Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010, Configuration Manual

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A stacked VLAN (S-VLAN) provides a two-level VLAN tag structure, which extends
the VLAN ID space to more than 16 million VLANs.
Creating an S-VLAN requires the use of a second encapsulation tag. The router
performs decapsulation twice, once to get the S-VLAN tag and once to get the VLAN
tag. This
double tagging approach enables more than 16 million address possibilities,
which more than satisfies the scaling requirement for Ethernet B-RAS applications.
VLAN and S-VLAN subinterfaces can coexist over the same VLAN major interface.
You configure S-VLANs in the same way that you configure VLANs, with the addition
of certain commands.
NOTE: See JUNOSe Release Notes , Appendix A , System Maximums for S-VLAN
limitations.
Like VLANs, all S-VLAN subinterfaces use the MAC address of the Ethernet interface
over which they are configured. For more information about assigning unique MAC
address to the S-VLAN subinterface when assigning VLAN or S-VLAN IDs, see “VLAN
Overview” on page 169.
VLAN and S-VLAN Platform Considerations
You can configure VLAN and S-VLAN subinterfaces on the following E Series
Broadband Services Routers:
■
E120 router
■
E320 router
■
ERX1440 router
■
ERX1410 router
■
ERX710 router
■
ERX705 router
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ERX310 router
Module Requirements
For information about the modules supported on E Series routers:
■
See the ERX Module Guide for modules supported on ERX7xx models, ERX14xx
models, and the ERX310 router.
■
See the E120 and E320 Module Guide for modules supported on the E120 and
E320 routers.
Interface Specifiers
The configuration task examples in this chapter use the format for ERX7xx models,
ERX14xx models, and the ERX310 router to specify a VLAN or S-VLAN subinterface.
VLAN and S-VLAN Platform Considerations
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Chapter 5: Configuring VLAN and S-VLAN Subinterfaces