Figure 12: Load Balancing In Aggregated Links - GE T1000 Technical Manual

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link. Thus, if there is different bandwidth traffic between end nodes, there will be a
non-perfect load balancing. In the end, the apparent link speed will increase, and
there will be a redundant path for the traffic of the end nodes. Figure below shows an
example of such behaviour, and the method for load balancing used is source MAC
address.

Figure 12: Load balancing in aggregated links

Even though the total speed of the ports is 300 Mbps, there are only 170 Mbps being
used and one of the links is not forwarding any traffic. Even though there is one port
available, if MAC address A or B requires more bandwidth, the extra traffic will be
generated on ports already used
Finally, Aggregation can only be used by ports which have the same speed-
capability, i.e., fast Ethernet ports can be aggregated to create a '200 Mbps link', but
a fast Ethernet and a gigabit Ethernet ports cannot be aggregated to create a '1,100
Mbps link'. When using aggregation, ports have a key which is related to their speed.
This key is observed by the protocol, and only ports with the same key number can
be part of an aggregation group.
Chapter 4 – Functions
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