In computer networking, the term link aggregation applies to various methods of combining (aggregating) multiple network connections in parallel in order to increase throughput beyond what a single connection could sustain, and to provide redundancy in case one of the links should fail. A LAG (Link Aggregation Group) combines a number of physical ports together to make a single high-bandwidth data path, so as to implement the traffic load sharing among the member ports in the group and to enhance the connection reliability.
Other umbrella terms used to describe the method include port trunking,[1]link bundling,[2]Ethernet/network/NIC bonding,[1] or NIC teaming. These umbrella terms encompass not only vendor-independent standards such as Link Aggregation Control Protocol (LACP) for Ethernet defined in IEEE 802.1AX and IEEE 802.1aq or the previous IEEE 802.3ad, but also various proprietary solutions.
Figure 1 Diagram for Ethernet link aggregation
Figure 2 Network diagram for Layer 2 static aggregation
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