English Compex 24-Port + 1 Expansion Slot Switch
SAS2224B
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4.4. Quality of Service
Quality of Service (QoS) refers to the capability of a network to provide a better service
to selected ports in the switch. A port with priority set High will have its transmitted
packets serviced first at the receiving port.
Compex SAS2224B can recognize QoS priority information from the incoming packets
and distribute packets in different queues for different service priority. It identifies the
packets’ priority based on:
TOS/Diff Serv. Priority:
This stands for Type of Services/Differentiated Services Priority. When TCP/IP's
TOS/DiffServ (DS) based priority is applied, Compex SAS2224B can recognize TCP/IP
Differentiated Services Codepoint (DSCP) priority information from the DS-field
defined on RFC2474. The DS field byte for IPv4 is the Type-of-Service (TOS) octet,
and for IPv6, it is the Traffic-Class octet. The recommended DiffServ Codepoints is
defined in RFC2597 to classify the traffic into different service classes.
802.1p Priority:
802.1p is an IEEE standard for providing quality of service (QoS) in Ethernet networks.
It uses tagged packets and allows switches to transmit packets based on the tagged
priority value.