Security; Resilient Links - IBM 8271 Nways F12 User Manual

1-8 C 1: I
HAPTER NTRODUCING THE

Security

Resilient Links

S
WITCH
In the Model F12 and F24, Flow Control is implemented in two ways:
IEEE 802.3x standard for ports operating in full duplex.
Intelligent Flow Management (IFM), a method of flow control for
ports operating in half duplex. IFM should only be enabled if the
port is connected to another switch, or an endstation. If the port is
connected to a repeated segment with local traffic, IFM should be
disabled.
For information about enabling flow control on a port, see
"Configuring a Port on the Switch" on page 4-16.
Each port in the stack can use a Security feature that guards against
unauthorized users connecting devices to your network. When Security
is enabled on a port, it enters Single Address Learning Mode. In this
mode, the port learns a single MAC (Ethernet) address; once this is
learned, the port is disabled if a different address is seen on the port.
Until Security is disabled, no other address can be learned.
For more information about enabling Security on a port, see
"Configuring a Port on the Switch" on page 4-16.
The Resilient Link feature of the stack enables you to protect critical
links and prevent network downtime should those links fail. Setting up
resilience ensures that if a main communication link fails, a standby
duplicate link immediately and automatically takes over the task of the
main link. Each main and standby link pair is referred to as a resilient
link pair.
Resilient links are a simple method of creating redundancy that provides
you with an instant reaction to link failure. Resilient Links are quick to
set up, you have full control over their configuration, and the port at
the other end of the resilient link does not have to support a particular
resilience feature.
ATTENTION: Resilient links and Spanning Tree cannot be set up on the
same stack.
For more information about Resilient Links, see "Setting Up Resilient
Links for the Stack" on page 4-31.