You can create logical subscriber interfaces using static or dynamic IP demux interfaces. IP demultiplexing (demux) interfaces are logical interfaces that share a common, underlying logical interface. IP demux interfaces can be used to identify specific subscribers or to separate individual circuits.
The subscriber interfaces can provide different levels of services for individual subscribers in an access network. For example, you can apply CoS parameters for each subscriber.
Static demux interfaces can be grouped to create individual subscriber interfaces using interface sets. Interface sets enable you to provide the same level of service for a group of subscribers; for example, all residential subscribers who receive the basic data service.
Figure 9 shows a subscriber interface configured using a set of IP demux interfaces with an underlying VLAN interface.
Figure 9: IP Demux Subscriber Interface
You can configure IP demux interfaces to represent a dynamic subscriber interface in a dynamic profile.
Demux interfaces are dynamically created by a DHCP access method when the underlying interface for the demux interface is configured for the access method. The DHCP access model creates the demux interface with the subscriber's assigned IP address.
To configure the demux interface in the dynamic profile, you specify variables for the unit number, the name of the underlying interface, and the IP address. These variables are replaced with the values that are supplied by DHCP when the subscriber logs in.
When you configure static or dynamic IP demux interfaces for subscriber access, consider the following guidelines:
Note: IP demux interfaces currently support only Gigabit Ethernet, Fast Ethernet, and 10-Gigabit Ethernet underlying interfaces.