Verizon's Backhaul Speed Race

Verizon Wireless said at the recent CTIA show that it aims to get 100-Mbit/s links to its cell sites as it moves to Long-Term Evolution (LTE), matching the current maximum speeds offered by the proto-4G base stations but not the some of the prototypes that vendors are already showing off at tradeshows and other events.

Backhaul -- the part of the network that links the radio elements to the wired Internet -- is the largest and most often overlooked gating factor for mobile broadband services. "You can’t simply have very fast links on the airlink side and really have it constrained on the backhaul side," Brian Higgins, executive director of the Verizon Wireless LTE Innovation Center, told LR Mobile in Vegas. (See CTIA 2010: Verizon LTE Gets Friendly.)

Verizon is trying to head off any backhaul issues upfront with fiber and -- occasionally -- microwave links to its LTE cellsites. As we have seen with AT&T Inc. (NYSE: T)'s iPhone 3G issues, having inadequate backhaul in place can result in bad publicity from big-ticket users. (See AT&T to Spend $2B More on Wireless in 2010 and AT&T Mobile Boss: NYC & San Fran Are 'Underperforming'.) "The view right now is that we're targeting to get 100-Mbit/s connections to each individual cell site," Higgins said of Verizon's backhaul plan. Click on the video for more:

Many US cellular networks use T1 lines, which provide 1.5 Mbit/s and can be bonded together for better performance. As we've already seen, this old, copper-based technology sometimes can't keep pace with 3G data demands, let alone a network that Verizon is hoping will get 5- to 12-Mbit/s downloads on average. Higgins claims that LTE performance will represent "a 10x increase over 3G."

The backhaul speed race, however, likely won't end there for Verizon or other carriers deploying proto-4G services. Infrastructure vendors, looking to capitalize on fast-growing demand for data services, are pushing LTE beyond its originally planned maximum speed of 100 Mbit/s downlinks from a base station.

NTT DoCoMo Inc. (NYSE: DCM) was already showing off 250-Mbit/s links on LTE in 2008. Huawei Technologies Co. Ltd. claims to have a commercial basestation that will support 150 Mbit/s. The technology has been pushed beyond 300 Mbit/s in tests. (See DoCoMo Takes LTE to 250 Mbit/s and LTE Hits 300 Mbit/s.)

It is questionable what some of these speed increases will actually mean in the real world. The 100-Mbit/s link that Verizon is talking up certainly accounts for the top line of LTE infrastructure performance for now. There are other factors to take into consideration, however, such as how many base stations are located at a cell site and how RF conditions for a particular location might actually affect the end performance of the radio network itself.

Hence, the difference between the base station performance and the link speed users can expect from this faster -- but still shared -- medium.

— Dan Jones, Site Editor, Light Reading Mobile

bollocks187 12/5/2012 | 4:40:04 PM
re: Verizon's Backhaul Speed Race

I'm too sexy for my Hat.......


Seriously good interview - what is consisent is the Verizon Clone and spokesperson - way behind the times.

Anybody who new how network planning would place 100Mbps to an LTE. Get ride of the old TDM garbage.






paolo.franzoi 12/5/2012 | 4:40:03 PM
re: Verizon's Backhaul Speed Race


I think that is why I see the whole Bonded Copper thing as a phase in the wireless backhaul.

For 3G expansion, bonded copper might have a place.  The question is - other than AT&T fixing their blue map - how much bigger is 3G coverage going to be?

For LTE, there is no point in bonded copper.  There is only fiber and wireless as choices (where the US will be primarily fiber).  

About the only question is there a way to leverage U-Verse and FiOS construction to provide the connectivity to speed things up.  This might mean some CWDM usage of the fiber, but might be much lower cost/quicker to build in some areas.



furious_george 12/5/2012 | 4:40:03 PM
re: Verizon's Backhaul Speed Race


"For LTE, there is no point in bonded copper.  There is only fiber and wireless as choices (where the US will be primarily fiber)."

Any insight or pointer to a reference/analyst that is expressing your quoted view?  Please note that I'm not disagreeing, but just genuinely interested in an "on the record" opinion.



paolo.franzoi 12/5/2012 | 4:40:02 PM
re: Verizon's Backhaul Speed Race

Are you asking me whether bonded copper is a waste or fiber is more likely than wireless backhaul US?

I would point to any number of studies that show that backhaul in the US is well over 80% land based not wireless.  There are significant issues with placing wireless backhaul from a regulatory standpoint.

In terms of bonded copper, it is real easy to look at rate reach charts and see that it will be impossible to reach many cell sites with 100Mb/s.  So, copper is dead.  The cell site will not get more bandwidth than it would for 3g.  So, why bother doing 4g over bonded copper.  So, lets make sure that we can set that parameter for you.  100 Mb/s over 5 miles symmetric.  Call me when that is less than several binder groups worth of copper.

Bonded copper has a small market in small business access and some 2.5g and 3g cell site bandwidth upgrades.  But there are limits to the bandwidth that DSL can deliver per pair.  This gets worse with more pairs due to crosstalk issues.  None of this is new or not well known.



psenior 12/5/2012 | 4:39:58 PM
re: Verizon's Backhaul Speed Race

100Mbit/s is a lot of backhaul bandwidth for a 4G Base Station (whether it's WiMAX, LTE, LTE-A or whatever comes after that). Lots of people forget that without a lot more spectrum all of today's carriers are limited in what they can deliver (the only exception might be Sprint/CLEAR who have around 100 MHz that they can use for 4G).

A typical Rel 8 LTE cell will deliver 15-20 Mbit/s on average (forgot the bullshit peak numbers). if you only have 10 MHz FDD you are stuck at 15-20 Mbit/s per cell.

Sure when 4x4 MIMO becomes a reality (and LTE-A arrives) the numbers will approve (maybe double), but they will still be much lower than 100Mbit/s.

If you want Base Stations to deliver 100Mbit/s (real broadband) you need 4-5 times the amount of spectrum to deliver it with. There are no shortcuts.




paolo.franzoi 12/5/2012 | 4:39:56 PM
re: Verizon's Backhaul Speed Race


I guess my only comment is that many 3G sites require 10Mb/s today.  Don't forget that the backhaul number includes all the services going to that site - not just the 4G data.

What carriers are looking for (and Verizon has been very specific about this through an RFP process) is 100 Mb/s fiber connectivity to the cell site.  If you you at what AT&T is doing they are moving to integrated backhaul boxes (Tellabs and Cisco being the vendors) with the ability to upgrade these to 100 Mb/s.  

Bonded copper (or just separate interfaces) are basically limited.  Over a long distance, let's call it 2 Mb/s per pair.  If you put in 10Mb/s to cover the 4G connectivity and you already have 10 Mb/s - you are talking about 10 pairs to the site.

All of this becomes a lot to handle.  So, what people are asking for is 100 Mb/s because:

1 - It has to be more than 10 Mb/s

2 - Ethernet doesn't have a 40 Mb/s interface

I would expect these links to be undersubscribed in the beginning.  Perhaps even getting a Carrier Ethernet service of say 30 Mb/s over a 100 Mb/s infrastructure.



rightware 12/5/2012 | 4:39:04 PM
re: Verizon's Backhaul Speed Race

So let me get this straight. The 4G standards committee formally defines '4G' as providing minimum speeds as 100Mbps via wireless and 1Gbps via a wired connections ... yet Verizon believes that 100Mbps backhaul per cell tower is more than enough to service their subscriber's future needs.

How is a network provider to add wireless capacity to its towers (via a dozen or more of 5/10MHz channels) with only 100Mbps backhaul to support it? 

Perhaps in Fantasyland but nowhere else.


OldPOTS 12/5/2012 | 4:39:02 PM
re: Verizon's Backhaul Speed Race

Anyone for 40 Mbps????


paolo.franzoi 12/5/2012 | 4:39:01 PM
re: Verizon's Backhaul Speed Race


Verizon is asking for fiber connectivity to all their sites which is a problem unto itself.  So, it should be a straightforward upgrade to get to 1G.  However, if you believe you are going to get 100Mb/s over the air I have a bridge to sell you.



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