Cisco Cisco ASR 5500
Mobile Video Gateway Overview
▀ Features and Functionality
▄ MVG Administration Guide, StarOS Release 17
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For histogram logging, the TCP link monitoring feature keeps a counter for every bit rate or RTT range. Whenever a
new sample of TCP traffic is generated, a corresponding counter is updated. The collection server retrieves these values
based on the configured sampling rate. There are four histogram plots: video bit rate, video RTT, non-video bit rate, and
non-video RTT. For each of these plots, a total of 36 counters are used for logging.
new sample of TCP traffic is generated, a corresponding counter is updated. The collection server retrieves these values
based on the configured sampling rate. There are four histogram plots: video bit rate, video RTT, non-video bit rate, and
non-video RTT. For each of these plots, a total of 36 counters are used for logging.
For time-series logging, the sampling rate is the same as that of the remote update time for the collection server.
Typically, this can be configured in 30-minute intervals. As with histogram logging, there are four time-series counters:
video bit rate, video RTT, non-video bit rate, and non-video RTT.
Typically, this can be configured in 30-minute intervals. As with histogram logging, there are four time-series counters:
video bit rate, video RTT, non-video bit rate, and non-video RTT.
Congestion Management
Congestion can happen more frequently in a cellular network than in a wired network due to various factors such as
airlink interface, high RTT for wireless connections. In this release, MVG supports TCP link state monitoring and
estimation of congestion level at subscriber side airlink interface. The congestion level thus estimated can be sent to
CAE during the start of a video flow. Based on this information, CAE can decide to stream video appropriately
optimized for the subscriber side network. If the first flow from the subscriber itself is video, that flow cannot have
congestion level value. The Congestion Management feature makes use of the existing Link Monitoring feature. So to
enable congestion management, link monitoring has to be enabled.
airlink interface, high RTT for wireless connections. In this release, MVG supports TCP link state monitoring and
estimation of congestion level at subscriber side airlink interface. The congestion level thus estimated can be sent to
CAE during the start of a video flow. Based on this information, CAE can decide to stream video appropriately
optimized for the subscriber side network. If the first flow from the subscriber itself is video, that flow cannot have
congestion level value. The Congestion Management feature makes use of the existing Link Monitoring feature. So to
enable congestion management, link monitoring has to be enabled.
Congestion detection is based on all types of data traffic - video and non-video, and works only for TCP traffic. CLI
support is provided to configure the parameters to interpret the congestion indications per TCP flow and correlate them
for a subscriber to allow experimentation. Congestion sampling time and reporting frequency can also be configured.
Congestion monitoring is done in the downlink direction only.
support is provided to configure the parameters to interpret the congestion indications per TCP flow and correlate them
for a subscriber to allow experimentation. Congestion sampling time and reporting frequency can also be configured.
Congestion monitoring is done in the downlink direction only.
CLI support is provided to enable or disable the Congestion Management feature at either APN or subscriber.
URL Stripping
The URL Stripping feature allows the ASR5000 to strip a specific URL argument from the URL, based on ECS
configuration. A CLI command in the ACS Charging Action Configuration mode is defined to specify the URL token to
be stripped.
configuration. A CLI command in the ACS Charging Action Configuration mode is defined to specify the URL token to
be stripped.
For the following URL, http://www.videoserver.com?Name1=val1&Name2=val2&Name3=val3 if the CLI command is
applied, this will strip parameter
applied, this will strip parameter
name2
and its optional value
val2
from the above URL to give the following new
URL: http://www.videoserver.com?Name1=val1&Name3=val3. If the token name does not match, then charging action
will not be applied.
will not be applied.
In case of CAE readdressing, to avoid recursive redirection of requests to the CAE, it is mandatory that the rule used to
match stripurl charging action must have higher priority than the rule used to match CAE readdressing charging action.
This will make sure that if the URL contains a configured token, the request will not be readdressed again and the token
will be stripped by URL stripping charging action before request is sent to the origin server.
match stripurl charging action must have higher priority than the rule used to match CAE readdressing charging action.
This will make sure that if the URL contains a configured token, the request will not be readdressed again and the token
will be stripped by URL stripping charging action before request is sent to the origin server.
Limitations of URL stripping:
URL stripping has a limitation in case of partial packets. In cases where the HTTP Request header is split into
multiple packets, the token will not be stripped from URL while forwarding the request to the origin server.
This is because ECS does not buffer the HTTP packets for rule matching and added buffering will have
performance impact.
This is because ECS does not buffer the HTTP packets for rule matching and added buffering will have
performance impact.
URL stripping must have higher priority than Request-Readdressing in the rulebase. Otherwise even if the URL
contains the token, Request-Readdressing will happen before token is stripped.
URL Stripping cannot be used with Response-Readdressing feature. Once the URL is stripped and sent to the
new destination, the response may contain video. Hence if Response-Readdressing is enabled, it will be
readdressed back to the CAE server causing loop condition.
readdressed back to the CAE server causing loop condition.