Netgear M4100-26G Software Administration Manual - Page 44

ProSafe M4100 and M7100 Managed Switches Private VLANs The Private VLANs feature separates a regular VLAN domain into two or more subdomains. Each subdomain is defined (represented) by a primary VLAN and a secondary VLAN. The primary VLAN ID is the same for all subdomains that belong to a private VLAN. The secondary VLAN ID differentiates subdomains from each other and provides Layer 2 isolation between ports of the same private VLAN. There are three types of VLAN within a private VLAN: • Primary VLAN - it forwards the traffic from the promiscuous ports to isolated ports, community ports, and other promiscuous ports in the same private VLAN. Only one primary VLAN can be configured per private VLAN. All ports within a private VLAN share the same primary VLAN. • Community VLAN - is a secondary VLAN. It forwards traffic between ports which belong to the same community and to the promiscuous ports. There can be multiple community VLANs per private VLAN. • Isolated VLAN - is a secondary VLAN. It carries traffic from isolated ports to promiscuous ports. Only one isolated VLAN can be configured per private VLAN. There are three types of port designation within a private VLAN: • Promiscuous port - belongs to a primary VLAN and can communicate with all interfaces in the private VLAN, including other promiscuous ports, community ports, and isolated ports. • Community ports - These ports can communicate with other community ports and promiscuous ports. • Isolated ports - These can ONLY communicate with promiscuous ports. The Private VLANs can be extended across multiple switches through inter-switch/stack links that transport primary, community, and isolated VLANs between devices. See figure 1. Figure 4. Private VLANs 44 | Chapter 2. VLANs