Access RAD ASMi-54, Инструкция по установке и эксплуатации

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Chapter 1 Introduction Installation and Operation Manual
1-10 Functional Description ASMi-54 Ver. 1.0
entry entered the bridge. The periodic check of the MAC table (aging time
intervals), results in an actual aging time that can reach up to twice the value that
was configured by the user.
Forwarding Process
The forwarding process is performed based on the frame MAC Destination
Address (MDA). The frame is forwarded to the bridge/port specified in the MAC
table for this MAC.
Frames are forwarded, dropped, or flooded at this stage:
•
Forwarded: A frame will be forwarded according to its DA, to the bridge port
where its DA was learned.
•
Dropped: If the port for that DA entry in the MAC table is the port on which
the frame was received, the frame will be dropped.
•
Flooded:
If there is no information regarding the DA in the MAC table, the frame is
flooded to all ports
Frames with multicast or broadcast addresses are flooded to all ports.
Transmission Process
In this bridge mode (VLAN-Unaware), the frames are transmitted unchanged, that
is no tags are added or removed.
VLAN Stacking
VLAN Stacking mode for a bridge port refers to the addition of a tag to an
incoming frame either at ingress or egress (regardless of whether it already has
an existing VLAN tag), and removal of a tag at ingress or egress when the frame
leaves from this port.
This setting is independent of the bridge activity.
VLAN Stripping
VLAN Stripping mode for a bridge port refers to the removal of a tag at ingress or
egress when the frame leaves from this port.
This setting is independent of the bridge activity.
Quality of Service
ASMi-54 supports QoS mapping to priority queues (4 PQ, strict priority, per bridge
port) at the DSL egress direction, according to one of the following:
•
VLAN priority (802.1p)
•
DSCP (bits 0-5 in IP TOS byte)
•
Port based