapter 36 Differentiated Services

36.2.1 TRTCM-Color-blind Mode

All packets are evaluated against the PIR. If a packet exceeds the PIR it is marked red. Otherwise it is evaluated against the CIR. If it exceeds the CIR then it is marked yellow. Finally, if it is below the CIR then it is marked green.

Figure 159 TRTCM-Color-blind Mode

Exceed NO		Exceed NO
				Low Packet
PIR?		CIR?		Loss
	YES		YES
High Packet		Medium Packet
Loss		Loss

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 160 TRTCM-Color-aware Mode

	NO	Exceed NO			NO	Exceed NO
								Low Packet
Red?				Yellow?		CIR?		Loss
		PIR?
	YES		YES		YES		YES
High Packet		High Packet		Medium Packet		Medium Packet
Loss		Loss		Loss		Loss

36.3 Activating DiffServ

Activate DiffServ to apply marking rules or IEEE 802.1p priority mapping on the selected port(s).

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	ES3500 Series User’s Guide