SLM (Service-Level Management)

Many network design projects today require a service-level contract (SLC). This contract may be between two separate enterprises, for example, a customer and a telecommunications provider, or it may be internal to a single enterprise. For example, the IT department may have an SLC to provide services at pre-arranged levels to internal customers, such as other departments that use the IT infrastructure.

The SLC will likely consist of multiple SLAs (service-level agreements). The most common SLA metrics include

• Network availability

• Network delay

• Network delay variation (jitter)

• Packet loss

Regardless of which metrics are used in the SLAs, they should be mapped to application-specific network conditions. The SLC should specify penalties for missed SLAs, as well as specify reporting mechanisms for SLA compliance or non-compliance.

Creation and management of the SLC, as with many other aspects of network design, require skill in both business and technical arenas. While technically adept persons can quickly fabricate SLA criteria such as availability, packet loss, etc., it requires deeper business-impact skills to successfully select SLA criteria and thresholds. Communication between the service provider and the customer regarding actual business needs and agreement upon measurable metrics and agreeable penalty for missed metrics are paramount.

Note

Cisco has a number of tools available that assist in the monitoring of SLAs. For further information, you may want to look into the IPM component of CiscoWorks on Cisco’s website.