In April, at the MPLS SD & AI Net World 2023 event in Paris, Nokia successfully passed the EANTC multivendor MPLS/SDN interoperability tests for IP network configuration management and performance monitoring with our Network Services Platform (NSP).

NSP is a comprehensive, programmable platform that makes it simpler to build multivendor networks that combine IP, MPLS, optical and microwave technologies across multiple domains. It includes a complete suite of functions that help communications service providers (CSPs) control, optimize and automate their network operations. NSP makes this possible by taking a model-driven management approach, using data models created with YANG and programmatic interfaces based on protocols such as NETCONF, gRPC/gNMI and model-driven CLI.

During the live interoperability test at this event, we demonstrated how NSP automates the set-up of IETF network slices using SR-MPLS transport in a multivendor network. The network was made up of routers from five different suppliers: the Nokia 7750 SR-1, the Huawei NetEngine 8000 M4, the Ciena 5166, the Juniper MX204 and Ericsson. However, the Ericsson router was not configured by the NSP and was used as pass-by for the services/slices.

This marks an important milestone for Nokia. NSP, functioning as a network slice controller, was the sole NETCONF controller and orchestrator that effectively demonstrated interoperability with routers from various suppliers.

During the test, NSP created a network slice as a layer 3 VPN service with SegmentRouting as the transport. The YANG model provided in the IETF draft “draft-ietf-teas-ietf-network-slice-nbi-yang-04” was used for the northbound interface, and both vendor-specific and OpenConfig models were used for the southbound interface. The test successfully demonstrated all the configuration functions defined by the IETF network slice draft using a subset of attributes. The configuration functions tested were:

1. Creating the slice.
2. Reading the configuration and verifying the state. 
3. Updating the slice. 
4. Deleting the slice.

Finally, the connectivity between all the sites was validated using Internet Control Message Protocol (ICMP) and the Border Gateway Protocol (BGP) status was checked as well.

NSP performed three other tests during this event: 

• L2/L3 service provisioning
• System inventory

Full details on the tests can be found in this EANTC white paper.

We have been participating in EANTC test events with the Nokia NSP on a yearly basis and have successfully completed the interop testing requirements every time. This year, we have proven our leadership in the new campaign for testing multivendor capabilities. You can learn more about our participation in the previous EANTC test events in this blog.

Network services evolution

Network slicing is a network virtualization feature over a common physical network that enables concurrent delivery of end-to-end services that have different and conflicting resource requirements, constraints and deterministic SLAs on throughput, latency and availability. However, network slicing can increase the management challenges. By using automated slicing, CSPs can address these challenges while offsetting any associated cost increases. 

The network slice controller defined by IETF is a key building block that coordinates the creation, monitoring and optimization of transport network slices in multi-domain, multi-technology and multi-vendor environments. It helps CSPs maximize their operational flexibility and efficiency for zero-touch service delivery. It also allows them to leverage existing network investments and consistently enforce SLAs across all the transport slices’ implementations (which is also known as slice realization) in the network.

Transport network slicing is agnostic to various network technologies, including IP, MPLS, and Optical, and there are many applications for it such as 5G services, network wholesale services, and network infrastructure sharing among operators.

Network slice control – abstraction and automation

To automate the lifecycle of transport network slices in a heterogeneous environment, it is essential to have a clear definition of the roles and responsibilities between the orchestrator and the controller and to isolate the orchestration layer from the networking details. 

As defined by the IETF standards, this requires a strict separation between a slice service definition and a slice realization:

• The slice service definition identifies the things that need to be connected, the way they are connected, and the Service Level Objectives and Expectations (SLO-SLEs) that apply.
• Slice realization is the allocation of network resources in such a way that meets the SLO-SLEs.

NSP as network slice controller (NSC)

NSP’s slice controller function provides the key ingredients of transport slice control as defined in the IETF standards and enables the creation of multiple virtual networks on a single physical network infrastructure. This allows CSPs to get the most from their resources when offering customized services to their customers, each with specific requirements for performance, security and other network attributes.

In the role of an NSC, Nokia NSP provides the following capabilities:

• Automated, intent-based life-cycle management
• Path control for label-switched path (LSP) path selection in order to meet the SLO-SLEs, with telemetry-based closed-loop optimization
• Assurance, which involves verifying that the SLOs are being met (OAM tests and performance monitoring) and assisting in trouble shooting (e.g. alarm correlation, event timeline)

Other NSC-specific functionalities that NSP provides are:

• Front-end logic for administering the allocation of slices to LSPs, including the creation of new LSPs when necessary
• A mapping function to translate abstract slice parameters to customer-specific implementation choices (type of intent, SR versus RSVP-TE, TWAMP versus EthCFM, etc.)

NSP benefits and characteristics

The Nokia NSP provides CSPs with a variety of key benefits. It can be integrated seamlessly within a heterogeneous environment, as all the required functions are consolidated in a single product and platform with a common look and feel and easy navigation across all sub-functions. As a full-featured Path Computation Element (PCE), NSP also provides industry-leading and highly scalable real-time path control, which helps the operators maintain the required performance for each slice.

NSP is fully programmable, able to quickly adapt to specific operator needs and provides a mapping function for translating abstract intents into specific implementations to simplify network operations. It includes customizable intents, workflows, device adaptors, KPIs and correlation rules, and a library of pre-defined artifacts. NSP demonstrated this programmatic solution during the EANTC testing event: the platform was configured to translate slice requests in accordance with the given network design in less than a week.