DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
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Figure 4 - 9 In Band Manage Settings
Select the priority and click Apply.
SRED
Simple random early detection (sRED) is a simplified RED mechanism based on ASIC capability. Random Earl y
Detection (RED) is a congestion avoidance mechanism at the gateway in packet switched n etworks. RED gateways
keep the average queue size low while allowing occasional bursts of pac kets in the queue. The switch provides
support for sRED through active queue management by probabilistic dropping of incoming colored packets.
Active queue management is a class of algorithms that attempt to proactivel y drop or mark frames befor e congestion
becomes excessive. The goal is to detect the onset of persistent congestion and tak e proactive action so that TCP
sources contributing to the congestion back off gracefully, insuring good networ k utilization while minimizing frame
loss.
This proactive approach starts discarding specific colored packets before the packet buf f er becomes full. If this queue
depth is less than the threshold, there is minimal (or no) cong estion and the packet is enqueued. If congestion is
detected the packet is dropped or queued based on the DSCP.

SRED Settings

To view this window, click QoS > SRED > SRED Sett ings as shown below:
Figure 4 - 10 SRED Settings window
The following parameters may be set:
Parameter Description