Huawei Technologies Huawei Technologies China Mobile China Telecom Futurewei Technologies Verizon Inc. China Mobile Juniper Networks Juniper Networks The IETF Network Slice service aims to meet the connectivity demands of a network slice customer with specific Service Level Objectives (SLOs) and Service Level Expectations (SLEs) over a common underlay network. A Network Resource Partition (NRP) is a set of network resources that are allocated from the underlay network to carry a specific set of network traffic and meet the required SLOs and SLEs. One or multiple IETF Network Slice services can be mapped to one NRP. As the demand for IETF Network Slice services increases, scalability would become an important factor for the large scale deployment of IETF Network Slices. Although the scalability of IETF Network Slices can be improved by mapping a group of IETF Network Slices to one NRP, there are concerns about the scalability of NRPs. This document describes the scalability considerations about NRPs in the network control plane and data plane, and some optimization mechanisms are proposed.