IFS NS3502-8P-2S User Manual
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Common network applications that use UDP include the Domain Name System (DNS), streaming
media applications such as IPTV, Voice over IP (VoIP), and Trivial File Transfer Protocol (TFTP).
UPnP
UPnP is an acronym for
U
niversal
P
lug and
P
lay. The goals of UPnP are to allow devices to
connect seamlessly and to simplify the implementation of networks in the home (data sharing,
communications, and entertainment) and in corporate environments for simplified installation
of computer components
User Priority
User Priority is a 3-bit field storing the priority level for the 802.1Q frame.
V
VLAN
Virtual LAN. A method to restrict communication between switch ports. VLANs can be used for
the following applications:
VLAN unaware switching:
This is the default configuration. All ports are VLAN unaware with
Port VLAN ID 1 and members of VLAN 1. This means that MAC addresses are learned in VLAN 1,
and the switch does not remove or insert VLAN tags.
VLAN aware switching:
This is based on the IEEE 802.1Q standard. All ports are VLAN aware.
Ports connected to VLAN aware switches are members of multiple VLANs and transmit tagged
frames. Other ports are members of one VLAN, set up with this Port VLAN ID, and transmit
untagged frames.
Provider switching:
This is also known as Q-in-Q switching. Ports connected to subscribers are
VLAN unaware, members of one VLAN, and set up with this unique Port VLAN ID. Ports
connected to the service provider are VLAN aware, members of multiple VLANs, and set up to
tag all frames. Untagged frames received on a subscriber port are forwarded to the provider
port with a single VLAN tag. Tagged frames received on a subscriber port are forwarded to the
provider port with a double VLAN tag.
VLAN ID
VLAN ID is a 12-bit field specifying the VLAN to which the frame belongs.
Voice VLAN
Voice VLAN is VLAN configured specially for voice traffic. By adding the ports with voice devices
attached to voice VLAN, we can perform QoS-related configuration for voice data, ensuring the
transmission priority of voice traffic and voice quality.
W