Huawei Technologies Huawei Technologies KPN Verizon Inc. Energy Sciences Network Neighbor Discovery (ND) is a critical part of IPv6. ND uses multicast extensively and trusts all hosts. In some scenarios, such as wireless networks, multicast can be inefficient. In other scenarios, such as public access networks, hosts may not be trustworthy. Consequently, ND can have issues in some scenarios. The issues and mitigation solutions are documented in more than 20 RFCs, making it challenging to track all these issues and solutions. Therefore, an overview document is helpful. This document first summarizes the published ND issues and the solutions. This provides a one-stop reference. This document then analyzes these mitigation solutions to reveal that isolating hosts into different subnets or links can help prevent ND issues. Three isolation methods and their applicability are described. A simple guideline is provided for selecting a suitable isolation method to prevent potential ND issues.