Avaya 8800 Planning And Engineering page 82

Redundant network design
SMLT ID recommendations
SMLT links on both aggregation switches share an SMLT link ID called SmltId. The SmltId
identifies all members of a split multilink trunk group. Therefore, you must terminate both sides
of each SMLT having the same SmltId at the same SMLT client switch. For the exceptions to
this rule, see
mesh configuration
The SMLT IDs can be, but are not required to be, identical to the MLT IDs. SmltId ranges are:
• 1 to 128 for MLT-based SMLTs in R-mode enabled chassis
• 1 to 512 for SLTs
Important:
Avaya recommends to use SLT IDs of 129 to 512 and that you reserve the lower number
IDs of 1 to 128 for SMLT only.
Single Link Trunking (SLT)
Use Single Link Trunking (SLT) to configure a split multilink trunk that uses a single port. A
single-port split multilink trunk behaves like an MLT-based split multilink trunk and can coexist
with split multilink trunks in the same system. However, on each chassis, an SMLT ID can
belong to either an MLT-SMLT or to an SLT. Use SLT to scale the number of split multilink
trunks on a switch to the maximum number of available ports.
On the SMLT aggregation switch pair, split multilink trunks can exist in the following
combinations:
• MLT-based split multilink trunks and MLT-based split multilink trunks
• MLT-based split multilink trunks and SLTs
• SLTs and SLTs
SLT configuration rules include:
• The dual-homed device that connects the aggregation switches must support MLT.
• SLT is supported on Ethernet, and POS ports.
• Assign SMLT IDs of 129 to 512 to SLTs and reserve the lower number IDs of 1 to 128 for
SMLT only.
• SLT ports can be designated access or trunk (that is, IEEE 802.1Q tagged or untagged),
and changing the type does not affect their behavior.
• You cannot change an SLT into an MLT-based SMLT by adding more ports. You must
delete the SLT and then reconfigure the port as SMLT/MLT.
82 Planning and Engineering — Network Design
Figure 23: SMLT square configuration
on page 88.
on page 88 and Figure 24: SMLT full-
November 2010