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Chapter 10 mac table configuration, 1 introduction to mac table, 1 obtaining mac table – QTECH QSW-8300 Инструкция по настройке User Manual

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Chapter 10 MAC Table Configuration

10.1 Introduction to MAC Table

MAC table is a table identifies the mapping relationship between destination MAC addresses

and switch ports. MAC addresses can be categorized as static MAC addresses and dynamic

MAC addresses. Static MAC addresses are manually configured by the user, have the highest

priority and are permanently effective (will not be overwritten by dynamic MAC addresses);

dynamic MAC addresses are entries learnt by the switch in data frame forwarding, and is

effective for a limited period. When the switch receives a data frame to be forwarded, it stores

the source MAC address of the data frame and creates a mapping to the destination port.

Then the MAC table is queried for the destination MAC address, if hit, the data frame is

forwarded in the associated port, otherwise, the switch forwards the data frame to its

broadcast domain. If a dynamic MAC address is not learnt from the data frames to be

forwarded for a long time, the entry will be deleted from the switch MAC table.

There are two MAC table operations:

Obtain a MAC address.

Forward or filter data frame according to the MAC table.

10.1.1 Obtaining MAC Table

The MAC table can be built up statically and dynamically. Static configuration is to set up a

mapping between the MAC addresses and the ports; dynamic learning is the process in which

the switch learns the mapping between MAC addresses and ports, and updates the MAC table

regularly. In this section, we will focus on the dynamic learning process of MAC table.

MAC Table dynamic learning

PC1

MAC 00-01-11-11-11-11

PC4

MAC 00-01-44-44-44-44

PC3

MAC 00-01-33-33-33-33

PC2

MAC 00-01-22-22-22-22

Port 5

Port 12