GS1920 Series User’s Guide
137
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H A P T E R
1 7
Link Aggregation
17.1
Overview
This chapter shows you how to logically aggregate physical links to form one logical, higher-
bandwidth link.
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. However, the more ports you
aggregate then the fewer available ports you have. A trunk group is one logical link containing
multiple ports.
The beginning port of each trunk group must be physically connected to form a trunk group.
17.1.1
What You Can Do
•
Use the Link Aggregation Status screen (Section 17.2 on page 138) to view ports you have
configured to be in the trunk group, ports that are currently transmitting data as one logical link
in the trunk group and so on.
•
Use the Link Aggregation Setting screen (Section 17.3 on page 139) to configure to enable
static link aggregation.
•
Use the Link Aggregation Control Protocol screen (Section 17.4 on page 141) to enable Link
Aggregation Control Protocol (LACP).
17.1.2
What You Need to Know
The Switch supports both static and dynamic link aggregation.
Note:
In a properly planned network, it is recommended to implement static link
aggregation only. This ensures increased network stability and control over the
trunk groups on your Switch.
See Section 17.5.1 on page 142 for a static port trunking example.
Dynamic Link Aggregation
The Switch adheres to the IEEE 802.3ad standard for static and dynamic (LACP) port trunking.
The IEEE 802.3ad standard describes the Link Aggregation Control Protocol (LACP) for dynamically
creating and managing 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. LACP also allows port redundancy, that
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