Netgear M4300-24X24F (XSM4348S) - Stackable Managed Switch with 48x10G including 24x10GBASE-T and 24xSFP+ Layer 3 Guia Do Administrador

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DiffServ 
275
 Managed Switches
8. 
Apply policy_vlan to interface 1/0/13.
a. Select QoS > DiffServ > Advanced > Service Interface Configuration
A screen similar to the following displays.
b.  Under Service Interface Configuration, scroll down and select the Interface 1/0/13 
check box. 
c.  In the Policy Name list, select policy_vlan.
d.  Click Apply to save the settings.
WRED Explicit Congestion Notification
Explicit Congestion Notification (ECN) is defined in RFC 3168. Conventional TCP networks 
address congestion by dropping packets using the tail drop algorithm. Random early discard 
(RED, also referred to as random early detection) provides earlier notification than the tail 
drop algorithm and can drop packets that are already queued for transmission. ECN marks 
congested packets that would otherwise be dropped and sends a message to the transmitter 
so that the packets are not retransmitted. That is, the receiver advertises a reduced window 
size to the transmitter but does not request retransmission of the CE-marked packets.
ECN uses the two least significant bits of the Diffserv field (that is, the ToS octet in IPv4 and 
the Traffic Class octet in IPv6) and codes them as follows:
00. Non ECN-Capable Transport, Non-ECT
10. ECN Capable Transport, ECT (0)
01. ECN Capable Transport, ECT (1)
11. Congestion Encountered, CE
TCP also supports ECN through two flags in the TCP header:
ECN-Echo (ECE)
Congestion Window Reduced (CWR)