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VLAN Commands
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VLAN Commands
PowerConnect 802.1Q VLANs are an implementation of the Virtual Local
Area Network, specification 802.1Q. Operating at Layer 2 of the OSI model,
the VLAN is a means of parsing a single network into logical user groups or
organizations as if they physically resided on a dedicated LAN segment of
their own. In reality, this virtually defined community may have individual
members scattered across a large, extended LAN. The VLAN identifier is part
of the 802.1Q tag, which is added to an Ethernet frame by an 802.1Q-
compliant switch or router. Devices recognizing 802.1Q-tagged frames
maintain appropriate tables to track VLANs. The first 3 bits of the 802.1Q tag
are used by 802.1p to establish priority for the packet.
PowerConnect supports 802.1Q VLANs. As such, ports may simultaneously
belong to multiple VLANs. VLANs allow a network to be logically segmented
without regard to the physical locations of devices in the network.
PowerConnect switching supports up to 1024 VLANs for forwarding.
VLANs can be allocated by subnet and netmask pairs, thus allowing
overlapping subnets. For example, subnet 10.10.128.0 with Mask
255.255.128.0 and subnet 10.10.0.0 with Mask 255.255.0.0 can have different
VLAN associations.
Double VLAN Mode
An incoming frame is identified as tagged or untagged based on Tag Protocol
Identifier (TPID) value it contains. The 802.1Q standard specifies a TPID
value (0x8100) to recognize an incoming frame as tagged or untagged. Any
valid Ethernet frame with a value 0x8100 in the 12th and 13th bytes is
recognized as tagged frame. 802.1Q switches check the 12th and 13th bytes to
decide the tag status of incoming frame.
The PowerConnect switching component can be configured to enable the
port in double-VLAN (DVLAN) mode. In this mode switch looks for 12th,
13th, 16th, and 17th bytes for the tag status in the incoming frame. The outer
tag (S-TAG) TPID is identified with the 12th and 13th bytes values. The
inner tag (C-TAG) TPID is identified with 16th and 17th bytes values. These
2CSPC4.XCT-SWUM2XX1.book Page 769 Monday, October 3, 2011 11:05 AM
Summary of Contents for PowerConnect 7000 Series
Page 74: ...74 Contents 2CSPC4 XCT SWUM2XX1 book Page 74 Monday October 3 2011 11 05 AM ...
Page 164: ...164 Command Groups 2CSPC4 XCT SWUM2XX1 book Page 164 Monday October 3 2011 11 05 AM ...
Page 266: ...266 AAA Commands 2CSPC4 XCT SWUM2XX1 book Page 266 Monday October 3 2011 11 05 AM ...
Page 316: ...316 Auto VoIP Commands 2CSPC4 XCT SWUM2XX1 book Page 316 Monday October 3 2011 11 05 AM ...
Page 368: ...368 DHCP Snooping Commands 2CSPC4 XCT SWUM2XX1 book Page 368 Monday October 3 2011 11 05 AM ...
Page 454: ...454 Ethernet CFM Commands 2CSPC4 XCT SWUM2XX1 book Page 454 Monday October 3 2011 11 05 AM ...
Page 468: ...468 Green Ethernet Commands 2CSPC4 XCT SWUM2XX1 book Page 468 Monday October 3 2011 11 05 AM ...
Page 558: ...558 IP Source Guard Commands 2CSPC4 XCT SWUM2XX1 book Page 558 Monday October 3 2011 11 05 AM ...
Page 578: ...578 Link Dependency Commands 2CSPC4 XCT SWUM2XX1 book Page 578 Monday October 3 2011 11 05 AM ...
Page 606: ...606 LLDP Commands 2CSPC4 XCT SWUM2XX1 book Page 606 Monday October 3 2011 11 05 AM ...
Page 700: ...700 QoS Commands 2CSPC4 XCT SWUM2XX1 book Page 700 Monday October 3 2011 11 05 AM ...
Page 728: ...728 RADIUS Commands 2CSPC4 XCT SWUM2XX1 book Page 728 Monday October 3 2011 11 05 AM ...
Page 808: ...808 VLAN Commands 2CSPC4 XCT SWUM2XX1 book Page 808 Monday October 3 2011 11 05 AM ...
Page 814: ...814 Voice VLAN Commands 2CSPC4 XCT SWUM2XX1 book Page 814 Monday October 3 2011 11 05 AM ...
Page 848: ...848 802 1x Commands 2CSPC4 XCT SWUM2XX1 book Page 848 Monday October 3 2011 11 05 AM ...
Page 850: ...850 Layer 3 Commands 2CSPC4 XCT SWUM2XX1 book Page 850 Monday October 3 2011 11 05 AM ...
Page 912: ...912 DHCPv6 Commands 2CSPC4 XCT SWUM2XX1 book Page 912 Monday October 3 2011 11 05 AM ...
Page 920: ...920 DVMRP Commands 2CSPC4 XCT SWUM2XX1 book Page 920 Monday October 3 2011 11 05 AM ...
Page 946: ...946 IGMP Proxy Commands 2CSPC4 XCT SWUM2XX1 book Page 946 Monday October 3 2011 11 05 AM ...
Page 1062: ...1062 IPv6 Routing Commands 2CSPC4 XCT SWUM2XX1 book Page 1062 Monday October 3 2011 11 05 AM ...
Page 1174: ...1174 OSPF Commands 2CSPC4 XCT SWUM2XX1 book Page 1174 Monday October 3 2011 11 05 AM ...
Page 1234: ...1234 OSPFv3 Commands 2CSPC4 XCT SWUM2XX1 book Page 1234 Monday October 3 2011 11 05 AM ...
Page 1294: ...1294 Utility Commands 2CSPC4 XCT SWUM2XX1 book Page 1294 Monday October 3 2011 11 05 AM ...
Page 1304: ...1304 Auto Install Commands 2CSPC4 XCT SWUM2XX1 book Page 1304 Monday October 3 2011 11 05 AM ...
Page 1348: ...1348 CLI Macro Commands 2CSPC4 XCT SWUM2XX1 book Page 1348 Monday October 3 2011 11 05 AM ...
Page 1366: ...1366 Clock Commands 2CSPC4 XCT SWUM2XX1 book Page 1366 Monday October 3 2011 11 05 AM ...
Page 1478: ...1478 RMON Commands 2CSPC4 XCT SWUM2XX1 book Page 1478 Monday October 3 2011 11 05 AM ...
Page 1518: ...1518 Sflow Commands 2CSPC4 XCT SWUM2XX1 book Page 1518 Monday October 3 2011 11 05 AM ...
Page 1578: ...1578 Syslog Commands 2CSPC4 XCT SWUM2XX1 book Page 1578 Monday October 3 2011 11 05 AM ...
Page 1646: ...1646 Telnet Server Commands 2CSPC4 XCT SWUM2XX1 book Page 1646 Monday October 3 2011 11 05 AM ...
Page 1686: ...1686 Web Server Commands 2CSPC4 XCT SWUM2XX1 book Page 1686 Monday October 3 2011 11 05 AM ...
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