D-Link xStack DGS-3200-10 - Vlan Segmentation; Vlan and Trunk Groups

xStack
®
DGS-3200 Series Layer 2 Gigabit Ethernet Managed Switch
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An example is presented below:
VLAN Name VID Switch Ports
System (default) 1 5, 6, 7
Engineering 2 9, 10
Sales 5 1, 2, 3, 4
Table 3 - 1. VLAN Example – Assigned Ports
Port-based VLANs
Port-based VLANs limit traffic th at flows into and out of switch ports. Thus, all devices connected to a port are m embers of th e
VLAN(s) the port belongs to, whether there is a single computer directly connected to a switch, or an entire department.
On port-based VL ANs, NICs do not nee d to be able to i dentify 802.1Q tags i n packet heade rs. NICs 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 on another switch port, VLAN considerations come into
play to decide if the packet gets dropped by the Switch or delivered.
VLAN Segmentation
Take for exam ple a pac ket that is transm itted by a m achine on Port 1 t hat is a member of VLAN 2. If t he destination lies o n
another port (found through a normal forwarding table lookup), the Switch then looks to see if the other port (Port 10) is a member
of VLAN 2 (and can therefore receive VLAN 2 packets). If Port 10 is not a member of VLAN 2, then the packet will be dropped
by the Switch and will n ot reach its d estination. If Port 10 is a member of VLAN 2, the packet will g o through. This selective
forwarding feature based on VLAN criteria is h ow VLANs segment networks. The key point being that Port 1 will only transmit
on VLAN 2.
VLAN and Trunk Groups
The members of a trunk grou p have the same V LAN setting. Any VLAN setting on the m embers of a trunk group will apply to
the other member ports.
NOTE: In order to use VLAN segmentation in conjunction with port trunk groups, first set the
port trunk group(s), and then configure the VLAN settings. To change the port trunk grouping
with VLANs already in place it is unnecessary to reconfigure the VLAN settings after changing
the port trunk group settings. VLAN settings will automatically change in conjunction with the
change of the port trunk group settings.