June 16th, 2011
One of the issues I still don’t fully understand is the proposed reliance on satellite for backhaul by LightSquared, the proposed new Long Term Evolution service provider in the United States that hopes to use frequencies originally allocated for satellite communications.
LightSquared hopes to use the spectrum to create a national wholesale Long Term Evolution network.
But the reliance on a space segment for backhaul strikes me as less than optimal, given the latency introduced by the lengthy space segment, and the processing that might be required to support real-time services such as gaming, videoconferencing, voice and some enterprise apps.
I am told there are new coding techniques that allow satellite networks to support voice communications where it would have been quite difficult in the past. But I’m not so sure those techniques are cheap enough to deploy in a consumer setting.
A study by The Rural Mobile and Broadband Alliance (RuMBA) USA points out latency differences between fixed-line and mobile or satellite broadband. “If you ping a typical wireless access point within a home or small office network you should see an average latency of about 2 ms,” says Stephen Cobb, a consultant who prepared the report. See
http://rumbausa.ning.com/.
“If you are on a cable or DSL connection to the Internet and ping a commercial website like www.bankofamerica.com, you will see latency of about 60 ms. Unfortunately, a satellite Internet connection is likely to have a latency of 600 ms or more when contacting the same
website,” says Cobb.
Latency is not an overwhelming issue for some operations, such as casual Web surfing or even pre-recorded video, if the buffer is big enough. But it strikes me that relying on satellite backhaul as possibly difficult, especially for real-time services.
Tags: backhaul, latency, lte, satellite
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June 15th, 2011
Assuming the cost of installing and operating a base station is constant regardless of the traffic it carries (and it largely is), the “cost per bit” varies as a function of network utilization. In other words, a lightly-loaded network will have a high cost per bit, while a heavily loaded network will have low costs per bit.
Figure 1. Cost per GB as a function of network utilization and peak-to-average traffic, assuming a cost per bit of $5/GB at 50% network utilization, for a 4:1 peak-to-average traffic. The three lines show the cost curve for a different cost per bit at three different peak-to-average traffic levels, as the network utilization increases moving to the right.
During the initial stage of a greenfield installation, the operator has to establish coverage and has few subscribers. Established mobile operators also have few subscribers on a new network as subscribers are still on older networks. As a result, the base stations are still underutilized and the cost per bit can be extremely high.
As the number of subscribers grows, the cost per bit drops. The answer to the question “what’s the cost per bit” of backhaul or any other network is properly “it depends.” A better question sometimes is “what is the cost per bit of one solution, compared to another solution, at equivalent loading?”
http://www.senzafiliconsulting.com/Blog/tabid/64/articleType/ArticleView/articleId/51/Is-cost-per-bit-a-reliable-metric-for-wireless-data.aspx
Tags: cost per bit, mobile backhaul
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June 14th, 2011
ADVA Optical Networking says it has retained its number one position in the Ethernet Access Device market for the fifth consecutive year.
Figures from Infonetics Research show that ADVA Optical Networking’s FSP 150 family, featuring Etherjack and Syncjack technology, accounted for 16 percent of worldwide EAD revenue in 2010.
The “Carrier Ethernet Equipment” report from Infonetics Research shows that worldwide EAD revenue reached $667 million in 2010, an increase of 19 percent from 2009.
Infonetics Research expects revenues to reach $1.5 billion by 2015 with a Compound Annual Growth Rate of 18 percent from 2010 to 2015.
This growth rate is significantly higher than the seven percent CAGR for the overall carrier Ethernet market.
“The demand for EADs continues to grow at a rapid pace and shows no signs of slowing,” said Stephan Rettenberger, vice president, marketing at ADVA Optical Networking. “This growth is driven by several key applications, including strong demand for mobile backhaul applications and business Ethernet services.”
“The growth in service provider investments in carrier Ethernet equipment continues to outpace that of other telecom equipment, with annual spending expected to reach $37.5 billion in 2015,” said Michael Howard, co-founder and principal analyst for carrier networks at Infonetics Research.
See http://www.noodls.com/view/0905A95CBEE912371FCDD400BAFDE80C7507B00E.
Tags: carrier ethernet
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