Specifications

Chapter 1 Introduction Installation and Operation Manual
1-12 Functional Description RICi-4E1/T1, RICi-8E1/T1 Ver. 2.0
VLAN-Unaware Mode
In this mode the bridge forwarding ignores the VLAN ID of VLAN tagged frames.
Each Ethernet packet received from each bridge port (Ethernet or E1s) is
forwarded according to its destination MAC address.
Bridge Features
• Learning and forwarding according to MAC address only
• Learning of up to 2048 MAC addresses
• Configuration of the aging time
• VLAN tagged frames transparency (forwarding according to MAC only)
• MAC table viewing (learned MACs).
Ingress Process
All frames are accepted in this mode: untagged, priority-tagged or VLAN-tagged.
Learning and forwarding is based on the MAC addresses, with no regard to the
VLAN. This mode is sometimes regarded to as transparent mode, due to “tag
transparency”.
Learning Process
The learning process observes the source MAC address (SA) of the received frame
and updates the forwarding database (FDB) with the MAC and the bridge port
that the frame was received from. FDB is also referred to as MAC table.
The learning process inserts a new entry into the MAC table. This entry consists
of the MAC and the bridge port.
• If the MAC already exists for the same bridge port, the aging time will be
updated.
• If the MAC already exists, but for a different bridge port, (dynamic entry) the
new entry will override the existing one.
Aging Process
The aging process checks the forwarding MAC table periodically. Each dynamic
entry aging time period that has exceeded the configured Aging Time Limit is
deleted. The aging time period is the period of time since the last frame for this
entry has 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.