中文（EIP 弹性公网 IP）
EIP 为云资源提供可独立持有与绑定的公网 IPv4 地址，可在不同实例之间灵活迁移，用于对外提供稳定访问入口。
- 典型场景：对外业务入口、需要固定 IP 的白名单接入、故障切换时快速漂移
- 核心能力：弹性绑定/解绑、与 VPC/ULB/安全策略联动，简化公网访问管理
English (Elastic IP - EIP)
EIP provides a public IPv4 address that can be independently owned and bound to cloud resources. It can be reassigned between instances to offer a stable internet-facing endpoint.
- Use cases: public service entry, IP allowlists, quick failover by re-association
- Key capabilities: elastic bind/unbind, works with VPC/ULB/security policies to simplify public access management
