Corinex Global GameNet manual Trigger

Adapter Configuration

Several options are available in this form. The first, and easiest to understand and use, is the Default Priority value. Output traffic generated by adapters with higher default priority will have preference in the network. The rest of the parameters let

you configure two Class of Service criteria (Criterion 1 and Criterion 2 check- boxes).

If you select None, 8021p or TOS, custom parameters are hidden, leaving a pre- defined setting in place.

If you select Custom on the other hand, custom parameters are shown as below and can then be configured.

When several traffic flows are sharing the same network, it is sometimes necessary to establish several levels of priority in order to guarantee that bandwidth-sensitive applications like video and telephony function smoothly under network congestion. The traffic classifier is a packet inspector that is able to recognize several patterns in an Ethernet frame, and assign a different priority to each of them. To ensure that the classification is done correctly, there is a trigger mechanism prior to the actual classification. The trigger mechanism is also based on pattern recognition of a given location in each Ethernet packet. The following picture depicts the packet classification mechanism:

Offset								25
Offset
								Ethernet Packet
Bitmask			Bitmask
Pattern			Pattern 1					Prio 1
		=			=
			Pattern 2					Prio 2
						=
			Pattern 3					Prio 3
	Trigger						=
								Prio 8
			Pattern 8				=
				Other				Default Priority

There is one offset, and one bitmask and pattern for the trigger condition. The trig- ger condition is used to make sure that the Ethernet frame contains, for example, an IP frame. To check this condition, the offset must be set to 16 and the bitmask to 0xFFFF. If the resulting pattern is 0x0800, then the Ethernet frame contains an IP packet and the classification can be made to a known field.

There is another offset and bitmask for the classification condition. The resulting value is compared with a set of patterns. If the value matches a given pattern, the packet will be classified with the specified priority. If the value does not match any

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