Cabletron Systems 9E312 사용자 설명서
Filtering Database
3-19
9E312/9E423 Module Bridging
Changing Port Priority
To change the part of the Port Priority used in priority comparisons:
1.
If necessary, select the desired port by clicking the mouse to highlight the port
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
2.
Highlight the port Priority field, and enter the new priority identifier. Only valid
hexadecimal numbers (0 to FF) are allowed in this field. The default is 80
hexadecimal.
hexadecimal numbers (0 to FF) are allowed in this field. The default is 80
hexadecimal.
3.
Click on
. The new port priority will be saved.
Changing Path Cost
To change the Path Cost:
1.
If necessary, select the desired port by clicking the mouse to highlight the port
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
2.
Highlight the Path Cost field, and type in a new value from 1 to 65535 decimal
(default is 100 decimal).
(default is 100 decimal).
3.
Click on
.
The new path cost will be applied to the port.
Filtering Database
When the 9E312/9E423 switch is using Transparent Bridging, the Filtering
Database, which makes up the IEEE 802.1d Source Address Table, is used to
determine which frames will be forwarded or filtered between the 9E312/9E423
Module’s bridging interfaces.
Database, which makes up the IEEE 802.1d Source Address Table, is used to
determine which frames will be forwarded or filtered between the 9E312/9E423
Module’s bridging interfaces.
During initialization, a bridge copies the contents of its Permanent Database to
the Filtering Database. Next, the bridge learns network addresses by entering the
source address and port association of each received packet into the Filtering
Database. When in the Forwarding state, the bridge examines each received
packet and compares the destination address to the contents of the Filtering
Database. If the destination address is located on the network from which the
packet was received, the bridge filters (does not forward) the packet. If the
the Filtering Database. Next, the bridge learns network addresses by entering the
source address and port association of each received packet into the Filtering
Database. When in the Forwarding state, the bridge examines each received
packet and compares the destination address to the contents of the Filtering
Database. If the destination address is located on the network from which the
packet was received, the bridge filters (does not forward) the packet. If the
NOTE
To ensure proper operation of the Spanning Tree Algorithm, the IEEE 802.1d specification
recommends that you always observe the following relationship between Forwarding
Delay, Max Age, and Hello Time:
recommends that you always observe the following relationship between Forwarding
Delay, Max Age, and Hello Time:
2 x (Forwarding Delay - 1.0) > Max Age > 2 x (Hello Time +1.0)