Using Service Availability

This article describes the Service Availability (SA) function and how to set it up in your Metro Ethernet Network. The SA function is used to determine the number of unavailable seconds and other counters for a specific service. You can use the SA function to verify if the service sold to a client meets a specific SLA, with the help of your EMS.

You can define Service Availability instances with one or more SA metrics (criteria) that will be used to determine unavailable seconds. Each criterion has its own threshold. The basic criteria (SA metric) for determining unavailable seconds, as defined in the MEF 10.2 Technical Specification, is the CFM frame loss. The unit supports the following SA metrics:

• CFM frame loss
• DMM one- way delay
• DMM one-way delay variation
• DMM two-way delay
• DMM two-way delay variation
• PAA packet loss
• PAA one-way delay
• PAA one-way delay variation
• PAA two-way delay
• PAA two-way delay variation
• SLM near-end frame loss
• SLM far-end frame loss

Follow these steps to set up Service Availability:

• Add a Service Availability instance: "Setting Up Service Availability".
• Add one or more SA metrics: "Setting Up an SA Metric".
• Put a Service Availability instance into service: "Putting an SA Instance into Service".

Setting Up Service Availability

To configure service availability

1. Access the page SOAM ▶SA ▶Configuration.
   A summary of all SA instances is displayed.

2. Click Add to create a new SA instance or click the SA instance name to edit an existing SA instance.

3. Complete the required fields, then click Apply.

For more information on specific parameters, refer to the following table.

SA Configuration (SOAM ▶SA ▶Configuration)'

Client Port Cut-Off Feature

Client Port Cut-off allows the client to configure a network performance threshold below which the client port is automatically disabled in order to advertise the link failure to a peer network.

A user-configurable timer is available to define the time to wait before restoring the link after the network performance has returned to normal. Default value is 120. Range is 0–300 seconds in increments of 1 second.

A user-configurable timer is available to define the time to wait before disabling the client port after the network performance has fallen below the configured threshold. Default value is 0. Range is 0–120 seconds in increments of 1 second.

Deleting an SA Instance

To delete a Service Availability instance

1. Access the page SOAM ▶SA ▶Configuration.
   A summary of all SA instances is displayed.

2. Click the SA instance Name to delete.

3. Click Delete.

Setting Up an SA Metric

An SA metric defines the criteria used to assess any unavailable seconds. You must add one or more SA metrics for each SA instance. SA metrics are valid only for a specific SA instance. You must first create the CFM instance, DMM instance or PAA probe in its corresponding page before setting up the SA metric.

To set up a Service Availability metric

1. Access the page SOAM ▶SA ▶Configuration.
   A summary of all SA instances is displayed.

2. Click the SA instance Name of the SA instance you want to add or edit the SA metric.

3. At the bottom of the page, click Add to create a new SA metric or click the SA metric Index to edit an existing SA metric.

4. Complete the required fields, then click Apply.

For more information on specific parameters, refer to the following table.

SA Metric (SOAM ▶SA ▶Configuration ▶[SA instance] ▶[SA metric index])

Deleting an SA Metric

To delete a Service Availability metric

1. Access the page SOAM ▶SA ▶Configuration.
   A summary of all SA instances is displayed. For more information on specific parameters, refer to the table above.

2. Click the SA instance Name of the SA instance you want to delete the SA metric.

3. Click the SA metric Index you want to delete.

4. Click Delete.

Putting an SA Instance into Service

Once you have configured the SA Metrics, the SA instance must be put into service.

To put an SA instance into service

1. Access the page SOAM ▶SA ▶Configuration.

2. Click the Name of the SA instance you want to put into service.

3. Select In Service from the State drop-down list.

4. Click Apply.

Viewing SA Counters

Two sets of SA counters are available:

• Periodic: This set of counters provides the results for the current period.
• Monotonic: This set of counters provides the results since the SA instance was created or since the last reset.

To eliminate transient results or to reset the counters, click one of the Clear Statistics buttons.

To view a summary of all Service Availability counters

1. Access the page SOAM ▶SA ▶Counters.

2. Click an SA instance Name to view the detailed counters for this SA instance and its metrics.

For more information on specific parameters, refer to the following two tables.

SA Counters (SOAM ▶SA ▶Counters)

Metric Counters (SOAM ▶SA ▶Counters)