Termination Point Encapsulation

Description

Termination Point Encapsulation (TPE) is a modeling concept defined within the 3GPP Management and Orchestration (MANO) framework, specifically in the context of the Network Resource Model (NRM). A Termination Point (TP) represents an endpoint of a logical or physical link where connectivity is provided, such as a port on a switch, a virtual network interface, or a radio antenna connector. TPE provides a standardized way to encapsulate and describe these termination points, including their attributes, capabilities, and relationships to other managed objects.

Architecturally, TPE is realized as an information object class within the NRM, often inheriting from a base Managed Function or Managed Element class. It contains attributes that define the TP's role (e.g., source or sink), its directionality (input, output, bidirectional), its associated protocol stack, and its binding to physical hardware or virtualized resources. In a virtualized network function (VNF), a TPE might represent a virtual network interface card (vNIC) with specific bandwidth and latency properties. The management system, such as an Element Management System (EMS) or Network Management System (NMS), uses the TPE model to discover, configure, monitor, and troubleshoot connectivity.

How it works involves the integration of TPE definitions into the descriptors used for network service and VNF onboarding, such as the VNF Descriptor (VNFD). During the lifecycle management orchestrated by an NFV Orchestrator (NFVO), the instantiation of a VNF involves creating instances of its modeled termination points and connecting them to other TPs in the network to form service chains. TPE enables a uniform management interface across heterogeneous network equipment, whether physical network functions (PNFs) or VNFs. Its role is critical for automating service deployment and ensuring that connectivity requirements are precisely met in complex, sliced networks.

Purpose & Motivation

TPE was created to address the challenge of managing connectivity endpoints in increasingly software-defined and virtualized networks. Prior approaches often used vendor-specific or equipment-specific models for ports and interfaces, making automated, multi-vendor service provisioning and assurance complex and error-prone. TPE provides a common abstraction layer.

The problem it solves is the lack of a standardized information model for termination points within the 3GPP management architecture. With the advent of Network Functions Virtualization (NFV) and Software-Defined Networking (SDN), networks became composed of dynamically instantiated functions with virtual connections. TPE, as part of the standardized NRM, allows management systems to understand and manipulate these connections uniformly, regardless of whether the underlying function is physical or virtual. This was motivated by the need for agile service delivery and efficient resource utilization in 5G and beyond, where network slicing requires precise control over connectivity endpoints for each slice instance.

Key Features

• Standardized abstraction for logical and physical connection endpoints
• Defined as an information object class within the 3GPP Network Resource Model (NRM)
• Supports attributes for role, direction, protocol, and resource binding
• Essential for modeling connectivity in VNF and Network Service Descriptors
• Enables automated configuration and lifecycle management of connections
• Facilitates uniform fault and performance monitoring of termination points

Evolution Across Releases

Defining Specifications