CHAPTER3
Virtual Switches•Layer2 Features for a SwitchingEnvironment on page 39
•ConfiguringVirtual Switches as SeparateRouting Instances on page 40
Layer2 Features for a Switching Environment
JuniperNetworks MX Series Ethernet Services Routersinclude all standard Ethernet
capabilitiesas well as enhanced mechanisms for serviceproviders to provision and
supportlarge numbers of Ethernet services in addition to all Layer3 services. The MX
Seriesrouters include several featuresto contain and control the Ethernet environment.
Oneof these features is the virtual switch. MX Series routersallow the collapsing of
multiplediverse switch networksto a single platform by running virtual instances of as
manySpanning TreeProtocols (STPs) asneeded to support all broadcast domains. This
isimportant because there are many incompatible versionsof STP, and without a way
torun multiple virtual instances, a separateswitch would be needed to support each
one.With MX Series virtual switch configuration, youcan continue to running existing
STPprotocols with the option to migrateto a common STP protocol if desired.
Virtualswitches also make it easyto separate independent switched Ethernet networks,
eachpossibly carryingseveral VLANs. Because the same VLAN ID can be used in multiple
switchednetworks,virtual switches can keep each VLAN and broadcastdomain logically
separated.
NOTE: Ina router environment, there is alwaysa default routing instance.
Whenyou need only one routing instance on the router,you use the default
routinginstance without qualification. However,if you need more than one
routinginstance, you must configurestatements to create additional routing
instances.In a switching environment, the same is true of virtual switches: if
youneed more than one virtual switch in addition to the “default,”you must
createthem.
Formore information about STPs and virtual switches, see the JunosOS Layer 2
ConfigurationGuide.
Related
Documentation
MXSeries Ethernet Services Routers SolutionsPage•
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