LSO Interlude

Dynamic inter-provider service automation.

MEF LSO Interlude APIs

LSO Interlude APIs address the service-orchestration to service-orchestration layer of inter-provider interactions, like performance, state, and dynamic control. The service orchestration functionality is analogous to the OSS functions of a service provider.

Examples of Service Provider interactions handled by LSO Interlude APIs:

  • Request changes to dynamic parameters, as permitted by service policies, on behalf of an enterprise customer.
  • Query operational state of the Service.
  • Request instantiation of connectivity between two service interfaces. 
  • Receive event and performance telemetry.

See MEF’s Technical Standards & Educational Materials for LSO Interlude

MEF Dots Pattern


LSO Interlude Interface Reference Point

LSO Interlude is the Interface Reference Point between the service orchestration layers of disparate service providers who connect to provide access or transit services for a service provider’s end subscriber.

Service Orchestration Functionality Interface Between Providers

Service Orchestration Functionality Interface Between Providers

Learn More about LSO Interlude:

Educational Materials:

MEF 3.0 Workshop – End-to-End Service Automation – LSO Framework and API Standardization — 2019 Nov

Product Portfolio: APIs, LSO Interlude

MEF’s LSO Reference Architecture guides agile development of standardized LSO APIs that enable end-to-end automation of MEF 3.0 services across multiple providers and over multiple network technology domains (e.g., Optical Transport, CE, IP, 5G, etc.).

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Technical Standards & SDKs:

MEF 136 Allegro, Interlude and Legato Service Function Testing Business Requirements & Use Cases — 2023 Apr

Product Portfolio: LSO Allegro, LSO Legato, LSO Interlude

This document defines the Business Requirements and Use Cases to support Service Function Testing (SFT) at the Allegro, Interlude, and Legato Interface Reference Points.

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MEF 133 Allegro, Interlude and Legato Fault Management and Performance Monitoring BR&UC — 2023 Feb

Product Portfolio: LSO Allegro, LSO Legato, LSO Interlude

This document defines the Business Requirements and Use Cases to support Performance Moni-toring at the Allegro, Interlude and Legato Interface Reference Points (IRPs).

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MEF 76 Service Control Business Requirements and Use Cases — 2022 Oct

Product Portfolio: LSO Interlude

Tags: Cloud

This standard defines business requirements and use cases for modifying values of service attributes elastically.

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What Can I Achieve with LSO Interlude APIs?

Starting first with MEF 3.0 Carrier Ethernet services, and later for additional MEF 3.0 services such as IP services, LSO Interlude APIs will drive frictionless inter-provider service operations, resulting in dynamic and automated service delivery and management for off-net subscriber locations.

MEF LSO Interlude API advantages:

  • Enable dynamic service capabilities to off-net subscribers.
  • Support policy-driven control of service attributes.
  • Deliver transparent off-net service performance visibility.
  • Accelerate provisioning cycles.

Be In the Know

Engage in LSO Interlude Knowledge-Sharing

Participating in discussions with subject-matter experts provides the insight you need to understand where the service provider community is headed and to guide the service provider stakeholders in the right direction. As a MEF member, you can discover the latest projects in the MEF LSO Committee Home on the MEF Members’ Wiki.


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