QoS Policies
74 Quality of Service Guide
Customer Service Level Agreement (SLA)
The router implementation of hierarchical QoS allows a common set of virtual schedulers to
govern bandwidth over a set of customer services that is considered to be from the same site.
Different service types purchased from a single customer can be aggregately accounted and
billed based on a single Service Level Agreement.
By configuring multi-service sites within a customer context, the customer site can be used
as an anchor point to create an ingress and egress virtual scheduler hierarchy.
Once a site is created, it must be assigned to the chassis slot or a port (except in the 7450 ESS-
1 model; the slot is automatically set to 1). This allows the system to allocate the resources
necessary to create the virtual schedulers defined in the ingress and egress scheduler policies.
This also acts as verification that each SAP assigned to the site exists within the context of
the customer ID and that the SAP was created on the correct slot, port, or channel. The
specified slot or port must already be preprovisioned (configured) on the system.
When scheduler policies are defined for ingress and egress, the scheduler names contained in
each policy are created according to the parameters defined in the policy. Multi-service
customer sites are configured only to create a virtual scheduler hierarchy and make it
available to queues on multiple SAPs.
Scheduler Policies Applied to Multi-Service Sites
Only an existing scheduler policy and scheduler policy names can be applied to create the
ingress or egress schedulers used by SAP queues associated with a customer’s multi-service
site. The schedulers defined in the scheduler policy can only be created after the customer site
has been appropriately assigned to a chassis port, channel, or slot. Once a multi-service
customer site is created, SAPs owned by the customer must be explicitly included in the site.
The SAP must be owned by the customer the site was created within and the site assignment
parameter must include the physical locale of the SAP.
Shared Queues
Shared-queue QoS policies can be implemented to reduce ingress queue consumption on an
MDA. It is especially useful when VPLS, IES, and VPRN services are scaled on one MDA.
Instead of allocating multiple hardware queues for each unicast or multipoint queue defined
in a SAP ingress QoS policy, SAPs with the shared-queuing feature enabled only allocate one
hardware queue for each SAP ingress QoS policy unicast or multipoint queue.
To Next Page
Loading...
