I'm not sure if the attempted theft of copper cable is more prevalent in the United Kingdom than it is in the United States, or if the U.K. news media pays more attention to the crime than does the news media in this country. Either way, I never go too long without hearing about such a theft, or attempted theft, somewhere in the U.K.
Not long ago we told you about the young man who was nearly electrocuted while trying to steal copper cable from an electrical substation. The permanently scarred culprit spoke remorsefully at his sentencing.
Now I hear about the enterprising 33-year-old from Glasgow who made it look like he was supposed to be working in manholes while he was trying to make off with some of BT's copper cable.
According to reporting by The Courier (which takes you to the heart of Tayside and Fife), Dean Monaghan put on reflective clothing, erected a worker's tent, and put up signs and cones around manhole covers in his attempt to "hide in plain sight" last fall.
The attempt failed. I won't steal the entire story from The Courier. Enter the heart of Tayside and Fife yourself. Read all about it here.
Wednesday, June 29, 2011
Wednesday, June 22, 2011
The perils of patch cords
In a blog post, CommScope's director of channel development and training James Donovan outlines the potential risks that users take on when they complete their cabling channels by adding "just any" patch cords to installed permanent links. According to Donovan, even checking a patch cord's jacket for a stamp of standard-compliance does not ensure a top-notch cabling channel. As he notes, "standards specify minimum requirements only, and do not cover all the coupling and reflection effects that may occur within or between components."
Add to that Fluke Networks' recent assertion that most patch cords are only tested for wiremap, regardless of what is inkjetted on the jacket, and the perilous patch cord becomes a system component that deserves closer attention than it gets, in the opinion of many.
Donovan describes some of the measures CommScope takes to ensure its patch cords perform at the highest possible levels, and also gives an earful of what users might be in for if they are laissez faire (or, dare I say it, cheap) when it comes to patch-cord selection. Among the possible outcomes is intermittent continuity, which Donovan describes as "a network manager's worst nightmare."
You can read Donovan's complete blog post here.
Add to that Fluke Networks' recent assertion that most patch cords are only tested for wiremap, regardless of what is inkjetted on the jacket, and the perilous patch cord becomes a system component that deserves closer attention than it gets, in the opinion of many.
Donovan describes some of the measures CommScope takes to ensure its patch cords perform at the highest possible levels, and also gives an earful of what users might be in for if they are laissez faire (or, dare I say it, cheap) when it comes to patch-cord selection. Among the possible outcomes is intermittent continuity, which Donovan describes as "a network manager's worst nightmare."
You can read Donovan's complete blog post here.
Friday, June 10, 2011
FOA president chronicles training trip through Africa
Jim Hayes, president of The Fiber Optic Association, posted on the FOA website a summary of his recent trip to three African countries during which he, other FOA personnel, and professionals based in Africa provided fiber-optic training.
The training sessions took place May 9 in Johannesburg, South Africa; May 17 in Nairobi, Kenya; and May 20 in Lusaka, Zambia. In his journal-style summary of the trip, Hayes noted, "As one of the fastest growing markets for telecommunications, Africa is planning the installation of more fiber-optic infrastructure and needs trained technicians to perform the design, installation and maintenance work necessary ... Our visits to South Africa, Kenya and Zambia gave us a view into the variations in developments in Africa, with SA being on a par with the U.S., Europe or the Asian rim countries, Kenya rapidly building infrastructure and Zambia in an earlier stage of development."
He noted that many submarine cables reach African shores, and the current need is to build infrastructure within the continent and distribute it for general use.
Rather than copy or paraphrase Hayes's writing, I'll encourage you to read it for yourself here on the FOA website. Doing so will also give you an opportunity to see all the photos from the FOA's trip to Africa as well as to find other items and resources on that site. The "report from Africa" is part of the FOA's June online newsletter, which also includes an article that asks if telecom is dead, information about the new FOA iPad app, news about Corning running out of fiber and more.
The training sessions took place May 9 in Johannesburg, South Africa; May 17 in Nairobi, Kenya; and May 20 in Lusaka, Zambia. In his journal-style summary of the trip, Hayes noted, "As one of the fastest growing markets for telecommunications, Africa is planning the installation of more fiber-optic infrastructure and needs trained technicians to perform the design, installation and maintenance work necessary ... Our visits to South Africa, Kenya and Zambia gave us a view into the variations in developments in Africa, with SA being on a par with the U.S., Europe or the Asian rim countries, Kenya rapidly building infrastructure and Zambia in an earlier stage of development."
He noted that many submarine cables reach African shores, and the current need is to build infrastructure within the continent and distribute it for general use.
Rather than copy or paraphrase Hayes's writing, I'll encourage you to read it for yourself here on the FOA website. Doing so will also give you an opportunity to see all the photos from the FOA's trip to Africa as well as to find other items and resources on that site. The "report from Africa" is part of the FOA's June online newsletter, which also includes an article that asks if telecom is dead, information about the new FOA iPad app, news about Corning running out of fiber and more.
Thursday, June 9, 2011
Wall calendar takes comic look at data centers
I'm a bit late on the draw with this one but there's still plenty of time to enjoy and get use out of the March 2011-March 2012 wall calendar available from Communications Supply Corporation.
The calendar includes comic-strip-style artistry from CSC sales rep Diane Alber and focuses on data center environments. CSC put quotes around the word "educational" when describing the calendar's running comic strip called Kip and Gary. To me that means it's more fun than learning. On the slightly-more-serious side, the calendar also includes products that can be used in data centers.
The calendar is free to anyone who signs up to receive it. You can do that here.
Disclaimer: I ordered my calendar from CSC immediately before writing this, so I have not yet received it and can't tell you firsthand how humorous the comics are. But I'm eager to find out.
The calendar includes comic-strip-style artistry from CSC sales rep Diane Alber and focuses on data center environments. CSC put quotes around the word "educational" when describing the calendar's running comic strip called Kip and Gary. To me that means it's more fun than learning. On the slightly-more-serious side, the calendar also includes products that can be used in data centers.
The calendar is free to anyone who signs up to receive it. You can do that here.
Disclaimer: I ordered my calendar from CSC immediately before writing this, so I have not yet received it and can't tell you firsthand how humorous the comics are. But I'm eager to find out.
Wednesday, June 8, 2011
Nearly-electrocuted copper-cable thief speaks remorsefully
Several UK-based news sources have reported on the fate of 22-year-old James Sorby, who was nearly electrocuted by 22,000 volts of electricity while trying to steal copper cable from an electrical substation.
One of those sources, The Daily Mail, ran a story that includes graphic photos of Sorby shortly after his ill-fated theft attempt. The story also includes an image of Sorby's scarred hands. You can see the story here, but please be aware that you may find the images disturbing.
In remorseful comments, Sorby told legal magistrates, "My message is, 'Don't do it.' Before I did this, it was just an idea and there was no danger to it. Everyone thinks it's so easy and they have no idea how stupid they're being. When you think of getting involved in something like this, you don't think of the danger."
Sorby's plight was in the news because he was due to be sentenced for his crime. The Yorkshire Evening Post reports his sentence was a 12-month supervision order.
One of those sources, The Daily Mail, ran a story that includes graphic photos of Sorby shortly after his ill-fated theft attempt. The story also includes an image of Sorby's scarred hands. You can see the story here, but please be aware that you may find the images disturbing.
In remorseful comments, Sorby told legal magistrates, "My message is, 'Don't do it.' Before I did this, it was just an idea and there was no danger to it. Everyone thinks it's so easy and they have no idea how stupid they're being. When you think of getting involved in something like this, you don't think of the danger."
Sorby's plight was in the news because he was due to be sentenced for his crime. The Yorkshire Evening Post reports his sentence was a 12-month supervision order.
Friday, June 3, 2011
Encircled flux: A practical view
by Eric Pearson, CFOS
I have been following the encircled flux (EF) standard from the sidelines. From this position I do not have the entire picture. With that understanding, I offer the following information.
Any measurement method has three objectives. First, the measured loss should indicate that the link will or will not work. Second, a subtle objective, the measured loss should indicate proper installation of the link components. Third, the measured loss should be the same with test equipment from different manufacturers.
Let's look at the first objective: The measured loss should indicate that the link will or will not work. The EF method of defining launch power distribution is a compromise of the distribution for the two types of multimode light sources: LEDs and VCSELs. In this characteristic, compromise, the EF method is no different from the coupled power ratio (CPR) method required by TIA/EIA-568-B. However, the EF method is a compromise that is different from that of the CPR method of TIA/EIA-568-B.
There are two consequences of this compromise. The first consequence is that the measured loss will be less than the loss experienced with an LED transmitter (100Base-F or 100Base-SX). The risk with testing for loss from LED transmitters is that an acceptable measured loss may not result in proper operation. Thus, troubleshooting and installation costs can increase.
The second consequence is that the measured loss will be greater than the loss experienced with a VCSEL transmitter (1000Base-SX or 10GBase-SX). The risk with testing for loss from VCSEL transmitters is that an unacceptable measured loss may not result in improper operation. Thus, installation or rework costs can increase unnecessarily.
Of course, if the link components (cable, connectors and splices) are properly installed, the measured loss is likely to indicate proper operation for either type of light source. But it is this objective -- determination of proper installation -- that is the second objective of any test method.
Let's look at the second objective: The measured loss should indicate proper installation of the link components. Both the EF and CPR methods have the same difficulty with indicating proper installation. This difficulty results not from the test method, but from the TIA/EIA-568 standard. The TIA/EIA-568 standard recommends a method of calculation of the loss acceptance value. This method uses the maximum attenuation rate and connector loss values. This method conflicts with the reality of proper product installation. Properly installed cables, connectors and splices will have actual losses that are closer to the typical losses than they are to the maximum losses. Thus, neither EF nor CPR test methods can fulfill the second objective of a test method.
Such fulfillment requires the designer and installer to establish their own method. In our fiber-optic installation and design training programs and texts, including Successful Fiber Optic Installation - The Essentials, we at Pearson Technologies recommend a method to resolve this difficulty.
For now, let's look at the third objective: The measured loss should be the same with test sources from different manufacturers. While writing about encircled flux recently you stated, "In the meantime, there was poor correlation among labs when international round-robin testing was initially conducted. Another round-robin test is now underway." Obviously, the EF method does not yet meet this objective.
What are the network designer and installer to do? Because, apparently, losses measured with test equipment from different manufacturers do not yet agree, designers and installers should reference the TIA/EIA-568-B test method (CPR). When the EF test method is shown to create no problems for the installer and tester, the designer and installer can reference the TIA/EIA-568-C test method (EF). Of course, doing so may require purchase of new test sources and/or equipment.
We justify this recommendation with two facts. First, the CPR method of TIA/EIA-568-B does result in the same measured losses with test sources from different manufacturers. Our testing indicates that losses are with 0.05 dB of one another. this value is less than the repeatability value of 0.2 dB stated on many connector data sheets. Second, the CPR method results in the same measured loss with test sources that have a CPR ratio that is slightly outside of that defined in TIA/EIA-568-B. In 2003, testing conducted by Pearson Technologies demonstrated these two facts.
Eric R. Pearson, CFOS is president of Pearson Technologies Inc. You can reach him via email at fiberguru@ptnowire.com.
I have been following the encircled flux (EF) standard from the sidelines. From this position I do not have the entire picture. With that understanding, I offer the following information.
Any measurement method has three objectives. First, the measured loss should indicate that the link will or will not work. Second, a subtle objective, the measured loss should indicate proper installation of the link components. Third, the measured loss should be the same with test equipment from different manufacturers.
Let's look at the first objective: The measured loss should indicate that the link will or will not work. The EF method of defining launch power distribution is a compromise of the distribution for the two types of multimode light sources: LEDs and VCSELs. In this characteristic, compromise, the EF method is no different from the coupled power ratio (CPR) method required by TIA/EIA-568-B. However, the EF method is a compromise that is different from that of the CPR method of TIA/EIA-568-B.
There are two consequences of this compromise. The first consequence is that the measured loss will be less than the loss experienced with an LED transmitter (100Base-F or 100Base-SX). The risk with testing for loss from LED transmitters is that an acceptable measured loss may not result in proper operation. Thus, troubleshooting and installation costs can increase.
The second consequence is that the measured loss will be greater than the loss experienced with a VCSEL transmitter (1000Base-SX or 10GBase-SX). The risk with testing for loss from VCSEL transmitters is that an unacceptable measured loss may not result in improper operation. Thus, installation or rework costs can increase unnecessarily.
Of course, if the link components (cable, connectors and splices) are properly installed, the measured loss is likely to indicate proper operation for either type of light source. But it is this objective -- determination of proper installation -- that is the second objective of any test method.
Let's look at the second objective: The measured loss should indicate proper installation of the link components. Both the EF and CPR methods have the same difficulty with indicating proper installation. This difficulty results not from the test method, but from the TIA/EIA-568 standard. The TIA/EIA-568 standard recommends a method of calculation of the loss acceptance value. This method uses the maximum attenuation rate and connector loss values. This method conflicts with the reality of proper product installation. Properly installed cables, connectors and splices will have actual losses that are closer to the typical losses than they are to the maximum losses. Thus, neither EF nor CPR test methods can fulfill the second objective of a test method.
Such fulfillment requires the designer and installer to establish their own method. In our fiber-optic installation and design training programs and texts, including Successful Fiber Optic Installation - The Essentials, we at Pearson Technologies recommend a method to resolve this difficulty.
For now, let's look at the third objective: The measured loss should be the same with test sources from different manufacturers. While writing about encircled flux recently you stated, "In the meantime, there was poor correlation among labs when international round-robin testing was initially conducted. Another round-robin test is now underway." Obviously, the EF method does not yet meet this objective.
What are the network designer and installer to do? Because, apparently, losses measured with test equipment from different manufacturers do not yet agree, designers and installers should reference the TIA/EIA-568-B test method (CPR). When the EF test method is shown to create no problems for the installer and tester, the designer and installer can reference the TIA/EIA-568-C test method (EF). Of course, doing so may require purchase of new test sources and/or equipment.
We justify this recommendation with two facts. First, the CPR method of TIA/EIA-568-B does result in the same measured losses with test sources from different manufacturers. Our testing indicates that losses are with 0.05 dB of one another. this value is less than the repeatability value of 0.2 dB stated on many connector data sheets. Second, the CPR method results in the same measured loss with test sources that have a CPR ratio that is slightly outside of that defined in TIA/EIA-568-B. In 2003, testing conducted by Pearson Technologies demonstrated these two facts.
Eric R. Pearson, CFOS is president of Pearson Technologies Inc. You can reach him via email at fiberguru@ptnowire.com.
Wednesday, June 1, 2011
Cisco's PoE Passthrough switch powers itself
Cisco Systems has developed a Power over Ethernet Passthrough switch, which powers itself. In a video Narayanan Krishnamoorthy, a technical marketing engineer with Cisco, explains that the concept of PoE Passthrough is power coming into the switch from uplink ports that are PoE and PoE-Plus-capable. The switch uses that power to power itself, and if excess power is available, the switch allocates that power on the downlink ports.
The switch has no power supply and is cooled by convection, as is pointed out in the video. As a result, the switch is fanless and therefore quiet. Krishnamoorthy says Cisco put its best engineers on the project of developing the PoE Passthrough. A key technological breakthrough was the development of a chip to accept PoE coming through the uplink.
The in-house Cisco video, as we might expect, gushes over the switch's capability.
Take a look.
The switch has no power supply and is cooled by convection, as is pointed out in the video. As a result, the switch is fanless and therefore quiet. Krishnamoorthy says Cisco put its best engineers on the project of developing the PoE Passthrough. A key technological breakthrough was the development of a chip to accept PoE coming through the uplink.
The in-house Cisco video, as we might expect, gushes over the switch's capability.
Take a look.
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