HP 5300XL, 5304XL, 5348XL Figure 11-1.Example of Routing Between VLANs via an External Router

Port-Based Virtual LANs (VLANs) and GVRP

Port-Based Virtual LANs (Static VLANs)

eliminated and bandwidth is saved by not allowing packets to flood out all ports. An external router is required to enable separate VLANs on a switch to communicate with each other.

For example, referring to figure 11-1,if ports A1 through A4 belong to VLAN_1 and ports A5 through A8 belong to VLAN_2, traffic from end-node stations on ports A2 through A4 is restricted to only VLAN_1, while traffic from ports A5 through A7 is restricted to only VLAN_2. For nodes on VLAN_1 to communi­ cate with VLAN_2, their traffic must go through an external router via ports A1 and A8.

Switch with Two

VLANs Configured

		VLAN_1	Port A2
			Port A3
	Port A1		Port A4
External
Router			Port A5
	Port A8
			Port A6
			Port A7
		VLAN_2

Figure 11-1. Example of Routing Between VLANs via an External Router

Overlapping (Tagged) VLANs. A port on the Series 5300XL switches can be a member of more than one VLAN if the device to which they are connected complies with the 802.1Q VLAN standard. For example, a port connected to a central server using a network interface card (NIC) that complies with the 802.1Q standard can be a member of multiple VLANs, allowing members of multiple VLANs to use the server. Although these VLANs cannot communicate with each other through the server, they can all access the server over the same connection from the switch. Where VLANs overlap in this way, VLAN “tags” are used to distinguish between traffic from different VLANs.

11-4