& cplSiteName &

PCRF in the Cloud

Light Reading
Series Column
Light Reading

EXECUTIVE SUMMARY: Cisco's ASR 5000 successfully retrieved policies from the PCRF in the cloud, and throttled customer traffic accordingly.

In 2010 we conducted a comprehensive test of Cisco's mobile solution including mobile core and mobile backhaul (See Testing Cisco's Mobile Core, Data Center & Business Services and Testing Cisco's Next-Gen Mobile Network). At the time, we used a third-party Policy and Charging Rules Function (PCRF) as Cisco had not implemented its own. Now, not only did Cisco have an early version of their PCRF for us to test, but it came with a very timely message -- it was ready to be run in the cloud.

Mobile carriers need PCRF to dictate the rules their subscribers must follow when using the network. These rules could include data allowance, mobility and roaming to name but a few. The Policing and Charging function has been defined both for 3G and Long Term Evolution (LTE) scenarios by the 3rd Generation Partnership Project (3GPP) , and is typically done by a dedicated system with access to subscriber information databases, charging systems and mobile gateways.

In this sense, we think Cisco was wise to port its PCRF to its Unified Computing System, either to be run locally or in a cloud. By doing this, mobile operators could benefit from the flexibility and agility of the cloud, and Cisco has a new use for the UCS systems. With the flexibility of running the PCRF in the cloud comes questions of how many subscribers can it support and what kind of new mobile core topologies could be erected using this idea. Since the system was brand new and since such scalability tests are extremely time consuming, we focused on initial functionality proof points.

Cisco claimed that its ASR 5000-based mobile core could use the PCRF to implement throttling for different customer tiers, so we set out to test just that. Cisco’s mobile setup was in a different lab than our cloud test bed and we decided not to move it. If the PCRF can run in the cloud, then it should certainly be able to run in our cloud test bed to a remote mobile core and test setup. Ixia helped us to bring an extra XM2 tester over to the building where Cisco’s ASR 5000 was and we set up the test. Cisco configured a single ASR 5000 to do the work of the Packet Gateway (PGW) and Serving Gateway (SGW) in a Long Term Evolution (LTE) scenario.

Ixia’s IxLoad was used to emulate the Mobility Management Entity (MME) on one port connected to the ASR 5000, with the base station and clients behind it, and the emulated Web servers with content on a second port, also connected to the ASR 5000. In the cloud, the PCRF was set up with three virtual machines. One had Cisco's Inteligent Policy and Control Function (IPCF -- Cisco’s implementation of the 3GPP-defined PCRF) installed; the second ran Cisco's Subscriber Service Controller (SSC), which held the database of subscriber data, and the third virtual machine ran Cisco's Policy Provisioning Tool (PPT) and the Mobility Unified Reporting (MUR) tool.

Before we looked at throttling, as a sanity check, we ensured that we could establish both default and dedicated bearers to up to 50 subscribers. Since only data traffic was going to be used in this test we only configured default bearer per subscriber.

Throttling Mobile Subscribers
To test the throttling feature we configured three subscribers -- one bronze, one silver, one gold. Cisco’s ASR 5000 and PCRF categorized them based on IMSI ranges. Each subscriber was configured to create an HTTP session with the emulated server, attempting to reach as high a data rate as possible. Each subscriber type had a different bandwidth policy assigned: Gold subscribers received 4Mbit/s per bearer, Silver subscribers received 3Mbit/s and Bronze subscribers received 2Mbit/s. Each subscriber had two additional rules assigned. The first rule was a traffic volume limit of 50MB. Once this limit was reached, each subscriber bandwidth was throttled some more: Gold subscribers were throttled back to to 2Mbit/s, Silver to 1.5Mbit/s, and Bronze to 1Mbit/s. We cleared the volume usage on each subscriber and tested each one at a time. The graph below shows that each subscriber was throttled approximately as expected. The behavior of each line shows that the ASR 5000 would allow a burst before dropping, and Ixia’s TCP sessions slowly learning to home in on the rate it could consistently get.

Once the test was complete, Cisco mentioned it is also working on enabling dynamic policies -- the reconfiguration of how the ASR 5000 throttles traffic based on some condition. One of such conditions was when a specific Access Point Name (APN) crosses a bandwidth threshold as a percentage of how much bandwidth the ASR 5000 was seeing in total. Another dynamic policy was to limit specific protocol if traffic from this protocol exceeds a given percentage amongst the total traffic, which could be used to throttle P2P and YouTube traffic, for example.

Cisco explained that operators have asked for such features. One example we heard from Cisco was that operators would like to be able to limit peer-to-peer traffic, dynamically ensuring that it never reaches a high percentage of the total traffic in the mobile network and that it doesn't reach a high data rate. Such functions could also be performed in the mobile core firewall or DPI devices for example, but putting them directly into the mobile gateway enables mobile operators to register the offender (since the gateway has an IMSI and account association). Interesting, powerful, and potentially a can of worms, depending on how it's used.

These functions are also where the MUR and PPT come into play. Cisco explained that the MUR should normally poll live traffic statistics from the ASR 5000 and the PPT will send the new configuration to the ASR 5000 if they see the conditions met. At the time of the test, the ASR 5000 polling was not yet implemented so Cisco was using some in house scripts for their own testing to manually update the MUR with traffic statistics. In this concept demonstration, we observed that when these scripts were used in accordance with the APNs or protocols we configured with the Ixia equipment, the throttling rates indeed changed.

We validated that the PCRF worked from its installation in the data center. It controlled the mobile gateway located across campus and applied policies to subscribers both statically and dynamically. The question on mobile service provider minds is very often: "Will it scale?" This question is left unanswered at the moment since a scaling test, in the policy and control area, is a completely different beast, one that we did invite Cisco to take on. Meanwhile we also welcome Cisco's ideas for using the PCRF in the cloud -- ideas that increase the potential scalability, and optimize both agility and access to the data.

Next Page: Conclusion: Cloud Intelligent Networks
Previous Page: DHCPv6 in the Cloud

Back to the Cisco Test Main Page

(0)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
Light Reading’s Upskill U is a FREE, interactive, online educational resource that delivers must-have education on themes that relate to the overall business transformation taking place in the communications industry.
Wednesday, October 26, 1:00PM EDT
Security: Tackling DDoS
Gary Sockrider, Principal Security Technologist, Arbor Networks
Friday, October 28, 1:00PM EDT
Security: The Plusses and Minuses of Open Source Software
Nick Feamster, Acting Director, Center for Information Technology Policy, Princeton University
Wednesday, November 16, 1:00PM EST
SDN 101
John Isch, Practice Director, Network & Voice, Orange Business Services
Friday, November 18, 1:00PM EST
SDN & Open Source
Christopher W. Rice, Senior Vice President of AT&T Labs, Domain 2.0 Architecture and Design
in association with:
From The Founder
Light Reading today starts a new voyage as part of a larger Enterprise.
Flash Poll
Live Streaming Video
Charting the CSP's Future
Six different communications service providers join to debate their visions of the future CSP, following a landmark presentation from AT&T on its massive virtualization efforts and a look back on where the telecom industry has been and where it's going from two industry veterans.
LRTV Custom TV
Next-Generation Technology Beyond DOCSIS 3.1

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Liu Jianhua speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Hybrid Video Solutions to Change TV, Change Future

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Ian Locke speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Huawei Future-Oriented Giga Coax Network

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Allen Wang speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Huawei at SCTE 2016

10|20|16   |     |   (0) comments

Join Alan Breznick of Light Reading and take a sneak peek at the Huawei booth at SCTE 2016.
LRTV Custom TV
Assuring Network Quality in a Rapidly Changing Environment

10|20|16   |     |   (0) comments

As the rate of change and complexity increases in agile networks, the importance of introducing DevOps methodologies for integrating active test and assurance solutions throughout the full service lifecycle becomes critical to ensure that customers are experiencing the service quality they demand. The industry landscape is changing, and software-based test and ...
Telecom Innovators Video Showcase
A10 Networks on Service Providers' Industry Needs

10|20|16   |     |   (0) comments

Light Reading's Steve Saunders hears how A10 enables service providers to accelerate, secure and optimize their application delivery to drive down costs, enhance service availability, and better respond to customer requirements, so they can improve customer satisfaction, monetize their network, and grow revenues.
LRTV Custom TV
New NFV Use Cases for Cable TV

10|19|16   |     |   (0) comments

A large number of NFV use cases are focused on the enterprise domain, looking at virtualization of customer-premises equipment (CPE). To date, there has been little focus on the use cases and business case for virtualization of the video content delivery networks required to deliver unicast and streaming video to consumers. Amdocs commissioned Analysys Mason to ...
Women in Comms Introduction Videos
Meet the Future Workforce: New Faces, Expectations & Motivations

10|19|16   |   5:33   |   (1) comment

Millennials and their younger peers, Gen Z, expect more out of their network and more out of their work. Intel's Lynn Comp shares how the industry can prepare for this new generation of workers.
LRTV Custom TV
ZTE Global Services User Congress 2016 Highlights

10|19|16   |     |   (0) comments

ZTE held its 2nd Global Service User Conference in Dusseldorf on October 13-14. Representatives from network operators, leading industry analysts and ZTE senior expertsattended the event, exploring the best practice in managed services and the vision to transform network operations into the operations center of the future (OpCF) in the software-defined networking ...
LRTV Custom TV
Cliff Grossner on Cloud & Network Synergy From Carrier Service

10|18|16   |     |   (0) comments

Local carriers offer the collaborated cloud and network service that benefits from their understanding of the regulations operating in different vertical markets.
In this interview, Cliff Grossner from IHS Technology talks about how this advanced service can support business agility and flexibility.
LRTV Custom TV
VeEX: Live from SCTE Cable-Tec Expo 2016

10|17|16   |     |   (0) comments

Cyrille Morelle, VeEX's President and CEO, talks with Light Reading's Alan Breznick live from the SCTE Cable-Tec Expo 2016. They discuss DOCSIS 3.1 technology, deployments and early lessons learned. New products on display include the CX350s-D3.1, CX380s-D3.1, CX310, AT2500-3G, FX150 OTDR and MTT WiFI Air Expert.
LRTV Custom TV
Smith Micro's Carrier-Grade WiFi Component

10|17|16   |     |   (0) comments

Join Carol Wilson of Light Reading as she interviews the CTO of Smith Micro, Dave Sperling.
Upcoming Live Events
November 3, 2016, The Montcalm Marble Arch, London
November 30, 2016, The Westin Times Square, New York City
December 1, 2016, The Westin Times Square, New York, NY
December 6-8, 2016, The Westin Excelsior, Rome
May 16-17, 2017, Austin Convention Center, Austin, TX
All Upcoming Live Events
Hot Topics
Attacks Have Major Internet Sites on the Ropes
Brian Santo, Senior editor, Test & Measurement / Components, Light Reading, 10/21/2016
Verizon Wants More Data on Yahoo Breach
Alan Breznick, Cable/Video Practice Leader, Light Reading, 10/20/2016
WiCipedia: Grace Hopper Promotes Diversity, Girl Scouts Code & How to Thrive
Eryn Leavens, Special Features & Copy Editor, 10/21/2016
Layer3 TV Comes to Town, Hints at Future
Mari Silbey, Senior Editor, Cable/Video, 10/21/2016
Telecom Italia Plots Digital 'Overlay,' Not Transformation
Iain Morris, News Editor, 10/17/2016
Like Us on Facebook
Twitter Feed
BETWEEN THE CEOs - Executive Interviews
Join us for an in-depth interview between Steve Saunders of Light Reading and Alexis Black Bjorlin of Intel as they discuss the release of the company's Silicon Photonics platform, its performance, long-term prospects, customer expectations and much more.
There's no question that, come 2020, 5G technology will turn the world's conception of what mobile networking is on its head. Within the world of 5G development, Dr. ...
Animals with Phones
Live Digital Audio

A vital part of increasing the number of women in comms is transforming the ways companies can support and empower women. While progressive company policies that support both men and women in achieving work-life balance are a step in the right direction, creating a company culture that supports those policies can at times be more challenging.

During this show, we'll talk to Lynn Comp, Senior Director of Industry and Sales Enabling (ISE) in the Network Platforms Group at Intel, about why those challenges exist and how companies can overcome them. She'll provide insight into how Intel has worked to create a culture that supports work-life balance, and provide steps and guidance for other companies wishing to do the same. We will also leave plenty of time to get your questions answered live on the air.