VLANs are most commonly segment- or port- based, requiring network administrators to define manually VLAN associations that form broadcast domains based on organizational functions rather than accidents of physical location or IP address assignment.

• vlan最常见的是基于网段或端口，需要网络管理员人工定义vlan的关联性，这构成了基于组织功能的广播域，而不是基于物理位置或ip地址分配的偶然性。