L-PDF Overview

Local policy decision functionality for application-related services adds support for a new process that regulates collection of statistics related to applications and application groups and tracking of information about dynamic subscribers and static interfaces. This functionality is collectively named the local policy decision function (L-PDF). L-PDF is supported on:

• MX Series routers equipped with Multiservices DPCs.

• M120 or M320 routers equipped with Multiservices 400 PICs.

• Aggregated Multiservices (AMS) PICs.

Multiple ms- interfaces can be bundled together in an AMS PIC interface, which causes the traffic destined for this AMS group to be distributed over the member services PICs of the group. Junos OS Trio chipsets enable the calculation of a symmetric hash for the forward and reverse flows, and support a microcode map in the forwarding plane. This capability enables load-balancing of traffic across various services PICs in an AMS group. Starting with Junos OS Release 12.1, ams- interfaces enable an N:1 redundancy mechanism to cluster together N number of ms- interfaces in an AMS group that supports load sharing.

Starting with Junos OS Release 11.3, local L-PDF that resides on the services PIC is supported on T320, T640, and T1600 routers. The application identification (APPID) service defines the applications and how they are grouped. The application-aware access list (AACL) service defines the applications and application groups for which statistics are collected for a specific user or interface. The L-PDF configuration defines the way in which the statistics are output.

To configure properties for statistics output, include the policy-decision-statistics-profile statement at the [edit accounting-options] hierarchy level. A new traceoptions configuration is available at the [edit system services local-policy-decision-function] hierarchy level. To configure a dynamic profile to attach a specified service set to an interface, include the service statement at the [edit dynamic-profiles profile-name interfaces interface-name unit logical-unit-number family inet] hierarchy level. To attach a service set to a static interface, include the service-set service-set-name statement at the [edit interfaces interface-name unit logical-unit-number family inet service (input | output)] hierarchy level. For more information on service sets, see Understanding Service Sets.

The following related operational commands are supported:

• show services local-policy-decision-function flows

• show/clear services local-policy-decision-function statistics

• show/clear services application-aware-access-list statistics

For more information on the CLI configuration, see the Best-Effort Application Identification of DPI-Serviced Flows. For more information on the operational commands, see the CLI Explorer.