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The Reality of FMC

Joe EpsteinMeru Networks

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

What is FMC?• One phone, One number, Multiple Networks

– Wi-Fi and Cellular together

– But is it really worth it?– Is it easy to deploy?

Caller

Mobile Phone

• Strikingly simple concept– Does it work?

Wi-FiCellular

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

The Power of FMC• Reachability

– Users can be reached anywhere• Indoors or outdoors

• In the office or on the road

• Productivity– No worries about flight delays, travel delays, missed connections– Enhances Workforce Mobility

• Address-free mobility

• Work from any office—goes with you.

• Cost savings– Reduced initial costs

• One device per person: no need for desk phone or wiring

– Reduced operating costs• Office indoor calls are free (or reduced)

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

The Choices…• You have to choose

– Who owns the phone number?• The cellular carrier or• You

– Do you care about seamless handoff?• Or is everywhere reachability enough by itself?

– Do you want to bring in new vendors just for FMC?

• Your choice picks– The technology– The features– Whether you’re locked in to a solution

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Case Study: An FMC Winner• Osaka Gas

– Japan’s second largest utility company– Completely unwired office

• 11,000 office desk phones reduced to 4,000 conference room phones, hall phones, and backups

• 4,000 existing wireless extensions converted to FMC

– Address-free hotelling environment– Estimated savings per year

$4 million

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Carrier-based FMC• The carrier owns the number

• The technology– Today, UMA– The carrier sees the enterprise as

nothing more than a big hot-spot

Caller

EnterpriseWi-Fi

Cellular

Carrier’s Network

Internet

Wi-FiHotspot

EnterpriseBorder

(650) xxx-xxxx

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Carrier-based FMC (2)• IP becomes an extension of the carrier

– Cellular signaling and voice packets get wrapped in UMA tunnel

– These opaque packets get tunneled through the enterprise, to the phone

• Why might carriers like this model?– Works across any IP-based network– Easier for them to deploy– Enables carrier to charge for every call – Easy to abstract out the part that’s the most variable

• The enterprise

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Features of Carrier-based FMC• True one-phone number system• But number is outside the enterprise

– Uses a typical cell number– Abbreviated (5 digit) dialing available only if software is configured

to fill in the missing digits– No integration with enterprise call systems– All calls are still outside of the enterprise, coming in—even office to

office

• Complexity is partially taken care of by the carrier or handset manufacturer

– UMA phones already exist—no special software needed

– Presumably no tuning needed• Not true in practice

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Other side of Carrier-based FMC• Really designed for the home market first

– Coverage extension for out-of-range consumers first– Possibly will lighten load on carrier’s networks

• Limitations– Requires the enterprise to open a hole in the firewall for UMA– Questions arise about enterprise and guest user segregation– Strongly decreased visibility into the health of the network– Intra-office calls must go through carrier’s network

• Same as a normal carrier voice call

– Reduced cost savings: carriers may still charge for every call

• Extremely Limited Availability– UMA is available on some phone models today– One US carrier is in small trials, for the home market– Other carriers are looking past UMA to IMS

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Enterprise-based FMC• The enterprise owns the number

• The technology– Handset software + Enhanced PBX or added FMC Gateway– The enterprise sees the carrier as nothing

but an external phone line

Caller

EnterpriseWi-Fi

Cellular

Carrier’s Network

EnterpriseIP PBX

(650) xxx-xxxx(408) 555-xxxx

FMC Gateway

FMC Software

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Calling (650) xxx-xxxx

Enterprise-based FMC (2)• Hairpinning

– Phone roams outside of Wi-Fi network– The FMC Gateway registers on behalf of the phone to the PBX– The FMC Gateway creates new outbound call to the phone’s real

number and bridges the calls

Caller

EnterpriseWi-Fi

Cellular

Carrier’s Network

EnterpriseIP PBX

FMC Gateway

Calling (408) 555-xxxx

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Enterprise-based FMC (3)• FMC software on handset

– Adds another, new phone application to the handset

• Integrates with address book, to varying degrees• User must remember to use this application, and not the phone

application that comes with the handset

– Connects to FMC Gateway either through the WLAN or Internet

– Provides PBX access when roaming– Provides 5-digit dialing– Controls the Wi-Fi (SIP) and cellular endpoints in the

phone– Performs the seamless handover

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Advantages of Enterprise-based FMC• Enterprise owns the phone number

– Phone becomes a PBX extension, inside and out– PBX features are usually available

• Reduced cost calling– All internal calls run over the wireless LAN, when phone

is in the office– All external calls run over the PSTN, which is generally

cheaper than cellular

• Abstracts out the carrier– The largest unknown in the system, from an enterprise

point of view– Possibly easier to switch carriers

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Who Provides Enterprise-based FMC• PBX + Handset Partnerships

– Example• Avaya/Nokia, with Avaya’s one-X software preloaded on phone• Works with Avaya IP PBX

– Full PBX integration– Higher degree of phone integration– Limited to the PBX and phone vendor

• Startups and independent companies– Requires FMC Gateway independent of PBX

• FMC Gateway may use PBX APIs• Or may be fully independent and use SIP

– Also requires custom phone software• Varying degrees of integration with the phone

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMCThe Other Side of Enterprise-based

FMC• Occupies more enterprise telephony resources

– Incoming calls to roaming phones must take up two lines and two ports on the PBX

– Outgoing calls from roaming phones may also share this problem

• Many solutions are early– A number of them are in prototypes or beta– Many are not widely deployed– Technical issues may restrict to a subset of the already

small set of dual-mode phones

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

The Critical Pieces

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Voice over Wi-Fi• This is the biggest variable in all types of FMC

• Forces enterprises to become “carriers” to their employees

– Must provide toll-quality voice service levels to phones• Requires “SLA” thinking

– Must monitor for outages or poor quality– In general, requires a much higher degree of

sophistication about the wireless network

• Without strong Voice over Wi-Fi service, the system collapses back into cellular-only

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Why Strong Coverage is Crucial• The handset has to choose which network to pick

– Which one is currently better: Wi-Fi, or cellular?

• Each change is expensive– If no seamless handoff is supported, then the call is dropped– Seamless handoff may still have seams—sometimes around 2

seconds– Using cellular when the phone is indoors costs money

• Handsets choose Wi-Fi when they can associate with high signal strength

– Low signal strength or packet loss can signal to the handset to switch back to cellular, even when no call is in place

• Even small coverage holes within the enterprise can, thus, trigger handover

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Why Wi-Fi Handoffs Hurt• Well-designed deployments have coverage everywhere

– Usually one access point provides good signal at every location

• However, phones have to change channels during Wi-Fi to Wi-Fi handoff

– 3 channels on 11bg– 20 channels on 11a

• Phones have to scan– Phones stop transmitting, change channels briefly, and check for a

new access point– This either disrupts the call or takes a very long time to complete

• Handoffs may fail– Long delays in handoff may cause the phone to lose its old AP– This loss may trigger the phone to roam to cellular

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

How Voice Quality is Measured• Mean Opinion Score (MOS)

– Goes from 1 to 5– Originally measured by human

surveys

• R-Value– 100-point scale– Maps directly to MOS and back

• E-Model– ITU G.107 model for predicting voice quality based measurable factors– Fit into packet-based systems to provide quality on the basis of jitter, delay,

and loss

• PESQ– ITU P.862 method for measuring voice quality based on real samples– Better for measuring analog systems and the behavior

of new codecs

–4.0 – 5.0: Toll quality–3.5 – 4.0: Usable but dissatisfying, cellular quality or worse–3.0 – 3.5: Nearly unusable–1.0 – 3.0: Not recognizable

–80 – 100: Toll quality–70 – 80: Usable but dissatisfying, cellular quality or worse–60 – 70: Nearly unusable– 0 – 60: Not recognizable

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Why Toll-Quality Voice is Crucial• Several factors to poor voice quality

– Not just poor coverage– Density, Resource Starvation, Contention, Interference

• Handsets can’t detect these parameters well– Usually need to have an active call ongoing on Wi-Fi to

measure these

• Thus, handsets may end up sticking to a bad Wi-Fi network

• Users complain loudly– The system doesn’t work

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Why Data is Crucial• Except in rare circumstances, most Wi-Fi

networks are data networks– It may be hard to justify a voice-only network

• Even if data density is low, voice and data must not interfere with each other

– On some systems, data will degrade voice, especially when voice is at scale

– On other systems, voice will severely degrade data

• WMM, by itself, is not enough– Quality-of-service must recognize voice calls

specifically

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

What to Look For in Wi-Fi• Toll-quality voice, Always• Admission control, when resources are

overtaxed– Caller must get busy tone

• Strong coverage with no Wi-Fi handoff glitches– Stacked single-channel deployments eliminate scanning

and handoff

• High density support for voice– Phone users tend to congregate

• Voice and data must not interfere– Assured levels of quality of service, not just

differentiation of packet types

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Predictions & Hopes• UMA will fade out of consideration for

enterprises

• Handset and OS manufacturers may take over FMC phone software

– Expect to see APIs – An interoperability industry may or should form

• Technologies, such as 802.11u/802.21, may influence this

• Both PBX and independent models will remain– Different enterprise users will favor

different models

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September 10-12, 2007 • Los Angeles Convention Center • Los Angeles, California

www.ITEXPO.com

The Reality of FMC

Conclusions• FMC is Reality, outside of USA

– Slow adoption in the US– FMC is coming to USA, look for more deployments in 08– Exists everywhere else, outside of US

• The technology exists– Handset choices may be limited for a while here,

compared to overseas– Seamless handoff is still difficult– But mobility is available and solid

• The models are still in flux– Natural tension between carrier and enterprise-based

models