In public wireless
LAN (PWLAN) setups, a high number of ISG sessions might be unauthenticated
sessions from wireless devices that do not use the PWLAN service. These
sessions are referred to in this document as walk-by sessions, and users that
use these sessions are referred to as walk-by users.
if not dealt with in an optimized way, may consume a large portion of the
hardware resources. This resource utilization may lead to an increase in the
number of ISG routers required for a given PWLAN deployment. The concept of
light-weight sessions is introduced to provide an optimization for walk-by
The features for
walk-by users are configured on a default session acting as a template. Walk-by
users are then assigned light-weight sessions that inherit features from a
default session. The features are configured only once on the default session,
thereby optimizing the resource usage.
A lite session is a
light-weight unauthenticated ISG session that inherits default session
services. Lite sessions are created on ISG to support walk-by users and
optimize resource usage. A timer may be specified to limit the duration for
which the lite session can utilize the public wireless LAN (PWLAN) services
while remaining unauthenticated.
On the ASR 1000
Series router, the Layer 4 Redirect (L4R) feature supports a maximum of 16
translation entries per walk-by session. For more information on the limit for
the total number of translations on the system, see
Layer 4 Redirect Scaling.
platform-independent restrictions pertaining to the walk-by sessions and
information on how to configure the Walk-By User Support for PWLAN in ISG
feature, refer to the following URL: