GE 82-POE Benutzerhandbuch

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Chapter 4: Web-Based Management 
64 
GE-DS-82 and 82-PoE Ethernet Managed Switch User Manual 
VLAN Configuration 
VLAN Overview 
A Virtual Local Area Network (VLAN) is a network topology configured according to a 
logical scheme rather than the physical layout. VLAN can be used to combine any 
collection of LAN segments into an autonomous user group that appears as a single 
LAN. VLAN also logically segment the network into different broadcast domains so 
that packets are forwarded only between ports within the VLAN. Typically, a VLAN 
corresponds to a particular subnet, although not necessarily.  
VLAN can enhance performance by conserving bandwidth, and improve security by 
limiting traffic to specific domains.  
A VLAN is a collection of end nodes grouped by logic instead of physical location. End 
nodes that frequently communicate with each other are assigned to the same VLAN, 
regardless of where they are physically on the network. Logically, a VLAN can be 
equated to a broadcast domain, because broadcast packets are forwarded to only 
members of the VLAN on which the broadcast was initiated. 
NOTE:  
1. No matter what basis is used to uniquely identify end nodes and assign these 
nodes VLAN membership, packets cannot cross VLAN without a network device 
performing a routing function between the VLAN. 
2. The Managed Switch supports IEEE 802.1Q VLAN. The port untagging function can 
be used to remove the 802.1 tag from packet headers to maintain compatibility with 
devices that are tag-unaware. 
The Managed Switch supports IEEE 802.1Q (tagged-based) and Port-Base VLAN 
setting in web management page. In the default configuration, VLAN support is 
"802.1Q".  
•  Port-based VLAN 
Port-based VLAN limit traffic that flows into and out of switch ports. Thus, all devices 
connected to a port are members of the VLAN(s) the port belongs to, whether there is 
a single computer directly connected to a switch, or an entire department. 
On port-based VLAN.NIC do not need to be able to identify 802.1Q tags in packet 
headers. NIC send and receive normal Ethernet packets. If the packet's destination 
lies on the same segment, communications take place using normal Ethernet 
protocols. Even though this is always the case, when the destination for a packet lies