HP Networking TopTool Products manual Class of Service, Port Settings, 13-10

Managing Switches

Configuring Switch Features

Table 13-2. Port Settings

Setting	Description
Port	The port number. The port may be appended with one of the following:
	• Trkx—The port trunk to which this port belongs
	• Mesh—The port has been assigned to a switch mesh domain
	• MP—The port is a Monitor Port
Port Type	The MAC layer type, for example, 100VG or FDDI.
Enabled	Whether the port is enabled or disabled.
Config Mode	The speed and duplexing for the port. Auto mode will negotiate with the
	device on that port to determine the mode.
	Click on Modify Selected Ports to change the mode.
Flow Control	Indicates the current state of flow control for this port. When disabled,
(not available	the port does not generate flow control packets and drops any flow
on	control packets it receives.
the HP J3298	•	10/100TX, 10FL, 100FX:
A or HP		– On—Flow control is enabled.
J3299A)		– Off—Flow control is disabled (default).
	•	Gigabit:
		– On (TX, RX)—Flow control is enabled on transmit and receive.
		– On (RX)—Flow control on receive only.
		– Off (default)—Flow control is disabled.
Bcast Limit	The Broadcast Limit, expressed as a percentage of broadcast packets
(not available	relative to the theoretical limit. Any broadcast or multicast traffic
on	exceeding this limit will be dropped. A value of zero indicates that no limit
the HP J3298	is to be applied.Values range from 0-99.
A or HP
J3299A)

Class of Service

There will always be points in the network where multiple traffic streams merge or where network links will change speed and capacity. It is important to move traffic on the basis of relative importance. Without CoS prioritization, less important traffic can consume network bandwidth and slow down or halt the delivery of more important traffic. For example, without CoS, most traffic received by a switch is forwarded with the same priority it had when entering the switch. In many cases, such traffic is “normal” priority and competes for bandwidth with all other normal-priority traffic, regardless of its relative importance to your organization’s mission. CoS keeps the most important network traffic moving at an acceptable speed, regardless of current band- width usage. This means you can manage available bandwidth so that the switch transmits the most important traffic first.

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