PDN Gateway Overview
Features and Functionality - Optional Enhanced Feature Software ▀
Cisco ASR 5x00 Packet Data Network Gateway Administration Guide ▄
85
Subscriber data statistics that are required to ensure that accounting information is maintained
A best-effort attempt to recover various timer values such as call duration, absolute time, and others
Session recovery is also useful for in-service software patch upgrade activities. If session recovery is enabled during the
software patch upgrade, it helps to preserve existing sessions on the active PSC/PSC2 during the upgrade process.
Important:
For more information on session recovery support, refer to the
Session Recovery
chapter in the
System Administration Guide
.
Smartphone Tethering Detection Support
Use of Smartphone Tethering Detection requires that a valid license key be installed. Contact your local Sales or
Support representative for information on how to obtain a license.
On the P-GW, using the inline heuristic detection mechanism, it is now possible to detect and differentiate between the
traffic from the mobile device and a tethered device connected to the mobile device.
Traffic Policing
Use of Per-Subscriber Traffic Policing requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
Traffic policing allows you to manage bandwidth usage on the network and limit bandwidth allowances to subscribers.
Traffic policing enables the configuring and enforcing of bandwidth limitations on individual subscribers and/or APNs
of a particular traffic class in 3GPP/3GPP2 service.
Bandwidth enforcement is configured and enforced independently on the downlink and the uplink directions.
A Token Bucket Algorithm (a modified trTCM) [RFC2698] is used to implement the Traffic-Policing feature. The
algorithm used measures the following criteria when determining how to mark a packet:
Committed Data Rate (CDR)
: The guaranteed rate (in bits per second) at which packets can be
transmitted/received for the subscriber during the sampling interval.
Peak Data Rate (PDR)
: The maximum rate (in bits per second) that subscriber packets can be
transmitted/received for the subscriber during the sampling interval.
Burst-size
: The maximum number of bytes that can be transmitted/received for the subscriber during the
sampling interval for both committed (CBS) and peak (PBS) rate conditions. This represents the maximum
number of tokens that can be placed in the subscriber’s “bucket”. Note that the committed burst size (CBS)
equals the peak burst size (PBS) for each subscriber.
The system can be configured to take any of the following actions on packets that are determined to be in excess or in
violation:
Drop
: The offending packet is discarded.
Transmit
: The offending packet is passed.
Lower the IP Precedence
: The packet’s ToS bit is set to “0”, thus downgrading it to Best Effort, prior to
passing the packet. Note that if the packet’s ToS bit was already set to “0”, this action is equivalent to
“Transmit”.