How a Tier 1
Global Service
Provider solved
a major issue
using Viavi’s
EtherASSURE™
LTE Segmentation
Solution
Troubleshooting Ethernet Networks with PacketPortal Intelligent Visibility, Segmentation, and
Micro Burst Reporting
Mobile networks have evolved (with 4G technologies such as LTE) but
This industry-leading solution extends the capabilities of traditional
must still carry legacy 2G and 3G traffic. Data volume and signaling
performance monitoring and test standards based on synthetic traffic
growth mixed with new users, terminals, and applications are generating
by augmenting the results with measurements based on real-time
higher loads and dynamically changing traffic patterns that affect the
live customer traffic. This empowers operators with the intelligence
network and its resources in unique ways. It is paramount to have full
necessary to better control their network QoS, backhaul costs, and
visibility into all aspects of network utilization and performance to
efficiency with an end-to-end view of monitoring, real-time packet
tackle the negative effects rapid traffic growth can create.
captures, segmented hop-by-hop performance metrics, and traffic-
The Viavi EtherASSURE LTE Segmentation Solution utilizes live trafficbased performance monitoring with the ability to segment networks on
based views of network and application performance—all based on real
customer use and traffic flow.
a per-hop basis and provides extremely accurate live traffic reporting
down to the micro-second basis. This provides service providers with the
visibility needed for operators to improve margins and QoE for better
customer experience.
Case Study
Major Customer Challenge
What We Learned
A major global tier 1 service provider was looking for a solution to
While troubleshooting the service provider’s UK network: with
get visibility into the performance of their backhaul network. They
PacketPortal in place, Viavi took a multidimensional view to test the
were blind to what was happening on the network – especially for
entire network that included 21 cell sites. The current monitoring
LTE networks and they needed visibility for planning purposes, to
solution was measuring the network with 15-minute resolution, so
manage quality during network rollout (test and turn up), and to drive
Viavi started its own tests at the same intervals and no problems
customer satisfaction and ensure they were meeting SLAs. The target
could be seen. Since PacketPortal has the ability to measure in much
application was initially focused on mobile backhaul but they also
higher resolution, Viavi began to test in five-minute, one-minute,
plan to eventually deploy the solution for delivering fixed network
30-second, and one-second resolution.
and Enterprise services. The solution will also be used in network
sharing scenarios to ensure they are getting a fair share of what they
are paying for.
Although the root cause of the dropped calls did not immediately
surface, a new discovery was made. At 15-minute intervals, the
network appeared to be working well under its current capacity,
At the same time the service provider’s UK group experienced
peaking at no more than 14% of capacity. But when the monitoring
problems when 4G data was introduced into their wireless network,
intervals were decreased to one second, Viavi discovered the network
the failure rates for 2G calls increased by more than 3% resulting in
was peaking to as much as 100% of its capacity due to 4G data
customer experience issues. According to the monitoring solutions
traffic. This was an important discovery for the service provider as it
that were in place, the network was showing indications of a problem
now knew its network was much more susceptible to traffic spikes
with 2G, however, 4G was normal so they turned to Viavi to help with
(bursting) than originally thought.
identifying where the problem might be.
The Viavi Answer
With this new information in hand, Viavi began testing a cell site
to see how it would react to such bursts. The cell site performed as
expected under normal loads, but when synthetic data was added
to simulate a traffic spike, problems began to arise and it was found
In order to remotely perform segmented fault isolation and to quickly
find the specific problematic path, technology, or network elements,
Viavi recommended the EtherASSURE LTE Segmentation and
PacketPortal® solutions. The solution utilizes distributed PacketPortal
that one of the network elements was not performing correctly.
The element was incorrectly prioritizing mobile data traffic on the
link, causing it to drop not only 2G calls, but some 3G calls as well.
Normally, the element should throttle down the peak data traffic to
Intelligent Visibility (IV) smart SFPs to enable remote, segmented fault
prevent this from happening since voice calls get priority.
isolation without the need for any technician dispatch.
Viavi was able to not only demarcate the problem and segment it
The Viavi EtherASSURE LTE Segmentation and PacketPortal solutions
to a localized element; we also helped them discover that 15-minute
provide a comprehensive, flexible and cost-effective end-to-end
visibility solution for Ethernet assurance. It includes; the EtherASSURE
Solution for Segmentation and Performance Management with Live
measurement resolution wasn’t working for today’s highly volatile
traffic patterns. PacketPortal, along with active testing, was able to
give much more insight into what the network was doing and how it
Traffic, the QT-600 or virtual QT test heads, the PacketPortal JMEP
was performing in real-time than their previous visibility.
smart SFPs, and the PacketPortal IV smart SFPs.
The service provider was able to update the network element and
has assured its network performance is meeting SLAs and customer
expectations.
2 Troubleshooting Ethernet Networks
Summary
The service provider recognized the unique ability to get segmented
hop-by-hop visibility into real user traffic performance, enabled by
PacketPortal. Viavi was able to demonstrate the real value of this
solution by quickly finding the root cause of the dramatic (3%) spike
in 2G dropped calls in a heterogeneous network. This had been the
number one insomnia topic for the service provider’s management for
months!
The service provider was particularly pleased with:
Figure 1 Network perfomance views based on real-time packet catures
•
Micro Burst detection with reporting down to a micro second
basis - critical with 4G traffic
•
Transparent probing and responders as part of the network
with minimal footprint using JMEP and PPIV smart SFPs – a KEY
requirement
•
Minimal network design impact and operation within MPLS
without re-design
•
Smart SFPs added with minimal network disturbance
•
In-band management with no additional network design
•
Interoperation with existing field portable equipment
After the above initial network troubleshooting success, the service
Figure 2 Real-time traffic intelligence for better network QoS
provider issued Viavi a global contract covering all worldwide network
properties, which account for more than 400 million subscribers.
Figure 3 End-to-end monitoring and perfomance views based
on real-time traffic
Contact Us
+1 844 GO VIAVI
(+1 844 468 4284)
To reach the Viavi office nearest you,
visit viavisolutions.com/contacts.
© 2016 Viavi Solutions Inc.
Product specifications and descriptions in this
document are subject to change without notice.
Troubleshooting – ethernetnetworks-cs-sas-nse-ae
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