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BigIron RX Series Configuration Guide
287
53-1002253-01
Chapter
11
VLANs
Overview of Virtual Local Area Networks (VLANs)
Virtual Local Area Networks (VLANs) allow you to segment traffic in a network by placing ports and
interfaces into separate broadcast domains. Each broadcast domain is uniquely identified by VLAN
IDs. These broadcast domains can span multiple devices.
The device supports two types of VLANs:
port-based VLANs
and
protocol-based VLANs
. A
port-based VLAN consists of interfaces that constitutes a Layer 2 broadcast domain. By default, all
interfaces on a BigIron RX are members of the
default
VLAN, which is VLAN 1. Thus by default, all
interfaces on all devices on a network constitute a single Layer 2 broadcast domain. Once you
create a port-based VLAN and assign an interface to that VLAN, that interface is automatically
removed from the default VLAN if the port assigned is untagged. If the port assigned is tagged,
then the port remains as untag on the original VLAN (vlan1) and behaves as dual-mode port.
Tagged, untagged, and dual-mode ports
Interfaces assigned to port-based VLANs can be defined as untagged, tagged, and dual-mode
ports. An untagged port is a member of only one VLAN, while a tagged port can be a member of
more than one VLAN. Thus a tagged port can be a member of more than one broadcast domain.
Dual-mode ports are configured by adding one or more tagged VLANs and one untagged VLAN to a
port.
Tagged ports allow the device to add a four-byte 802.1q tag to the packet. 802.1q tagging is an
IEEE standard that allows a networking device to add information to Layer 2 packets. This
information identifies the VLAN membership of the packet, as well as the VLAN ID of the VLAN from
which the packet is sent. Furthermore, the default tag value of the 802.1q tag is 8100
(hexadecimal). This value comes from the 802.1q specification. You can change this tag value on a
global basis on device if needed to be compatible with other vendors’ equipment.
Figure 21
shows the format of packets with and without the 802.1q tag. The tag format is
vendor-specific. To use the tag for VLANs configured across multiple devices, make sure all the
devices support the same tag format.
Summary of Contents for BigIron RX Series
Page 228: ...152 BigIron RX Series Configuration Guide 53 1002253 01 Enabling WAN PHY mode support 6 ...
Page 312: ...236 BigIron RX Series Configuration Guide 53 1002253 01 Displaying IP information 7 ...
Page 356: ...280 BigIron RX Series Configuration Guide 53 1002253 01 Resetting LLDP statistics 9 ...
Page 402: ...326 BigIron RX Series Configuration Guide 53 1002253 01 Transparent firewall mode 11 ...
Page 432: ...356 BigIron RX Series Configuration Guide 53 1002253 01 SuperSpan 12 ...
Page 500: ...424 BigIron RX Series Configuration Guide 53 1002253 01 MRP CLI example 14 ...
Page 591: ...BigIron RX Series Configuration Guide 515 53 1002253 01 Displaying traffic reduction 19 ...
Page 592: ...516 BigIron RX Series Configuration Guide 53 1002253 01 Displaying traffic reduction 19 ...
Page 598: ...522 BigIron RX Series Configuration Guide 53 1002253 01 Viewing Layer 2 ACLs 20 ...
Page 656: ...580 BigIron RX Series Configuration Guide 53 1002253 01 Trunk formation 22 ...
Page 754: ...678 BigIron RX Series Configuration Guide 53 1002253 01 Displaying RIP filters 24 ...
Page 814: ...738 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPF information 25 ...
Page 980: ...904 BigIron RX Series Configuration Guide 53 1002253 01 Clearing IS IS information 28 ...
Page 1000: ...924 BigIron RX Series Configuration Guide 53 1002253 01 Using secure copy 30 ...
Page 1088: ...1012 BigIron RX Series Configuration Guide 53 1002253 01 IP source guard 35 ...
Page 1108: ...1032 BigIron RX Series Configuration Guide 53 1002253 01 Reading CDP packets 37 ...
Page 1126: ...1050 BigIron RX Series Configuration Guide 53 1002253 01 Clearing sFlow statistics 39 ...
Page 1324: ...1248 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPFv3 information 48 ...
Page 1363: ...BigIron RX Series Configuration Guide 1287 53 1002253 01 Continuous System Monitor 51 ...
Page 1364: ...1288 BigIron RX Series Configuration Guide 53 1002253 01 Continuous System Monitor 51 ...
Page 1404: ...1328 BigIron RX Series Configuration Guide 53 1002253 01 Commands That Require a Reload D ...
Page 1458: ...1382 BigIron RX Series Configuration Guide 53 1002253 01 VSRP E ...