分為兩類：
Dynamic LACP: 該功能判斷不止是 device 的會況，多了確認封包的動作，以確保整體網路狀況
Static LACP: 單純只判斷 port up & down 的狀況，當線材或 port 有問題，只要是機器一直是 up 的狀況，他任會一直傳送，導至掉包的情況發生
Static Link Aggregation
With a static link aggregate, all configuration settings will be setup on both participating LAG components.
Comment: VMware ESX 4.0 exclusive supports static link aggregation.
The IEEE standard describes controlling link aggregation in Section 5.3 Link Aggregation Control starting on page 23.
Dynamic Link Aggregation: Link Aggregation Control Protocol (LACP)
Beyond that, Link Aggregation Control Protocol (LACP) allows the exchange of information with regard to the link aggregation between the two members of said aggregation. This information will be packetized in Link Aggregation Control Protocol Data Units (LACDUs).
Each individual port can be configured as an active or passive LACP using the control protocol.
Passive LACP: the port prefers not transmitting LACPDUs. The port will only transmit LACPDUs when its counterpart uses active LACP (preference not to speak unless spoken to).
Active LACP: the port prefers to transmit LACPDUs and thereby to speak the protocol, regardless of whether its counterpart uses passive LACP or not (preference to speak regardless).
In contrast to a static link aggregation, LACP provides the following advantages:
Even if one physical links fails, it will detect if the point-to-point connection is using a media converter, so that the link status at the switching port remains up. Because LACPDUs do not form a component of this connection, the link will be removed from the link aggregate. This ensures that packets will not be lost due to the failed link.
Both of the devices can mutually confirm the LAG configuration. With static link aggregation, errors in the configuration or wiring will often not be detected as quickly.
The IEEE standard describes controlling link aggregation in Section 5.4 Link Aggregation Control (LACP) starting on page 30.
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