Switch Port; Uplink And Subtending Modes; Flow Control - ZyXEL Communications MSC1024G Series User Manual

Chapter 15 Switch Screens
Figure 340 MSTP Configuration Example: Port
8 For switch B, configure the same general MSTP settings and VLAN-to-MST mappings
as switch A for the subtending ports.
9 Set the subtending port priorities on switch B to allow MSTP to forward traffic to the
corresponding link.
In MSTID1, set the subtending port 1 priority to 0 and subtending port 2 priority to 240.
In MSTID2, set the subtending port 1 priority to 240 and subtending port 2 priority to 0.
Devices belonging to the same MST region must have the same settings in the
Config Name and Revision Level fields and VLAN-MST instance
mapping(s).

15.11 Switch Port

This section describes the switch port features and parameters.

15.11.1 Uplink and Subtending Modes

The Gigabit Ethernet SFP slots and ports can function in either subtending or uplink mode.
Connect a port in uplink mode to an backbone Ethernet switch or router. The management
switch card allows traffic between the ports in uplink mode and the DSL ports on the line
cards.
Use the subtending mode to daisy-chain other Ethernet switches. With subtending mode, the
management switch card allows traffic between the ports in subtending mode and the ports in
uplink mode. The management switch card does not allow traffic between the ports in
subtending mode and the DSL ports on the line cards.

15.11.2 Flow Control

A concentration of traffic on a port decreases port bandwidth and overflows buffer memory
causing packet discards and frame losses. Flow control is used to regulate transmission of
signals to match the bandwidth of the receiving port.
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MSC1000G/1024G/1224G Series User's Guide