ZyXEL Communications Dimension GS-3012, User Manual, Page: 113 / 259

GS-3012/GS-3012F User’s Guide
Link Aggregation 14-1
Chapter 14
Link Aggregation
This chapter shows you how to logically aggregate physical links to form one logical, higher-bandwidth
link.
14.1 Introduction to Link Aggregation
Link aggregation (trunking) is the grouping of physical ports into one logical higher-capacity link. You may want
to trunk ports if for example, it is cheaper to use multiple lower-speed links than to under-utilize a high-speed, but
more costly, single-port link. Link aggregation also allows port redundancy, that is, if a port fails, the traffic
automatically goes through another trunk group member port.
However, the more ports you aggregate then the fewer available ports you have. A link aggregation group is one
logical link containing multiple ports.
14.1.1 Dynamic Link Aggregation
The switch adheres to the IEEE 802.3ad standard for static and dynamic (LACP) port trunking.
The switch supports the link aggregation IEEE 802.3ad standard. This standard describes the Link Aggregate
Control Protocol (LACP), which is a protocol that dynamically creates and manages trunk groups.
When you enable LACP link aggregation on a port, the port can automatically negotiate with the ports at the
remote end of a link to establish trunk groups.
Please note that:
You must connect all ports point-to-point to the same Ethernet switch and configure the ports for LACP
trunking.
LACP only works on full-duplex links.
All ports in the same trunk group must have the same media type, speed, duplex mode and flow control
settings.
Configure trunk groups or LACP before you connect the Ethernet switch to avoid causing network topology
loops.
14.1.2 Link Aggregation ID
LACP aggregation ID consists of the following information: