Subject: [NEXTEL-1] Old Radio Technology Fades Away

From: Marcel <[email-masked]>
Date: Mon, 16 Jun 2003 17:29:23 -0400

Old Radio Technology Fades Away

06/16/2003

The recent and perhaps inevitable decision by wireless communications
firms such as AT&T Wireless and Verizon Wireless to cease supporting
cellular digital packet data (CDPD) networks as soon as mid-2004 is
causing ripples -- if not a tsunami -- throughout the transportation and
public safety communities, especially in larger metropolitan areas.
These communities were among the first users of CDPD for basic data
communications tasks, such as communication from dispatchers to mobile
display terminals (MDTs) in police cars, or communication between
traffic management centers and field devices like variable message signs
(VMS) or intersection controllers.

Clearly, newer and faster wireless data communications technologies that
are replacing CDPD will open the door to many new and more powerful ITS
and security applications, but the transition to these technologies is
causing significant challenges -- and angst -- to agencies whose current
systems are dependent on CDPD. To help understand how these communities
are dealing with what some have called the "demise" of CDPD technology,
the ICDN contacted public safety and/or transportation officials in New
York, Washington, DC, Utah, and Houston, TX, as well as a communications
technology expert who is watching and analyzing this transition closely.

Vanishing CDPD Services

AT&T Wireless and Verizon Wireless are the two largest purveyors of CDPD
services, and both have announced their timeframes for exiting that
market. In a wide-ranging announcement in October, 2002, AT&T announced
that it would stop selling CDPD services by March 31, 2003 and shut down
the network in June, 2004. (An AT&T representative had not returned the
ICDN's inquiry seeking additional details by press-time.)

Verizon Wireless, the other large CDPD provider, has been publicly less
specific about its plans regarding CDPD, but has informed its customers
privately that it ultimately plans to exit the CDPD marketplace. A
Verizon Wireless spokesperson that the ICDN contacted was quite specific
about the company's intentions. "We are planning to sunset the CDPD
network in December 2005," says Andrea Linskey, Executive Director for
Corporate Communications at Verizon Wireless.

Each firm is aggressively marketing its next-generation data
communication technology as a replacement for CDPD. In AT&T's case, that
technology is called Global Systems for Mobile communications (GSM) and
General Packet Radio Service (GPRS), and the company said in a press
release that it had completed a nationwide rollout of its CSM/GPRS
network in the third quarter of 2002. Verizon Wireless, by contrast,
announced the availability of its new technology, the "1XRTT Express
Network," for a number of major cities in the Spring of 2002, and that
network is now available "everywhere we service," according to Verizon
Wireless' Linskey. The 1XRTT technology was earlier called "CDMA2000"
(CDMA stands for Code Division Multiple Access.)

Much Higher Speeds (But How Much Higher?)

Both of these CDPD-replacement technologies offer the potential of much
higher communications speeds when compared to CDPD's almost glacial (by
today's standards) maximum speed of 19.2 Kbps. AT&T's GPRS network will
support peak network speeds of wireless data transmissions up to
115KB/sec, according to the company's literature. Customers on Verizon
Wireless' 1XRTT Express Network can expect minimum data transmission
speeds between 40 and 60 kilobits per second (Kbps) with bursts up to
144 Kbps, according to an April 2, 2002 press release.

In the hotly contested wireless marketplace, both firms have also
preannounced their next-generation wireless data communication
offerings:

Verizon Wireless will debut its new "1xEV-DO" network in Washington, DC
and San Diego, CA in the third quarter of 2003 that will support "secure
peak data transmission speeds of up to 2.4 Megabits per second,"
according to a company press release.
AT&T Wireless will deploy its next-generation "W-CDMA" wireless
technology, which it says reaches a peak network speed of approximately
two megabits per second, in "four major U.S. markets" by the end of
2004, according to a company press release.
Communications expert Carl Kain, a Principal Electrical Engineer from
Mitretek Systems, is studying the impact of the dropping of CDPD
services in conjunction with a larger three-phase project funded by the
U.S. DOT's ITS Joint Program Office (JPO) to assess the impact of
changing communications technologies to transit properties. "We're
actually targeting the transit folks, but the work is really relevant to
anybody who has a land-mobile radio system in the public safety channels
or uses CDPD or uses telemetry, because all of these services are being
impacted by various FCC (Federal Communications Commission) actions," he
says. "They're all in the same pickle," he adds.

Kain says that CDPD users today typically cannot come close to realizing
an effective data rate of 19.2 Kbps. "When you subtract the overhead
out, you're actually dealing with about 13 Kb per second, and that's
shared by every user who's concurrently accessing that particular
channel," he says, adding "Most users report actual throughput rates of
about 2 to 6 Kbps."

Kain says that users should not necessarily take the vendor's claims
about the speeds of their current or upcoming technologies at face
value, either. "The other data services should be faster, [but] a lot of
it depends on how the carrier has provisioned the service," he says.
"For GPRS, in rough and perhaps overly simplistic terms, there's the
equivalent of 8 voice slots per 200 kHz frequency channel. Since they
share data with voice, they have to decide how much voice capacity they
can sacrifice for data.

"In one of the services we've tested, we're getting the equivalent of
one voice channel on the uplink -- such as communication from a vehicle
to the base station -- and four voice channels on the downlink. For some
of the data rates we've seen, the uplink data rate isn't all that much
better than CDPD is, while the downlink is considerably better, like 30
Kbps or 40 Kbps. In some of the other services we're seeing uplink rates
closer to the 25-40Kbps range. It's a matter of whether it's CDMA-based
or GSM-based, and how the particular service provider has decided to
provision it. They're certainly capable of higher speeds [than CDPD],"
he says.

Opening Up New Applications

Clearly, the availability of faster wireless communications will be a
boon for data-intensive ITS and public safety applications, particularly
those involving the communication of significant amounts of data or even
video snapshots from field devices to a central control or dispatch
center, or a hospital. However, these new technologies are not
necessarily designed or optimized for such applications, because of the
aforementioned disparity between the uplink and downlink data rates.
Kain says that it's both typical and understandable that the uplink
speeds for the new CDPD-replacement technologies would be slower than
downlink speeds. "They're all asymmetric because they assume all the
users are going to be Internet users, they're going to
click-and-download and click-and-download," he says.

For its project for USDOT, Mitretek Systems built a small transit
application than enables video from a security camera on a bus to be
sent back to a control or dispatch center in near real-time. Kain says
that in early proof-of-concept testing he was seeing a video
transmission rate of from 1 to 15 frames per second, a significant
improvement over the several-frames-per-minute rate that transit
agencies, including Capitol Metro in Austin, TX, have reported from
similar CDPD-based applications. "It's a big difference," he concludes.
A report on the results of this evaluation, comprising "Phase 2" of the
USDOT-sponsored project, is due out in July 2003.

How to Get There from Here

The promise of these new wireless datacom services notwithstanding, the
issue of both maintaining service on today's CDPD-based applications
while transitioning to next-generation wireless services remains
front-and-center in the minds of staffers at many agencies. To get a
better handle on the scope of the challenge, the ICDN interviewed key
individuals from public safety and/or transportation officials from New
York, Washington, DC, Utah, and Houston, TX.

New York State Police: Serious Concerns about Spotty Coverage and
Security Problems

Captain Henry deVries, a Manager with the New York State Police on
assignment with New York State DOT (NYSDOT), says that the transition to
newer wireless technologies will be costly and that there are many
unanswered questions dealing with coverage and security concerns. He
says that his agency currently uses CDPD to transmit data from dispatch
centers to field units and to communicate with variable message signs.

deVries says that CDPD works well throughout New York State because of
the long-standing analog cellular roaming agreements in place between
competing firms, which means that users are assured of continuous CDPD
coverage no matter which carrier actually provides the service. That
situation will no longer exist with the CDPD-replacement systems, he
says. "The big communications vendors are phasing into newer, more
broadband wireless solutions. They're not going to work off each other's
systems anymore -- they're going in two separate directions," he
observes.

Because AT&T Wireless and Verizon Wireless are transitioning to
non-mutually-compatible systems, deVries is concerned that the ability
to consistently communicate with public safety vehicles could be
compromised in the future. "For instance, say you need to utilize
Carrier A's service along a corridor, and somewhere on that corridor
you're roaming onto Carrier B's network that [for CDPD] provides service
through a partnership with Carrier A. In the future Carrier B may no
longer provide that service because it doesn't provide the same
technology."

Verizon Wireless contends that coverage using their new wireless data
services is a non-issue. "The CDPD network is much, much smaller, even
with roaming partners, than the breadth of scope that they would receive
with the 1X CDMA network," says spokesperson Linskey. "They would never
be roaming off of Verizon in New York. Why roam when you have a
nationwide network that covers 233Mill POPS (population served), while
CDPD was deployed in a much more pocket-type type of fashion?" she asks
rhetorically.

deVries remains unconvinced, in part because he says that the wireless
providers have not kept their promise regarding CDPD service. "When we
set all this up, we were told that there was a five-year viability --
and this goes back to as recently as six months ago," he says. "Shortly
after buying the last batch of hardware and setting up our second frame
relay from a second vendor, we were told 'a year from now we'll be
shutting down our service, these are the things we're migrating to, and
this is what you'll need to do if you still want to stay our customer,'"
he recalls. "A lot of the questions that we've asked have still gone
unanswered," he adds.

deVries says that the changeover from CDPD to some as yet unidentified
new technologies could be very costly. "Whatever device you have that
utilizes CDPD, you'll need new equipment. The modems won't be the same,
and there'll need to be software upgrades. If you're connecting to the
service through frame relays, those will also need to be changed," he
observes.

He also says that the transition to CDPD-replacement technologies
involves serious security issues. "Right now we use static Internet
Protocol (IP) addresses. The computer knows 'my computer in my car is my
computer in my car' and talks to it. That changes with the new
technologies, and it really hasn't been clear how they'll ensure
security with dynamic IPs that change every time the computer signs onto
the system. There are some evolving and emerging technologies and
programs out there that will fix this [situation], but they may be
cost-prohibitive for public agencies and may not meet the level of
security we require."

Utah State Police: Transitioning from CDPD is an Opportunity

The Utah Highway Patrol is well aware of the sunsetting of CDPD
services, but has a very different "take" on that eventuality. "It seems
like there's a panic in law enforcement right at the minute, with
everyone wanting to know exactly where they're going," says Lt. Jim
Mathies, Section Commander for Technical Services at the Utah Highway
Patrol. "We're in no big hurry to move right at the minute -- we have a
lot of options right now," he says. "There are some new technologies
coming out with even faster speeds in the 3rd and 4th quarters of this
year. We're looking at some other options, as well. We have some 800 MHz
voice services and are looking at the possibility of piggybacking data
on that."

Mathies says that about two-thirds of the Utah state troopers have CDPD
coverage in their vehicles, but the remaining one-third are outside of
the current CDPD coverage areas. "We're trying to find a wireless
solution that will work for everybody," he says. AT&T Wireless is the
agency's only CDPD vendor, so it doesn't face any roaming issues similar
to those in New York State. Mathies says that CDPD replacement services
from the wireless vendors could be too costly. "Right now they're priced
more than what CDPD costs, and that is an issue for us, because I have
400 CDPD accounts right now and pay about $13 to $14 thousand per month
for these services. I just can't handle an increase in that cost right
now."

Mathies says that the state recently issued an RFP for a
CDPD-replacement wireless communication system that would "piggyback" on
the state's current infrastructure of voice communication towers. He
says that one vendor "can come in and do a 19.2 connection statewide
based off the towers we currently have with really good coverage, and
they say they're coming up with faster speeds. We're just hanging loose
and seeing what happens in the next little while before we make a move,"
he says.

Mathies says that he and his colleagues are already planning for higher
data communications speeds in the near future. "We've got all sorts of
new things going," he says. "We're about to start throwing images out to
the car. Certainly some faster speeds would help us with that." He says
that the Utah Highway Patrol uses a product called "Public Safety
Inquiry," or PSI, for email and chat applications and state/local
registration lookups over wireless connections. "We keep piggybacking
more things on that," he says. His agency is about to introduce silent
dispatching, and an informal group of public safety and transportation
officials in Utah is planning to support wireless multiple-agency
queries of a database that contains nearly 200,000 citations.

Mathies says that his agency is also deploying some new wireless
technologies now in anticipation of the cutoff of CPDP services. "We're
in the process of deploying some 802.11 hotspots around all of our
sections, district offices and drivers license offices, and we're trying
out some products that will do automatic switching between different
technologies such as CDPD and 802.11," he says. "That opens some
opportunities for us, as well. One of the enhancements we'll be doing to
our accident program is allow troupers to attach accident images to
[their reports]," he says, adding that other new products look
promising. "The software for one product is smart enough to know to move
the data up when it's on a 19.2 connection, but wait for a 10 or 11
megabit pipe to move the images up," he says.

CapWIN (Washington, DC area): Technology Independent (but will demo with
CDPD)

CapWIN (Capital Wireless Integrated Network), an ambitious effort to
used advanced technology to interconnect public safety and
transportation agencies from adjacent jurisdictions in the Washington,
D.C. area (see CapWIN Heads Toward Deployment), is currently using CDPD
from Verizon Wireless for pilot testing. The initiative will continue to
do so as the project begins beta testing in the next 45-60 days.

However, the ultimate CapWIN system is wireless technology neutral, says
Mike Hill, CapWIN's Director of Field Operations. "We're using CDPD in
our initial utilization of the communication switch. However, we're
building a technology that will accept any number of different types of
communication protocols," Hill says. "The subscribers to the system
would bring their own communications protocols to us, and the technology
we're using is fairly seamless as to what that protocol is. We're using
a commercial, off-the-shelf vendor's product that is built to accept
almost any known communication protocol on the market today," he says.

Hill acknowledges, however, that some of the public safety and
transportation departments that participate in CapWIN -- and
particularly larger agencies such as the state DOTs and highway patrols
in Maryland and Virginia -- could well have challenges with the
transition from CDPD to newer technologies. "When you're dealing with a
smaller agency that doesn't have as large a geographic area to cover,
normally you can find one provider in that whole area that can give you
the communication protocol that you're looking for," Hill says.

Hill adds that hardware is available today that can sense which type of
wireless protocol, such as CDPD and CDMA, is available, and then do what
he calls a "seamless transfer of that protocol." He acknowledges,
however, that the retrofitting of existing CDPD-only systems to
multiple-protocol systems would likely be "an expensive endeavor" and
that the customer would probably have to contract with each wireless
carrier separately for each separate protocol. "In today's economy, that
cost is going to be prohibitive in most cases where public safety or any
kind of government initiative are involved. However, there are devices
out there that you can throw into a vehicle that allow you to switch
from a private RF (radio frequency) network to a commercially wireless
service like CDPD or CDMA," he says.

While acknowledging the difficulties in transitioning from CDPD to other
technologies, Hill welcomes the capability that will come from faster
technologies. "CDPD is a strong limitation in our ability to enhance the
[CapWIN] system because of its narrow bandwidth capability. Although
CDPD going away creates some near-term hardships on subscribers, in the
long run it's not that bad of a proposition that it does go away." he
says. He suggests that the demise of CDPD might be an excellent
opportunity for public safety and transportation departments to present
a unified front to the wireless provider industry. "If we do come
together and speak as one, it gives us a little more power to negotiate
and to try to work out those issues with regard to public safety and
wireless access," he says.

Houston: May Need to "Switch 'Horses' (Wireless Technologies) in the
Middle of a Stream"

In Houston, TX, Houston Metro's $120 million Regional Computerized
Traffic Signal System (RCTSS) project is funding major traffic signal
control system changes for bus routes inside Houston's Beltway 8, an
area encompassing more than a 9-mile radius from downtown Houston. A
major objective of the RCTSS project is to improve about 1500 traffic
signals that belong to local agencies that partner with Metro, including
the transportation departments from the City of Houston, Harris County,
and several smaller local jurisdictions, as well as TxDOT's Houston
District. Once these signal system improvements are complete, they will
be turned over to these partner agencies that will be responsible for
ongoing operations and management.

"One of the scope requirements that RCTSS must satisfy is that each
intersection needs to be able to communicate back to a central console
located in Houston TranStar, the transportation and emergency management
center here in Houston," says Loyd Smith, Director of Traffic Management
for Metro. To enable that communication, Smith says that approximately
700 of those traffic signals "will be served by a wireless transmission
medium of some kind."

"In the course of developing this program over several years,
communications design and costing and implementation strategies have
been a particularly complicated feature of the activities," Smith
acknowledges, quickly adding "That is not at all atypical for projects
of this type." He says that two years ago Metro's consultants prepared a
communications master plan for the RCTSS project. "The recommendation
that evolved and was reviewed with our partner agencies as it developed
had, in our case, a packet-based, carrier supplied transmission as the
preferred method, and CDPD here locally was the service that rose to the
top," he recalls.

Once the decision was made to deploy a CDPD-based wireless communication
capability between TranStar and individual traffic signal control
cabinets, the RCTSS team began working on a field trial that would
confirm the feasibility of the CDPD approach. "The impact [of the CDPD
choice] was that we had to take the time and expense to modify the
traffic signal application software that we're using so that this
different type of data communication could be accommodated," Smith says.
He says that the traffic signal control software had to be modified for
what he calls "packet-based transmission" rather than the normal
"circuit-based transmission." Approximately 80 traffic signals in the
areas of the Texas Medical Center and University of Houston were
involved in that field trial, which ended successfully in the spring of
2002 and concluded that the CDPD approach was, indeed, feasible.

Houston Metro then moved into negotiations with the local CDPD carrier,
Verizon Wireless, and executed a contract with Verizon to support nearly
700 signal sites, Smith says. He says that in the contract negotiations
Verizon Wireless made it clear that the company ultimately planned to
exit the CDPD business, although the details of this exit were somewhat
sketchy. "Through the course of our negotiations [Verizon Wireless]
indicated that they had some concerns about a guarantee or clause within
the contract that would specify that they must maintain the CDPD service
to us as a customer for a defined period," he says. "The key point of it
is that we had requested a longer period and they came back in
negotiations and said that they wished for there to be a shorter period.
They were up-front and honest about it, although not wishing to be
overly specific," he says.

Smith says that the final ratified contract with Verizon Wireless says
that the carrier can discontinue service as of December 2005, the same
date provided to the ICDN by Verizon Spokesperson Linskey. He says that
within the last few months the Metro Board awarded a contract to install
the associated antennas and modems, and is currently negotiating some of
those work authorizations.

Smith says that the RCTSS team realizes that the communications master
plan ultimately needs to be what he calls a "living document," and that
his staff was aware of the news stories that began to emerge in the
fourth quarter of 2002 that both AT&T Wireless and Verizon Wireless were
moving away from CDPD service. "We certainly took note of those, as did
our partners," he says. "We did some reevaluation, which continues and
will continue as we go along."

"Here's where we found ourselves," Smith recounts. "Up until the news
stories of late last year and the more intensive reevaluation of where
the marketplace was headed, our plan was a real simple one. We had
selected CDPD. We were planning to install it at 700 locations. We were
going to go out on the street to bid 700 modems and 700 antennas, get
them installed, and sign up with Verizon as a customer. When the
marketplace uncertainty came up, what evolved was instead a more
cautious strategy. That strategy will involve roughly half of the 700
locations going forward this summer with CDPD. We will wait until we
update our master plan as it relates to wireless before we issue the
second half of the wireless installations, on the chance that the
crystal ball will become more clear that an alternative is feasible,
cost-effective, and available," he says.

In the meantime, he says, Metro is working to mitigate the impace of the
likely sunsetting of CDPD technology. The agency looked at what could be
done so that new hardware installed in the field could be compatible
with other types of wireless data communications systems. Smith says
that Metro decided to install dual-mode antennas that might work for
both CDPD and other technologies, such as CDMA. Unfortunately, Smith
says, currently available wireless modems are technology specific. "As
of right now, to my knowledge there are no modems that serve dual modes,
unlike cell phones where you can get one that talks in a couple
flavors," he says.

Smith adds that Metro has talked with vendors offering business
arrangements whereby Metro could pre-purchase the software changes that
would be required to the communications hardware should CDPD go away
some time in the future. "As a business decision we chose not to get
ourselves tied in there, essentially deferring [the cost of] any
hardware changes that might come up," he says.

Smith says that Metro may, in fact, choose to implement an alternative
to CDPD for the remaining 350 or so wireless intersections, using such
technology as Verizon's 1XRTT (CDMA2000) offering in the near future.
However, he sees two problems with moving to one of the newer data
communications technologies:

The availability of field-hardened hardware. "To my knowledge, the
alternative next-generation, carrier-based equipment marketplace has not
caught up with the airtime offerings," he observes. "In other words, I
can go out to Verizon today and get a card for my laptop that uses the
next-generation [technology] that is expected to replace CDPD. They
offer that as a service today. That is not true when your needs are for
a hardened, heat-tolerant unit that goes out in a traffic signal
cabinet."
High cost. Smith says that the difference between the list price of CDPD
versus 1XRTT services for unlimited transmission volume is "nearly a
difference of 1 to 2," which he says could translate into a difference
from approximately $40 to $50 per intersection using CDPD versus $80 per
intersection using 1XRTT.
Smith acknowledges that the higher transmission rates afforded by
CDPD-replacement technologies could provide real benefits, but the cost
issue will likely take center stage. "We had to simplify the
transmissions from the intersections to TranStar [using CDPD]," he says.
"For example, the real-time transmission of loop detection data from the
intersection to central can eat up some bandwidth. When you're talking
about fiber optics that bandwidth is no big deal. However, when you're
trying to stay within a practical bandwidth of perhaps 10K bits per
second you pay much closer attention to it," he says, adding "So we
chose not to bring real-time loop data from each intersection across
CDPD." Smith says that a higher speed wireless connection would likely
support real-time data communication, but that "in my personal judgement
it's not worth $40 a month extra just to be able to see the detection
lights on your screen at TranStar go forward."

Transit Issues

The impact of CDPD's demise goes beyond police and traffic management
applications. Mitretek's Kain says that the sunsetting of CDPD service
could also have a direct impact on transit agencies that utilize the
wireless technology for fare payment, automatic vehicle location (AVL),
route downloading for paratransit systems, or so-called "next bus"
applications. "The problem I've seen, particularly with the transit
folks, is that when they buy something that uses a wireless data
service, the modem is generally imbedded into the device, and it's very
difficult if not impossible to get to," he says. He cites the example of
a fare box that uses an imbedded CDPD modem. "If CDPD goes away, that
change could put your fare box out of business," he says. His advice:
"When you use a wireless service, start thinking in terms of a device
that can incorporate a quick upgrade."

Planning for Technology Change (and Obsolescence)

Clearly, the rapid evolution of wireless communications technologies
will inevitably change the way many public-sector users plan for and
implement these technologies. "I'd hate to change and then change again
after a while," says Lt. Mathies of the Utah Highway Patrol.
Unfortunately, the current rapid change in the landscape of wireless
data communications technologies shows no signs of abating, so agencies
will likely need to consider technology change (and obsolescence) in
their communications plans from now into the foreseeable future.

"In the normal scheme of things, public sector agencies are accustomed
to buying things that last 10 years," says Mitretek's Kain. "Some of the
data services that we're seeing are significant improvements over what
we had before, but a lot of them are interim steps to the carrier's 3G
(third generation) plan. Some of these technologies may not be around
very long. CDPD was around for about 5 years.

"In our area we've had a new CDMA2000 offering from Sprint and 1XRTT
offering from Verizon within the last year, and now we're seeing the
introduction of another service (Verizon Wireless' 1xEV-DO) that's the
next phase," he observes. "If the EV-DO thing from Verizon turns out to
be very successful, they'll start phasing out the 1XRTT service in favor
of the EV-DO service because most of their subscribers are people using
laptops and PDAs (personal digital assistants) on the Internet. It's a
mindset where people usually upgrade their phones in 18 months," he
says. "The mindset of the bulk of their customers is 'the new service is
5 times better than the old service? Fine, for $150 I'll buy a new modem
and toss the old one.'"

Verizon Wireless' Linskey seems to agree that each generation of
wireless technology could have a limited lifetime, without specifically
addressing any particular product or technology. "Every technology
becomes outdated and it becomes less of an issue of carriers not wanting
to support a technology and more about what's the available
infrastructure and what kind of upgrades [the carrier] can do to the
existing system," she says.

------------------------ Yahoo! Groups Sponsor ---------------------~-->
Get A Free Psychic Reading! Your Online Answer To Life's Important Questions.
http://us.click.yahoo.com/Lj3uPC/Me7FAA/ySSFAA/61FxlB/TM
---------------------------------------------------------------------~->

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/