Technology Description; Stack Physical Connection - Huawei S Series White Paper

S Series Switches
iStack Technology White Paper

2.1 Stack Physical Connection

As shown in Figure 2-1, switches in a stack can be connected in a chain or ring topology.
Table 2-1 compares the two topologies.
A stack usually uses a ring topology. In the ring topology, member switches are connected to
each other through stack cables. iStack blocks a stack link to prevent looping of data packets
on stack links.
Figure 2-1 Stack connection topologies
Master
Table 2-1 Comparisons between two stack topologies
Advantages
Issue 01 (2013-05-25)
2

Technology Description

iStack
Standby Slave
Chain topology
Ring Topology
Provides high reliability.
When a stack link in a ring
topology fails, the ring
topology becomes a chain
topology.
Data can be forwarded
along the shortest path,
improving bandwidth usage
of stack links.
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2 Technology Description
Master
iStack
Standby
Ring topology
Chain Topology
Applies to long-distance stacking because
the first and last devices do not need to be
physically connected.
Slave
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