Avaya 8800 Planning And Engineering page 107

such a configuration issue, whereas SLPP reacts and disables the malfunctioning links,
minimizing the impact on the network.
In addition to using SLPP for loop prevention, you can use the extended CP-Limit softdown
feature to protect the SF/CPU against Denial of Service (DOS) attacks where required. The
extended CP-Limit harddown option should only be used as a loop prevention mechanism in
Software Release 3.7.x.
SLPP and SMLT examples
The following configurations show how to configure SLPP so that it detects VLAN-based
network loops for untagged and tagged IEEE 802.1Q VLAN link configurations.
The following figure shows the network configuration. A and B exchange untagged packets
over the SMLT.
Figure 34: Untagged SMLT links
For the network shown in
consists of the following:
• SLPP-Tx is enabled on SMLT VLAN-10.
• On switches A and B, SLPP-Rx is enabled on untagged access SMLT links.
• On switch A, the SLPP-Rx threshold is set to 5.
• In case of a network failure, to avoid edge isolation, the SLPP rx-threshold is set to 50 on
SMLT switch B.
This configuration detects loops and avoids edge isolation. For tagged data, consider the
following configuration:
Planning and Engineering — Network Design
Figure 34: Untagged SMLT links
SLPP, Loop Detect, and Extended CP-Limit
on page 107, the configuration
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