D-Link GO-DSL-N150 User Manual page 66

differentiated Internet services by giving network resource and usage control to
the Network operator.
QoS::Applications QoS
Select this option to Activated/Deactivated the different application packets
prioritized on the queues.
QoS::VLAN Group QOS
Select this option to Activated/Deactivated the 4094 VID on the 4 different
queues. VID(VLAN ID) is the identification of the VLAN, which is basically used
by the standard 802.1Q. It has 12 bits and allow the identification of 4096 (2^12)
VLANs. Of the 4096 possible VIDs, a VID of 0 is used to identify priority frames
and value 4095 (FFF) is reserved, so the maximum possible VLAN
configurations are 4,094.
VLAN
Virtual LAN (VLAN) is a group of devices on one or more LANs that are
configured so that they can communicate as if they were attached to the same
wire, when in fact they are located on a number of different LAN segments.
Because VLANs are based on logical instead of physical connections, it is very
flexible for user/host management, bandwidth allocation and resource
optimization.
1. Port-Based VLAN: each physical switch port is configured with an access list
specifying membership in a set of VLANs.
2. ATM VLAN - using LAN Emulation (LANE) protocol to map Ethernet packets
into ATM cells and deliver them to their destination by converting an Ethernet
MAC address into an ATM address.
The key for the IEEE 802.1Q to perform the above functions is in its tags.
802.1Q-compliant switch ports can be configured to transmit tagged or untagged
frames. A tag field containing VLAN (and/or 802.1p priority) information can be
inserted into an Ethernet frame. If a port has an 802.1Q-compliant device
attached (such as another switch), these tagged frames can carry VLAN
membership information between switches, thus letting a VLAN span multiple
switches. However, it is important to ensure ports with non-802.1Q-compliant
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User Manual