DES-3226 NWay Standalone Fast Ethernet Switch User’s Guide
Diffserv Settings
Figure 7-9. Port Diffserv Settings window
Differentiated Services brings scalable Quality of Service to the Internet Protocol environment, using a Type of Service (TOS) field in the IP header. The Switch has the capability to change the TOS precedence field (the first 3 bits of the TOS field) based on the packet classification.
This window allows you to set the following features:
•From and To – Enter the port or ports to be set.
•Diffserv [Disabled]– Choose from three options: Disabled, DSCP, and TOS.
•Mode – Under DSCP (Differentiated Service Code Point), there are two choices, Change if 0 or Force Overwrite. If Force Overwrite is selected, the differentiated services field of an incoming Ipv4 packet will be overwritten with the entered value. When Change if 0 is selected, the differentiated services field of an incoming Ipv4 packet will be overwritten with the entered value if the original value of the DSCP filed is zero. There are three choices under TOS (Type of Service): TOS Overwrite 802.1p, 802.1p Overwrite TOS, and Force Overwrite. If Force Overwrite is selected, the IP TOS precedence of incoming Ipv4 packets will be overwritten with the entered
