There's a war brewing around wireless broadband trials using TV white space in India
I think this whole issue of TV White Space is being clouded with needless convoluted semantics . The author also does not do much to ' clear the air '.Some basic facts have to be placed on the table and understood clearly.
1. TV White Space ( TVWS )is not an access technology. Hence the comparison with 3G/4G/cellular technologies is infructuous.
2. TV White Space is and is being positioned as a " Middle Mile " or a " Mobile Backhaul " technology. This means that it is supposed to compete/susbtitute with fiber or microwave. Indirectly, it is in direct competition to the Optical Fiber which is required to be laid between the Block and the Gram Panchayat ( GP )as a part of the NOFN/Bharat Net Project !
3. Going by the Expert Committee Report on NOFN, BBNL shall lay fiber at only 80% of the locations as it is not feasible to do so in the balance 20% locations. They have advocated the mixed use of UBR Backhaul technology (which works in the unlicensed bands ) and satellite technology for the technically non-feasible areas !
4. So , if at all there is a use case in the revamped NOFN project ( now called Bharat Net ) for such 'special technologies ' like TVWS, it is only in these 20% GPs only ( unless of course Govt. decides to abandon the fiber project and decide to opt for alternate long-distance wireless backhaul technologies ).
5. TVWS is being touted as a " technology for providing Rural broadband ". However before we join the bandwagon, it may be good to step back and find out what are we talking about . The moot question is that is this truly a broadband technology ? What are the bandwidths that TVWS is capable of providing ? . In the classical NOFN architecture, each GP was to be equipped with 100Mbps bandwidth which was meant to be used by different Telcos/Internet Service Providers/Cable TV providers etc to provide broadband enabled services to the 640,000 ( and not 500,000 ! ) villages . The early results of the trials with TVWS technologies have indicated a throughput of ~10Mbps against a spectrum requirement of 10Mhz ( under ideal conditions ). By simple extrapolation, this means that to provide 100Mbps, it would need a minimum of 100Mhz spectrum ! Surely, this cannot be a very efficient way of using the spectrum , when the entire " White Space " available is of that order only ( Refer IIT Mumbai study report ). Also, it is quite clear that in GPs which have higher bandwidth requirements due to presence of co-located schools, hospitals , government offices etc , TVWS technology may not be appropriate for such higher bandwidth requirements.
6. Digital India ensures provision of guaranteed broadband transmission bandwidths everywhere with guaranteed SLAs and not on ' best effort ' basis. We have yet to come across a single commercial network being run on TVWS technology anywhere in the world offering highly reliable ( five 9s grade ) and assured quality of broadband service.
7. It may be prudent to point out that ' field proven' High Capacity Wireless backhaul technologies do exist ( which provide scalable capacities of upto 1-2Gbps ) at distances of upto 10-13 kms , which are in licensed spectrum bands. These are extremely low cost, highly efficient, interference free, Point to Point links which can meet the requirements and complement the government's fibre roll-out in a more cost effective manner than ' special technologies ' viz. TVWS , treated in a special manner !
8. Besides, the issue of auction vs free/unlicensed spectrum remains as another moot point where the business case of TVWS hinges on keeping it unlicensed and thereby leading to frittering away of ' precious ' natural resource viz. spectrum , in contravention to the SC guidelines. Given the hype and buzz , it may suffice to state that TVWS has not yet passed the peak of inflated expectations ! I think it would be prudent for the government to let the dust settle down, before making the next move ahead.
November 05, 2015
The author responDS
Comments 1-5: A “comparison that is
infructuous”: The article asks: “Should TVWS be used only for 3G & 4G?” The
implied question: “or for other technologies including TVWS-specific ones?” The
article also states: “…the objective for Digital India is to use this
technology [TVWS technology, as against the spectral medium] in combination
with others…” Yes, the term “TVWS” is applied to both the medium – the spectrum
– and TVWS technologies, for the (new) technologies developed for that medium,
namely, 802.22 and 802.11af.
The commentator must surely know this, as also the
TRAI’s recommendations on the next comment:
“…direct competition to the Optical
Fiber”:
This perhaps reflects genuine confusion and/or lack of awareness of the
complementary role of wireless backhaul (including TVWS). The article clearly
mentions supplementing the backbone where laying fibre is too expensive or
infeasible. The TRAI’s recommendations on microwave for backhaul discuss this
in detail (see: http://www.trai.gov.in/WriteReadData/Recommendation/Documents/MW%20Reco%20Final29082014.pdf
UPDATED: January 18, 2020:
https://main.trai.gov.in/sites/default/files/MW%20Reco%20Final29082014.pdf
“Recommendations on Allocation and Pricing of Microwave Access (MWA) and
Microwave Backbone (MWB) RF carriers”, Telecom Regulatory Authority of India,
August 29, 2014,
AND
https://main.trai.gov.in/sites/default/files/Response%20to%20back%20reference%20on%20Microwave_17.11.2015.pdf
"Recommendations
On
Allocation and Pricing of Microwave Access (MWA)
and Microwave Backbone (MWB) RF Carriers
(Response to reference received from Department of
Telecommunications on recommendations of
16th October 2015"), Telecom Regulatory Authority of India, November 17, 2015).
The more fibre, the better. The question is to what extent it
can be deployed cost-effectively. For the rest, other technologies and mediums are
needed for the intermediate mile.
“By simple extrapolation, this means that to
provide 100Mbps, it would need a minimum of 100Mhz spectrum ! Surely, this
cannot be a very efficient way of using the spectrum , when the entire "
White Space " available is of that order only…”
Comments like this appear
to be misleading, especially when made by a commentator who seems to understand
the technological implications: if there are more cost-effective ways, those
are the ones to use. If not, use less perfect methods, including TVWS. The
objective is connectivity at reasonable cost, not designing or deploying the
most appropriate technology. Why should TVWS be used in any other way than to
provide a 100Mbps link to a node to which it is infeasible for cost or other reasons
to lay a fibre connection? What could be more desirable in the public interest?
Surely not the optimization of some academic measure of TVWS usage. This is
where the best is the enemy of the good.
Comments 6-8
"6. …We have yet to come across a
single commercial network being run on TVWS technology anywhere in the world
offering highly reliable ( five 9s grade ) and assured quality of broadband
service."
Response
In the author’s surmise, this may be because the pioneers of TVWS-use
and technologies (devices), namely, the USA, the UK, Singapore, already have
good fibre and cable networks over most of their geographies. It is only on the
fringes that they lack adequate connectivity. These are insufficient markets to
provide the level of demand that could have otherwise led to proliferation, and
therefore lower-cost devices and success. For instance, device makers are
relatively small companies. So it’s a chicken-or-egg situation. The markets
that are large enough are China and India, and both have started considering
TVWS. Huawei has even acquired one of the early manufacturers, Neul, which was
involved in the UK trials. The latter may be an indicator of possibly higher
volume production and deployment, assuming Huawei knows what it’s doing (and it
certainly seems to).
"7. It may be prudent to point out that ' field proven'
High Capacity Wireless backhaul technologies do exist ( which provide scalable
capacities of upto 1-2Gbps ) at distances of upto 10-13 kms , which are in
licensed spectrum bands. These are extremely low cost, highly efficient,
interference free, Point to Point links which can meet the requirements and
complement the government's fibre roll-out in a more cost effective manner than
' special technologies ' viz. TVWS , treated in a special manner !"
Response
This is
partly true, but leaves out the rest of the relevant facts; else, if they were
really low-cost (and unrestricted), such links would have been deployed
extensively in India. Instead, the high cost (and restrictive regulations) make
it impractical. This has resulted in the matter being taken to the Supreme
Court [Supreme Court civil appeal No. D29714 of 2010]. All this is given in
detail in the TRAI recommendations referred to above.
"8. Besides, the issue of
auction vs free/unlicensed spectrum remains as another moot point where the
business case of TVWS hinges on keeping it unlicensed and thereby leading to
frittering away of ' precious ' natural resource viz. spectrum , in
contravention to the SC guidelines."
Response
Consider this: the objective is digital
connectivity, in the sense of ubiquitous affordable access. It has not been
achieved, and appears infeasible without lower cost access across rural India.
If there are better, less expensive ways of providing it, suggest them by all
means. If you can’t, think about (a) the objective (ubiquitous affordable
access) and (b) constructive alternatives, and try to suggest practical
solutions, and avoid misleading or ill-informed comments. As for the Supreme Court guidelines, if the government formulates sound policies in the public interest, the court's aims will be well served.
9. "Given the hype and
buzz , it may suffice to state that TVWS has not yet passed the peak of inflated
expectations ! I think it would be prudent for the government to let the dust
settle down, before making the next move ahead."
Response
TVWS use with TVWS devices is
not proven. That’s what the trials (mentioned in the article) are about.
November 10, 2015
