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VLAN-tagged frames can pass through VLAN-aware or VLAN-unaware network interconnection
devices, but the VLAN tags should be stripped off before passing it on to any end-node host that
does not support VLAN tagging.
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VLAN Classification
When the switch receives a frame, it classifies the frame in one of two ways. If the frame is untagged, the switch assigns the frame
to an associated VLAN (based on the default VLAN ID of the receiving port). But if the frame is tagged, the switch uses the tagged
VLAN ID to identify the port broadcast domain of the frame.
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Port Overlapping
Port overlapping can be used to allow access to commonly shared network resources among different VLAN groups, such as file
servers or printers. Note that if you implement VLANs which do not overlap, but still need to communicate, you can connect them
by enabled routing on this switch.
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Untagged VLANs
Untagged (or static) VLANs are typically used to reduce broadcast traffic and to increase security. A group of network users
assigned to a VLAN form a broadcast domain that is separate from other VLANs configured on the switch. Packets are forwarded
only between ports that are designated for the same VLAN. Untagged VLANs can be used to manually isolate user groups or
subnets.
4.6.3 VLAN Port Configuration
This Page is used for configuring the Managed Switch port VLAN. The VLAN per Port Configuration Page contains fields for
managing ports that are part of a VLAN. The port default VLAN ID (PVID) is configured on the VLAN Port Configuration Page. All
untagged packets arriving to the device are tagged by the ports PVID.
Understand nomenclature of the Switch
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IEEE 802.1Q Tagged and Untagged
Every port on an 802.1Q compliant switch can be configured as tagged or untagged.
Tagged:
Ports with tagging enabled will put the VID number, priority and other VLAN information into the
header of all packets that flow into those ports. If a packet has previously been tagged, the port
will not alter the packet, thus keeping the VLAN information intact. The VLAN information in the
tag can then be used by other 802.1Q compliant devices on the network to make
packet-forwarding decisions.
Untagged:
Ports with untagging enabled will strip the 802.1Q tag from all packets that flow into those
Summary of Contents for NS4750-24S-4T-4X
Page 1: ...NS4750 24S 4T 4X User Manual P N 1702826 REV 00 01 ISS 14JUL14 ...
Page 56: ...56 Figure 4 2 7 Privilege Levels Configuration Page Screenshot ...
Page 110: ...110 Figure 4 4 6 Mirror Configuration Page Screenshot ...
Page 117: ...117 Figure 4 5 4 LACP Port Configuration Page Screenshot ...
Page 174: ...174 Figure 4 7 10 MST1 MSTI Port Configuration Page Screenshot ...
Page 180: ...180 Figure 4 8 2 Multicast Flooding ...
Page 249: ...249 Figure 4 9 18 Voice VLAN Configuration Page Screenshot ...
Page 271: ...271 Counter Counts the number of frames that match this ACE ...
Page 281: ...281 Figure 4 11 4 Network Access Server Configuration Page Screenshot ...
Page 315: ...315 ...
Page 328: ...328 ...
Page 335: ...335 ...
Page 346: ...346 Figure 4 14 1 LLDP Configuration Page Screenshot ...
Page 350: ...350 Figure 4 14 2 LLDP MED Configuration Page Screenshot ...
Page 372: ...372 Figure 4 16 1 Loop Protection Configuration Page Screenshot ...