User’s Manual of NS3550-24T/4S
113
4.6.4 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
■
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. Other 802.1Q compliant
devices on the network to make packet-forwarding decisions can use the VLAN information in
the tag.
Untagged:
Ports with untagging enabled will strip the 802.1Q tag from all packets that flow into those ports.
If the packet doesn't have an 802.1Q VLAN tag, the port will not alter the packet. Thus, all
packets received by and forwarded by an untagging port will have no 802.1Q VLAN information.
(Remember that the PVID is only used internally within the Switch). Untagging is used to send
packets from an 802.1Q-compliant network device to a non-compliant network device.
Frame Income
Frame Leave
Income Frame is
tagged
Income Frame is
untagged
Leave port is tagged
Frame remains tagged
Tag is inserted
Leave port is untagged
Tag is removed
Frame remain untagged
Table 4-6-1
Ingress/Egress port with VLAN VID Tag/Untag table
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IEEE 802.1Q Tunneling (Q-in-Q)
IEEE 802.1Q Tunneling (QinQ) is designed for service providers carrying traffic for multiple customers across their networks.
QinQ tunneling is used to maintain customer-specific VLAN and Layer 2 protocol configurations even when different customers
use the same internal VLAN IDs. This is accomplished by inserting
Service Provider VLAN (SPVLAN)
tags into the customer’s
frames when they enter the service provider’s network, and then stripping the tags when the frames leave the network.
A service provider’s customers may have specific requirements for their internal VLAN IDs and number of VLANs supported.
VLAN ranges required by different customers in the same service-provider network might easily overlap, and traffic passing
through the infrastructure might be mixed. Assigning a unique range of VLAN IDs to each customer would restrict customer
configurations, require intensive processing of VLAN mapping tables, and could easily exceed the maximum VLAN limit of 4096.
Содержание IFS NS3550-24T/4S
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Страница 96: ...96 Figure 4 4 6 Port Mirror Configuration Page Screenshot ...
Страница 127: ...User s Manual of NS3550 24T 4S 127 Figure 4 6 10 Port 1 Port 6 VLAN Configuration ...
Страница 151: ...User s Manual of NS3550 24T 4S 151 Figure 4 8 1 Multicast Service Figure 4 8 2 Multicast Flooding ...
Страница 184: ...184 Figure 4 9 14 Voice VLAN Configuration Page Screenshot ...
Страница 204: ...204 Figure 4 11 4 Network Access Server Configuration Page Screenshot ...
Страница 234: ...234 Figure 4 12 1 Port Limit Control Configuration Overview Page Screenshot ...
Страница 250: ...250 Click to undo any changes made locally and revert to previously saved values ...
Страница 297: ...User s Manual of NS3550 24T 4S 297 ...
Страница 388: ...388 Example Show RADIUS statistics SWITCH security aaa statistics ...
Страница 410: ...410 Parameters vid VLAN ID 1 4095 Default Setting disable ...
Страница 441: ...User s Manual of NS3550 24T 4S 441 Example Enable the mirror mode for port 1 4 SWITCH mirror mode 1 4 enable ...