Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - LINK LAYER CONFIGURATION GUIDE 2010-10-13 Configuration Manual page 555

Copyright © 2010, Juniper Networks, Inc.
The lockout time range comprises two values: a minimum lockout time and a maximum
lockout time. The initial lockout time begins with the minimum lockout time. From this
point, the lockout time increases exponentially for every successive lockout event within
the greater of 15 minutes or the maximum configured lockout time. The lockout time
never exceeds the maximum value of the time range.
For example, using the default lockout time range of 1–300 seconds, the increasing
lockout time sequence is: 1 second, 2 seconds, 4 seconds, 8 seconds, 16 seconds, 32
seconds, 64 seconds, 128 seconds, 256 seconds, and finally, 300 seconds (5 minutes).
Encapsulation Type Lockout Based on DSL Forum VSAs for IWF PPPoE Sessions
JunosE Software supports the dynamic encapsulation type lockout functionality for
PPPoE sessions that contain the IWF-Session DSL Forum VSA (26-254) in the PPPoE
active discovery request (PADR) packets. For interworking function (IWF) sessions that
involve a set of functions to be processed to interconnect two networks of different
technologies (such as PPPoE over ATM to PPPoE), the encapsulation type lockout for
the PPPoE clients associated with the dynamic PPPoE subinterface column on the PPPoE
major interface is determined using a combination of the Agent-Circuit-Id (26-1) and
Agent-Remote-Id (26-2) DSL Forum VSAs, in addition to the MAC address.
The DSL Forum VSAs used in the encapsulation type lockout process for IWF PPPoE
sessions comprise Agent-Circuit-Id (26-1) and Agent-Remote-Id (26-2). The
Agent-Circuit-Id VSA is the identifier for the subscriber agent circuit that corresponds to
the DSLAM interface from which subscriber requests are initiated. The Agent-Remote-Id
VSA is the unique identifier for the subscriber associated with the DSLAM interface from
which requests are initiated. For PPPoE sessions with the IWF-Session VSA, if you
configured the pppoe auto-configure lockout-time command in Interface Configuration
mode or Subinterface Configuration mode, the MAC address, Agent-Circuit-Id, and
Agent-Remote-Id values are used together to identify a subscriber to implement PPPoE
lockout.
If subscriber PPP sessions are transported on PPPoE, the PPPoE intermediate agent on
the DSLAM adds the Agent-Circuit-Id and Agent-Remote-Id VSAs to the PPPoE PADI
and PADR packets. The PPPoE implementation technique captures both the
Agent-Circuit-Id and the Agent-Remote-Id sub-options from every PADR packet for every
PPPoE session. Dynamic encapsulation type lockout is enabled by default for all IWF
PPPoE sessions.
Guidelines for Configuring Encapsulation Type Lockout for PPPoE sessions
The following rules apply when you configure the lockout time for dynamic encapsulation
type lockout:
The lockout time value is defined as
(minimum lockout time) * (2 ^ n-1)
where n represents the number of consecutive lockout events.
The router increments the value of n when the time between lockout events is either
within 15 minutes or the maximum lockout time, whichever is greater.
Chapter 17: Configuring Dynamic Interfaces
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