wireless network analysis 101 vofi (voice over wi-fi)

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Jay Botelho Director of Product Management WildPackets [email protected] Follow me @jaybotelho

Wireless Network Analysis 101 VoFi (Voice over Wi-Fi)

© WildPackets, Inc. #wp_wireless Wireless Network Analysis 101 - VoFi

Administration

• All callers are on mute ‒ If you have problems, please let us know via the Chat window

• There will be Q&A ‒ Feel free to type a question at any time

• Slides and recording will be available ‒ Notification within 48 hours via a follow-up email

2


Agenda

• Why VoFi? Why now? • Collecting data for VoFi analysis • Assessing the WLAN landscape for VoFi • Using VoIP metrics with VoFi • VoIP/VoFi – one more call and you’re over the cliff • Demo – anatomy of a VoFi call • Key wireless factors in VoFi quality • Corporate overview • Product line overview

3


Why VoFi? Why Now?

4


Why VoFi?

Quality Convenience Cost


Why Now?

• Smart phones support 802.11 - period • VoFi systems have already found wide acceptance in

some areas: manufacturing, medical, retail • The Wi-Fi alliance supports 2 certification programs:

‒ Voice-Enterprise: 44 certified products ‒ Voice Personal: 69 certified products

“802.11ac is being pushed into smart phones by key carriers’ device requirements that are in sync with 802.11ac hotspot

plans for more robust Wi-Fi offloading.” ABI Research


Collecting Data for VoFi Analysis

7


Flexible Data Collection - Portable

• Network analysis software (OmniPeek) with supported NIC

‒ 802.11a/b/g/n USB adapter ‒ VoIP, VoFi, full Expert Analysis ‒ Simultaneous Wired and Wireless Capture

• Multi-channel aggregation

‒ 802.11a/b/g/n USB adapters ‒ USB hub ‒ Powered USB hub for captures on 3 or more channels


9


Remote Captures with OmniEngine

Remote Software Probe for 24x7

Operation

Using USB Adapters Using APs

RemotePcap Custom Remote Adapters


Assessing the Wireless Landscape

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It’s All One Network

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And It’s Wireless and Wired

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Using VoIP Metrics with VoFi

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Key RTP (VoIP/VoFi) Issues

CAMP IT Pinpointing the Problem 15

Jitter Latency

Packet Loss


Assessing the Monster's Impact • While traditional network applications are very tolerant of jitter,

latency, and even some degree of packet loss, VoIP/Video/VoFi are very sensitive to these troubles

• Levels of jitter, latency, and packet loss that would be easily tolerated on a data network can be devastating on a converged VoIP/Video network

• Pre- and post-deployment network assessments are critical ‒ You must understand your network’s ability to accommodate VoIP

• Current latency, jitter, and packet loss • QoS capabilities • Current bandwidth utilization (is there any room for VoIP)

‒ You must maintain a constant vigil after deployment to watch for imminent troubles


Latency Queue Latency & Decision Latency

Network Propagation

Delay

Encoding / Decoding Compression / Decompression

Jitter Buffer Latency

0 ms

100 ms

200 ms

300 ms

400 ms

500 ms

600 ms

700 ms

800 ms

The ITU recommends a maximum one-way delay of 150 ms for

VoIP


Latency's Effects • Talkover

‒ Occurs when excessive latency delays audio – Conversation cadence is not natural or comfortable – Callers feel as if they must “push to talk” or say “over” to control the

conversation

• Echo ‒ The speaker’s voice feeds back into the listener’s microphone ‒ The speaker then hears his own voice returning from the listener’s end,

but delayed due to latency ‒ Most callers find it difficult to maintain normal speech when echo delay

is prolonged ‒ Some VoIP systems attempt to cancel echo, but are not always

successful

High latency may also cause additional troubles such as loss of synchronization between audio and video for multimedia sessions.


Jitter • Jitter is the variance in packet delivery intervals to the listener

• Jitter buffer adds additional delay to voice reaching the ear piece in case other packets need to catch up

• Packets delayed too long in the network are not allowed to enter the jitter buffer

Packets delayed more than the buffer delay (100 ms as an example) are dropped

. . .. .. . . ........ ......

Packets are buffered and delayed at the Receiver

The “jitter” buffer releases a G.711 packet every 20 ms

A G.711 packet sent every 20 ms

Packet jitter and drops

3 1

2

4


Jitter's Effects

• Jitter causes weird “sound effects” that vary with jitter severity and environmental factors

• Examples include: ‒ Static ‒ Stuttering or uneven audio – abnormal speech rhythm ‒ For multimedia systems, video may be “jerky” or irregular

• If jitter levels are high, packet loss can result ‒ In some cases, severe jitter may sound similar to packet loss,

even if no packets are actually dropped


Packet Loss and Effects • Most commonly caused by:

‒ Packet dropped due to physical layer corruption ‒ Congestion without adequate QoS provisions ‒ Jitter buffer discards due to excessive latency

• Causes missing sounds, syllables, words, or phrases ‒ DSP algorithms may compensate for up to 30 ms of missing

data ‒ More than 30 ms of missing audio (e.g. 2 RTP packets for

G.711) is noticeable by listeners

• Losing only a few packets can still be very noticeable ‒ Loss rates ≥ 2% will have a strong impact on quality ‒ Losses of 5 – 10% make calls all but intolerable ‒ Bursty periods of packet loss are worse than more dispersed

loss


Quality Scoring for VoIP

• Mean Opinion Score (MOS) – several flavors ‒ Algorithmic simulation of subjective audio assessment ‒ Most commonly used varieties are MOS-LQ (listening quality)

and MOS-CQ (conversational quality) ‒ Possible range of 1 (poor) to 5 (excellent) ‒ Maximum possible MOS = 4.4 with G.711 ‒ Typical range in most networks is 3.5 – 4.2

• R-Factor – several flavors ‒ Based on latency, jitter, packet loss, bit rate, and signal-to-noise

ratio, codec effects (for low bit-rate codecs) • The ITU algorithms consider about 20 quality inputs

‒ Possible range of 0 (poor) to 100 (excellent) ‒ Provides LQ, CQ, and other score variants


Crunching the Voice Score OmniPeek does the hard part…

… so you can see the bottom line Source: ITU Recommendation G.108 – E-Model Guidelines


A Picture is Worth a 1000 Words • A graph of latency, jitter, or

packet loss can speak volumes about network health, either for proactive or reactive troubleshooting

• Overlaying graphs with network utilization or total throughput can reveal even more about the causes of VoIP troubles

0.000.501.001.502.002.503.003.504.004.505.00

8:45

9:15

9:45

10:1

5

10:4

5

11:1

5

11:4

5

12:1

5

12:4

5

13:1

5

13:4

5

14:1

5

14:4

5

15:1

5

15:4

5

16:1

5

16:4

5

17:1

5

Mea

n O

pini

on S

core

Time

MOS


Video vs. VoIP

• Video is more difficult to manage than voice ‒ more “bursty” ‒ bandwidth intensive

‒ more sensitive to latency, jitter, and packet loss

‒ Includes several different applications with distinct demands

• Video packets vary greatly in size • Tremendously compressed amount of visual information (99%

compression ratio typical) • One HD video stream can consume up to 20Mbps of bandwidth • Video apps require millisecond-level network service recovery


One More Call and You're over the Cliff


The Impact of "Just One More Call"

• Although a network link may be able to support a number of concurrent calls, one additional call is often enough to cause quality problems…

x1113

x2111

x1112

x1111

1st Call

2nd Call

3rd Call x2112

x2113

Example: The WAN can support 2 simultaneous calls. What happens when a third call is attempted???

Call #3 Causes Poor Quality for ALL Calls


Demo: Anatomy of a VoFi Call


Packet-by-Packet

VoFi Call

Wired VoIP Call


Just the Stats, Mam


Key WLAN Factors for VoFi


Additional Factors to Consider

• Interference • CRCs vs. retransmissions • QoS (WMM) • Roaming • AP load

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Quantitative Interference Impacts on VoFi

Source: Farpoint Group


Quantitative Interference Impacts on VidFi

Source: Farpoint Group


CRCs vs. Retransmissions

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Ready for QoS/WMM?

• QoS provisions are based on the “weakest link” concept

‒ If any device in a data path does not support QoS, then media streams will not be afforded the preference they require for good performance

• Pre-deployment assessment must ensure that ALL devices can recognize and respond to QoS parameters in packet headers

‒ Switches, routers, firewalls, proxies, and any other devices that touch RTP packets must be “VoIP-friendly”


Client Roaming

• Occurs when a handset moves out of range of one AP and into another – typically changes channel

• Client roaming = Fast Basic Service Set (BSS) Transition

• Legacy systems deal poorly with roaming – they’re not fast enough

• Standards help: ‒ 802.11i with Opportunistic Key Caching (OKC) ‒ 802.11r-2008 – Fast BSS Transition ‒ 802.11k-2008 – Radio Resource Measurement of WLANs


Roaming in Action

• Multichannel Analysis • Roaming Analysis

‒ Detailed and accurate measurements from many perspectives • End-user and device

manufacturer ‒ Summary data for roaming from

each AP or each client


AP Load

39


Q&A

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WildPackets Corporate Overview

Optimizing Network and Application Performance


Corporate Background • Experts in network monitoring, analysis, and troubleshooting

‒ Founded: 1990 / Headquarters: Walnut Creek, CA ‒ Offices throughout the US, EMEA, and APAC

• Customers spanning leading edge organizations ‒ Mid-market and enterprise lines of business ‒ Financial, manufacturing, ISPs, major federal agencies,

state and local governments, universities ‒ Over 7,000 customers / 60+ countries / 80% of Fortune 1,000

• Award-winning solutions that improve network performance ‒ Internet Telephony, Network Magazine, Network Computing awards ‒ United States Patent 5,787,253 issued July 28, 1998

• “Apparatus and Method of Analyzing Internet Activity”

Presenter

Presentation Notes

Founded in 1990, WildPackets develops network and application analysis solutions that enable organizations of all sizes to analyze, troubleshoot, optimize, and secure their wired and wireless networks, improving network and application performance. Our patented technology emerged in the early nineties with the award-winning EtherPeek network protocol analyzer. Today OmniPeek encompasses troubleshooting and analysis, of wired and wireless networks including 10 gigabit, 802.11n, and as well as VoIP and application performance analysis. WildPackets products are sold in over 60 countries through a broad network of channel and strategic partners. Our customers span all industrial sectors, including 80% of the Fortune 1000, including Boeing, Chrysler, Cisco, Comcast, EDS, Hewlett-Packard, Microsoft, Motorola, Nationwide, Siemens, Qualcomm, and Deutsche Bank. Strategic partners include Aruba, Atheros, Cisco, 3Com, Intel, Net Optics, and Gigamon.


Why Our Customers Need Us

• VoIP, video, cloud, virtualization, and key business applications are saturating critical network services

• Evolving network technologies create discontinuities ‒ 1 Gig 10 Gig 40 Gig 100 Gig networks ‒ Wireless, BYOD initiatives

• Users and business can not tolerate network problems for mission critical services

Increasing demand for better real-time network visibility, network analytics, network forensics, and DPI


How We Create Value

We provide innovative, industry-leading, real-time network performance management solutions

‒ Easy-to-use, easy-to-learn user interface ‒ Uniquely extensible solutions ‒ Wireless network leadership ‒ Detailed analytics related to network applications ‒ Fastest network traffic capture appliance in its class ‒ Technical superiority at competitive price point

WildPackets has continually advanced its solution to meet the needs of its customers


Unprecedented Network Visibility

ROOT-CAUSE ANALYSIS

OmniPeek network analyzer performs deep packet inspection and can reconstruct all network activity, including e-mail and IM, as well as analyze VoIP and video traffic quality.

PINPOINT NETWORK ISSUES ANYWHERE

Omnipliance Portable can rapidly identify and troubleshoot issues before they become major problems—wired or wireless—down the hall or across the globe.

UNDERSTAND END-USER PERFORMANCE Omnipliance network analysis and recorder appliances monitor and analyze performance across critical network segments, virtual environments, and remote sites.

NETWORK HEALTH

WatchPoint can manage and report on key device performance and availability across the entire network, from anywhere on the network.

GLOBAL

DISTRIBUTED

PORTABLE

DPI


A History of Innovation

2003 Distributed real-time

troubleshooting

2001 • First 802.11 wireless analyzer • First network analyzer with automated expert analysis

2005 Combined distributed network and VoIP network analysis

2008 Enterprise-wide

Monitoring and Reporting

2009 Innovative dashboard with drill-down for VoIP and video

2012 • Capture, record, and

analyze from 40G network segments

• First wireless network analyzer to support

801.11ac, k, r, u, v, w

2011 • Total visibility with zero packet loss • First wireless network analyzer to support capture and analysis of 802.11n 3-stream wireless

2010 First to achieve 11

Gbps sustained capture-to-disk

2013 Industry leading

network analysis and

recorder appliances


Product Line Overview


Omni Distributed Analysis Platform OmniPeek

Enterprise Packet Capture, Decode and Analysis

• Ethernet,1/10 Gigabit, 802.11, and voice and video over IP • Portable capture and OmniEngine console • Aggregate analysis data across multiple capture points

Omnipliance Network Analysis and Recorder Appliances

• High-performance packet capture and real-time analysis • Stream-to-disk for forensics analysis • Integrated OmniAdapter network analysis cards up to 40G

WatchPoint Centralized Enterprise Network Monitoring Appliance

• Aggregation and graphical display of network data • WildPackets OmniEngines • NetFlow and sFlow

Presenter

Presentation Notes

The OmniPeek Product Family offers both portable and distributed solutions for troubleshooting and optimizing enterprise networks and applications. OmniPeek network analyzers are used for portable analysis and troubleshooting, and the OmniPeek console connects to distributed OmniEngines, which analyze data at remote locations on the network. WatchPoint brings the data collection and Expert Analysis capabilities of the OmniPeek Product Family to an entirely new level by offering unprecedented visibility into network traffic trends and behavior across the entire enterprise.


Omni Distributed Analysis Platform Software and Turnkey Solutions

• Enterprise monitoring and reporting ‒ WatchPoint Server ‒ OmniFlow, NetFlow, and sFlow Collectors

• Network Analysis and Recorder Appliances ‒ Omnipliance CX, MX, TL ‒ Optional OmniStorage ‒ OmniAdapter analysis cards

• Distributed analysis software ‒ OmniPeek – Enterprise, Professional, Basic, Connect ‒ OmniPeek Remote Assistant ‒ OmniEngine Enterprise

• Portable solutions ‒ OmniPeek network analyzer ‒ Omnipliance Portable


OmniPeek Network Analyzer • Distributed analysis manager

– Connect to and configure distributed OmniEngines and Omnipliances,

• Comprehensive dashboards present network traffic in real-time – Vital statistics and graphs display trends on network and application

performance – Visual peer-map shows conversations and protocols – Intuitive drill-down for root-cause analysis of performance bottlenecks

• Visual Expert diagnosis speeds problem resolution – Packet and payload visualizers provide business-centric views

• Automated analytics and problem detection 24/7 – Easily create filters, triggers, scripting, advanced alarms, and alerts


OmniPeek Remote Assistant Distributed, End-user Packet Capture Made Simple

• Simple to deploy, simple to use ‒ Remote push, download from server, or even

email ‒ Simple user interface - eliminates confusion for

end user ‒ Full fidelity capture - see exactly what the PC

sees ‒ Wired or wireless

• Encrypted file ‒ Only the analyst can open it ‒ Different encryption keys for different locations

or customers

• Detailed client-side/end-user experience analysis

• Perfect for Tech Support or IT Desktop support

Trouble call from remote site - network response is slow.

User downloads and installs OmniPeek Remote. Encrypted capture

data sent back for analysis.

Network analyst uses OmniPeek Enterprise to quickly troubleshoot problem without leaving the office.


OmniWiFi USB WLAN Capture Adapter • A single device for all WLAN packet capture needs

• Driver included with Omni v7.9 CDs

• Tested and supported with OmniPeek and OmniEngine

• Product features: • USB device with extension cable • Dual band operation – 2.4GHz and 5GHz • Supports all standard international 802.11 channels (a/b/g/n) • Supports 802.11n - 3 transmit/receive streams (450Mbps) • Supports 802.11n 20MHz and 40MHz channel operation • Supports multi-channel aggregation and roaming

• Technical Details: ‒ Size (LWH): 6 inches, 1.5 inches, 5.5 inches ‒ Weight: 5.6 ounces

• Available via Amazon - $99/each

NOTE: • Capture ONLY – no network services • Does not capture 802.11ac


New Network Analysis and Recorder Appliances

Powerful Precise Affordable

The new family of WildPackets Network Analysis and Recorder appliances gives IT organizations powerful and precise analysis of

high-speed networks in an affordable solution with half the hardware footprint of rival offerings.


Powerful

‒ Fastest network recorder in its class! Captures traffic up to 20Gbps of real-world traffic (all size packet distribution)

‒ Scales up to 128 TB of storage ‒ Provides simultaneous real-time analysis and a comprehensive Forensic

Search that rapidly searches through terabytes of captured traffic for the details relevant to an investigation

Precise ‒ Captures complete network traffic, so you can analyze everything, not just

samples or high-level statistics ‒ Doesn’t drop packets or sacrifice accuracy for speed ‒ Supports rich, detailed analysis, including VoIP and video-over-IP traffic

Affordable ‒ Delivers outstanding price/performance (lower price; half the rack space) ‒ Allows mix of 1G/10G/40G interfaces without buying extra appliances ‒ Solutions start at $16,995

Your network is bigger and faster. Now your analysis solution is, too.


Omnipliance TL Industry Leading Network Analysis and Recorder Appliance

• Sets a new standard in capture-to-disk speeds ‒ 20Gbps sustained capture to disk rate with zero packet drop

• Best price/performance Network Analysis Appliance in the market

‒ 20Gbps with only one Omnipliance TL + OmniStorage ‒ Consuming less rack space, less cooling, less electrical power

• Most flexible network interface offering ‒ 1G/10G/40G interfaces supported in a single unit eliminates

additional unit requirement

• Most accurate real-time analytics ‒ Packet-based processing and analysis vs. inaccurate sample-

based calculation


WildPackets Network Analysis Recorder Appliances Price/Performance Solutions for Every Application

Portable Omnipliance CX Omnipliance MX Omnipliance TL

Ruggedized Troubleshooting

Less Demanding Networks Remote Offices

Datacenter Workhorse Easily Expandable

Enterprise, Highly-Utilized Networks

Aluminum chassis / 17” LCD 1U rack mountable chassis 3U rack mountable chassis 3U rack mountable chassis

24GB RAM 16GB RAM 32GB RAM 64GB RAM

2 PCI-E Slots 2 PCI-E Slots 4 PCI-E Slots 4 PCI-E Slots

2 Built-in Ethernet Ports 2 Built-in Ethernet Ports 2 Built-in Ethernet Ports 2 Built-in Ethernet Ports

6TB Storage 4/8/16TB Storage 16/32TB Storage 32/48/64TB Storage Optional OmniStorage: 32/48/64TB Up to 128TB total Storage

OmniAdapter 1G and 10G OmniAdapter 1G/10G MX OmniAdapter 1G/10G MX OmniAdapter 1G/10G/40G

6.5Gbps CTD 3.8Gbps CTD 8.8Gbps CTD 20Gbps CTD with OmniStorage


WatchPoint Centralized Monitoring for Distributed Enterprise Networks

• High-level, aggregated view of all network segments

– Monitor per campus, per region, per country

• Wide range of network data

– NetFlow, sFlow, OmniFlow • Web-based, customizable

network dashboards • Flexible detailed reports • Direct link to detailed,

packet-based analysis


Comprehensive Support and Services Standard Support Maintenance and upgrades Telephone and email contacts Knowledgebase MyPeek Portal

Premier Support 24 x 7 x 365 Dedicated escalation manager 2 customer contacts per site Plug-in reconfiguration assistance

WildPackets Training Academy Public, web-based, and on-site classes Complete curriculum: technology and product focused Practical applications and labs covering network analysis,

wireless, VoIP monitoring and advanced troubleshooting

Consulting and Custom Development Services Deployment, configuration, and assessment engagement Systems integration and testing Application integration, driver, decode, interface development


WildPackets Key Differentiators • Visual Expert intelligence with intuitive drill-down

– Let computer do the hard work, and return results, real-time – Packet /payload visualization is faster than packet-per-packet diagnostics – Experts and analytics can be memorized and automated

• Automated capture analytics – Filters, triggers, scripting, and advanced alarming system combine to provide

automated network problem detection 24x7 • Multiple issue network forensics

– Can be tracked by one or more people simultaneously – Real-time or post capture

• User-extensible platform – Plug-in architecture and SDK

• Aggregated network views and reporting – NetFlow, sFlow, and OmniFlow

Presenter

Presentation Notes

Expert intelligence… real-time… automate alarms and actions. Verbally give examples: Here is what we actually do. TOOT! More highly evolved analytics than any other product.


24x7 Network Monitoring, Analysis, and Troubleshooting

Presenter

Presentation Notes

Simply put, at WildPackets we’ve created an extensible, scalable network platform that illuminates every part of your network. We show you what’s happening on every network segment--wired or wireless, LAN and WAN, even Gigabit. We’re not just capturing packets; we’re providing real-time expert analysis that identifies problems such as unresponsive servers, poor application performance for end users, DoS attacks, and more. The analysis is performed locally everywhere you have a network. At headquarters. In remote offices. WatchPoint and The OmniPeek Product Family: • Provides real-time troubleshooting of mission-critical network services • Covers entire enterprise networks, including network segments at remote offices • Gives engineers powerful analysis relevant to today’s networks • Secures diagnostic communications so analysis never compromises security • Optimizes diagnostic communications to minimize impact on networks using Intelligent Data Transport™ • Is flexible, scalable, and extensible to grow with network needs • Monitors and troubleshoots Voice and Video over IP applications without having to invest in stand-alone troubleshooting tools or special hardware • Monitors and analyzes remote network segments • Analyzes application performance in the context of overall network activity


Thank You!

WildPackets, Inc. 1340 Treat Boulevard, Suite 500 Walnut Creek, CA 94597 (925) 937-3200

wireless network analysis 101 vofi (voice over wi-fi)

Documents

vofi analysis

wireless landscape

vofi voice

vofi jitter jitter

vofi voipvofi

vofi administration

vofi agenda

data network