Protocol Testing of the VoIP Network

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Protocol Testing of the VoIP Network
August 2005
Mike Mikkelsen Business Development
Mgr. Mike.Mikkelsen_at_exfo.com
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Protocol Testing of the VoIP Network

• Ethernet Service Revenues
• 2004 2.5 Billion Dollar market
• 2005 5.0 Billion Dollar Market
• 2006-09 22 Billion Dollar Market
• 98 of business/home LANs are Ethernet

Source Infonetics Lightwave
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Protocol Testing of the VoIP Network

• Market Drivers
• VoIP and IP Video growth
• Bandwidth demand steadily increasing
• Ethernet is more cost effective and scalable
• VLAN segmentation allows for right sizing of
  circuits on a per customer basis

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Benefits of Metro EthernetOperational Expense
Savings

• Metro Ethernet Forum worked with 36 service
  providers to identify actual OpEx savings for
  Metro Ethernet compared to legacy Private Line,
  Frame Relay and ATM services
• Metro Ethernet services reduced OpEx by 23.
• Typically OpEx represents 71 of service provider
  budget
• Savings drops right to the bottom line
• Primary Drivers
• Initial Provisioning 13 - 22 savings
• Bandwidth Upgrades 66 - 83 savings

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Protocol Testing of the VoIP Network

• VoIP is a LAN application
• -Businesses and Home users will experience the
  same issues
• -VoIP Quality issues
• -Ethernet service reliability
• -SLA Contracts

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Market SegmentationBandwidth Management and
Network Quality
Critical Packets

• Real Time Imaging
• Voice over IP
• Fortune 100
• Financial Enterprises
• SLAs
• Network Security

Carrier-Class Ethernet
Bandwidth Management
Best Effort Services
ResidentialLow Value

• Residential Browsers
• Non-Critical Data

Network Quality
Low Reliability
High Reliability

• Direct Connect Architecture

• Proactive Management
• Service Restoration
• Performance Monitoring
• Facility Management

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VoIP transport testing

• The Trend
• As of December 2004, Ethernet became the
  preferred enterprise data-access technology,
  surpassing ATM frame relay
• Ethernet is attractive because it offers easy
  migration to services such as VPNs, remote data
  storage, and VoIP
• VoIP-based PBX sales are steadily growing in
  popularity as customer confidence increases

Enterprise Telephony Services Revenue
40 growth In 2004
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VoIP transport testing

• The Challenge
• Customers demand toll-quality voice services, or
  they will not migrate to VoIP
• Operators must offer service guarantees SLAs, to
  attract customers
• Not meeting an SLA means
• poor customer satisfaction
• increased maintenance spending (OpEx)
• direct financial penalties
• The Solution
• Turn-up testing of the Ethernet link is required
• Performance Testing (RFC-2544)
• VoIP Packet Jitter
• VoIP MOS Score

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VoIP transport testing

• VoIP Realities
• Packet-switched networks were not originally
  designed to transmit voice
• VoIP packets have to share bandwidth with other
  data services
• FTP, remote backup, internet access, email, video
  streaming, etc.
• Bandwidth intensive applications can choke VoIP
  traffic, resulting in poor voice quality or
  dropped calls when information is delayed or lost
• Multi-stream scenarios should be tested during
  commissioning
• Network parameters (VLAN priorities, IP QoS
  levels, throughput, etc.) can be adjusted by a
  network operator to provide adequate priority and
  bandwidth for VoIP packets.

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VoIP transport testing

• The 5 critical VoIP test parameters
• Before turning up a VoIP service, the Ethernet
  access line should be tested for performance with
  a focus on 5 key parameters

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VoIP transport testing

• Troubleshooting
• These same 5 key parameters are valuable for
  troubleshooting during or after deployment
• Most of the parameters indicate more than one
  problem, which often occur simultaneously
• The duration and combination of parameters points
  to different network problems, allowing
  deployment teams to quickly optimize a link.

• Most common causes of VoIP QoS issues
• Route flapping when a network frequently
  changes the path packets use to get to their
  final destination. This can be caused by
  congested networks or poor traffic engineering.
• Access link congestion when VoIP packets are
  not given dedicated bandwidth or sufficient
  priority, other applications can degrade voice
  quality.
• Backhaul congestion when bandwidth is limited
  during the aggregation of access lines this is
  often indicated by high latency and low
  throughput.

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VoIP transport testing

• Simulating Real Traffic Patterns
• Test equipment must offer various ways of
  simulating real customer traffic when
  commissioning or testing a link
• Multi-stream traffic generation measure one
  stream while varying others
• VLAN and Flow Control replicate customer
  network parameters

• The Skinny on MOS
• Mean Opinion Score (MOS) is a test parameter
  which is calculated from the 5 critical VoIP test
  parameters shown previously
• MOS attempts to describe the quality of a VoIP
  call as perceived by an actual listener, and
  accounts for echo, drop-outs, fidelity, and
  listening strain
• MOS is useful to confirm that a service has been
  commissioned properly, BUT as an aggregate
  parameter, does not offer enough info to qualify
  a link or service
• A MOS test can pass even if an SLA is in
  violation
• e.g. poor throughput, but good latency and packet
  jitter help to maintain call quality SLA
  penalties will be applied to the throughput
  problem

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Protocol Testing of the VoIP Network

• Service Providers Must be Competitive
• - Maintain SLAs
• - Demonstrate Ethernet service reliability
• - Identify/Correct VoIP Quality issues fast
• Must employ Scalable cost-effective test tools
  and practices, in order to maintain SLAs /
  customer satisfaction.

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Test Equipment

• Turn-up and Installation
• Performance Testing (RFC-2544)
• VoIP Frame Jitter (RFC-3393)
• VoIP MOS (Mean Opinion Score)
• Troubleshooting
• Bit Error Rate (BER) testing
• VoIP MOS testing
• Service Disruption Measurements
• Framed BER Measurements
• Multi stream generation application across VLANs

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Jitter for Voice

• RFC-3393 defines how to test for Jitter.
• Three pre-defined VoIP type frames
• Jitter measurements should not exceed 30ms for
  acceptable VoIP

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Jitter for Video

• Definitions for user defined jitter testing for
  Video

Source PictureTel Managing IP Video Streaming
Bandwidth
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Test Set Configurations Dual Test Set

• Also known as Head to Head testing

• Ideal for
• End to End Testing

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Test Set Configurations Single Port Loopback

• One Test Set Solution
• Port 1 TX into Port 1 RX

• Ideal for
• DWDM systems
• End to End testing with end devices that can loop
  back into the same port

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End-to-End and End-to-Core testing
Remote Testing

• SLA Performance requirements
• Throughput Jitter
• Latency MOS for VoIP
• Frame Loss

Internet
Metro Network
Gigabit Ethernet
Gigabit Ethernet
Access Network
10/100Base-T
10/100Base-T
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Ethernet ServicesOperations, Administration and
Management
Ethernet in the First Mile

• Ethernet Network Interface Unit
• 802.3ah Compatible

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IEEE 802.3ah Ethernet in the First MileEthernet
Operations, Administration and Management

• IEEE standard out for ballot
• Approved June 2004
• Creates OAM sub layer in the data link

• Operational functionality defined within
  standard
• Remote loopbacks
• Remote failure indications
• Link monitoring
• Event notification and diagnostics
• Historical performance parameters
• All in-band management

How can this new standard be leveraged in
emerging networks?
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Ethernet Network Interface Unit (ENIU)
Feature Benefits Remote
troubleshooting ? Fewer truck rolls
Single-ended testing ? Restore services
faster Proactive network management ? Reduce
network downtime One-Man operation ?
Increase network availability ? Easily
integrated into existing operations

• The Remote Ethernet Testing Solution
• ENIUs installed at customer / network demarcation
  points
• Test sets remotely communicates with the ENIU
• Monitor link behavior retrieve link / customer
  usage statistics
• Enable loopback for end-end Ethernet line
  testing
• Remote troubleshooting SLA validation
• Client / Provider problem sectioning/resolution
• Commissioning new services

NOC
HeadEnd
Remote Management
Ethernet testhead modules
Router
Ethernet Testset
Ethernet Switch
Metro Network SONET/SDH/DWDM
Router
ENIU
Customer Premises
Ethernet Switch
www.adc.com
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Ethernet Network Interface Unit (ENIU)

• Multiple interface solutions of 10/100/1000 Mbps
• Electrical to Optical UTP to Singlemode or
  Multimode fiber
• Electrical to Electrical UTP to UTP
• Optical to Optical
• Bandwidth provisional
• In-band loopback control
• Loss of Power circuit cut-through
• Local craft interface RS-232
• Provisioning
• Historical performance data
• Alarm management
• AC or DC power

Loss of signal (LOS) CRC Error Threshold Errored
Symbol Period Event Threshold Errored Frame
Event Errored Frame Event Threshold Errored Frame
Second Summary Event Threshold Over
Temperature Optical Power Threshold
www.adc.com
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Ethernet Network Interface Unit

• IEEE802.3ah approved in June 2004. Leverage new
  technology opportunity
• Ethernet NIU is the next step in the
  customer-driven evolution into active Ethernet
  products
• Proactive management of Ethernet services
• Remote visibility of system/circuit performance
• Single end testing
• Reduce dispatches for troubleshooting and turn-up
• Demarcation Interfaces E/E, E/O, O/O
• Competitive Differentiators
• Flexibility in network and customer interfaces
• Scalable intelligence

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QUESTIONS
Thank You!