Tag Archive for Ethernet

Out of This World Ethernet

Out of This World EthernetA while ago I wrote about Ethernet marching on. The IEEE had ratified the IEEE 802.3bp Ethernet standard which addresses how Ethernet operates in harsh environments. Now Ethernet has been installed in the harshest environment where we live, the International Space Station. During an April 2019 Extravehicular Activities (EVA), U.S. astronaut Anne McClain and Canadian astronaut David Saint Jacques upgraded the International Space Station’s communication systems by installing Ethernet cables.

Cabling Install and Maintenance reports that during a six-plus-hour spacewalk the astronauts installed Ethernet cables on the exterior of the space station to upgrade the wireless communication system and to improve its hard-wired communication system.

CBS News says the spacewalker’s connected Ethernet cabling at the forward end of the station’s  U.S.’s primary research laboratory for U.S. payloads module (Destiny module) that will extend wireless connectivity for science instruments mounted outside the space station.

NASA Tweeted a video clip of the cable installation during which the narrator explained, “... They’ll be de-mating and mating some cables to provide additional Ethernet to the International Space Station.

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Pulling more cable to expand wireless coverage – nice to know some things are truly universal. Whether you call it cable pulling, or mating cables, the truck-roll cost to the ISS must be pretty steep. At least NASA installers don’t need ladders.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedInFacebook, and Twitter. Email the Bach Seat here.

Why Shielded Cables?

Why Shielded Cables?With high bandwidth applications emerging in and out of the data center, the need for shielded cable has increased. Many of these new installations are in harsh environments.  Robotic equipment, motors, generators, air conditioners, fluorescent lights, printers, and they often generate a large amount of EMI (Electromagnetic Interference) and RFI (Radio Frequency Interference). You may need to install shielded cables in these harsh environments.

interference will cause increased errorsEMI and RFI can cause crosstalk between circuits and interfere with data transmission on a copper cable. The interference will cause increased errors resulting in mire network traffic due to packet retransmissions, and downtime.

Shielded cables reduce interfernece

EMI is an unwanted signal that is induced into the cable. EMI typically comes from a source that is external to the cable, such as an electrical cable or device. Cables can be both a source and receiver of EMI. As a source, the cable can either conduct noise to other equipment or act as an antenna radiating noise. As a receiver, the cable can pick up EMI radiated from other sources.

RFI is a disturbance that affects an electrical circuit due to either electromagnetic conduction or radiation emitted from an external source. Conducted RFI is unwanted high frequencies that ride on the AC waveform. Radiated RFI is emitted through the air.

Ethernet cables can be shielded to deal with EMI and RFI.  The shield surrounds the inner signal carrying conductors. Shielded Ethernet cables can deal with interference in two ways. It can reflect the energy, or it can pick up the interference and conduct it to ground. Both methods use shielding to cut the EMI and RFI reaching the twisted pairs located under the shielding. Whether the EMI/RFI is reflected off the shield or “rides” the shield to ground, some energy can still pass through the shielding, but since it is so highly attenuated it will not cause interference.

Types of shielded cables

Two basic types of shielded cables are available. The first are cables with an overall shield known generically as STP. STP cable may be made either with a foil or a braid for the shield. STP cables with an overall foil are often known as FTP. In practice, FTP and STP cables may be interchanged with no apparent difference in performance according to BlackBox

Cable types
The second type of shielded cable is S/STP. S/STP cables have a shield around each individual pair and an overall outer shield. BlackBox says the purpose of the inner shields is to cut the Alien Cross Talk parameter in CAT7 and CAT6a systems.On both STP and S/STP the primary task of the outer shield is to resist external RF noise such as electrical spikes.  S/STP cables may also have an extra braid for strength and to simplify connection to the metal shields around the connectors.
Cable constructionTo reduce EMI/RFI interference, shielded Ethernet cables must use shielded connectors to maintain the benefits of STP cabling. High-quality shielded cable includes a drain wire to provide grounding that cancels the effects of EMI and can ease termination of the cable shield for crimping or soldering.

Redi WattProper Ground connections

The shielded cable system must have proper ground connections for the shields. Incorrect grounding opens the possibility for ground loop currents and associated interference to the Ethernet signal. In the worst cases with no proper grounding, the shields can actually act as antenna broadcasting high-frequency signals out into the environment interfering with electronic equipment and allowing external detection of the Ethernet data.

Standards bodies have requirements for shielded Ethernet systems. The American National Standards Institute (ANSI) specifics how shielded communications cables are properly grounded. Normal practice says the cable shields should be grounded in the telecommunications closet (TC). Typically, the cable shield is grounded through the connector to the patch panel. Then the panel is grounded to the rack, which is grounded to the telecommunications grounding busbar in the TC. Do not ground the cable shield at the work-area outlet. Fortunately, many of today’s shielded outlets automatically connect to the patch panel’s ground so there’s no need to set up ground paths for each cable.

ISO/IEC requires that shielding must be complete for an entire channel, shielded and shielded cables, connectors or network controllers should not be mixed.

Cable Types

Category cable types comparison.
Max Data RateMax TX RateMax LengthSheildingYear IntroducedStatus
Cat 310Mbps16MHz100mNo1983Obsolete
Cat 5 1,000Mbps100MHz100mOptional1995Obsolete
Cat 5e1,000Mbps250MHz100mOptional2001Obsolete
Cat 6 10,000Mbps500MHz100mOptional2002
Cat 6a10,000Mbps500MHz100mOptional2008
Cat 7 10,000Mbps600MHz100mRequired2002Not recognized by TIA
Cat 7a10,000Mbps1GHz100mRequired2010Not recognized by TIA
Cat 8.140,000Mbps2GHz30mRequired2016Backward compatible with Cat 6A
Cat 8.240,000Mbps2GHz30mRequired2016Not recognized by TIA

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interference is not a new problem. It dates back to the earliest communication systems. In 1881 Alexander Graham described the interaction between many twisted pairs in US Patent 244,426.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedInFacebook, and Twitter. Email the Bach Seat here.

Switch Sales Stalled

Switch Sales StalledThe stats for sales of network switches are in for Q4 2017. Only one of the top 5 networking vendors was able to squeeze out a small gain in switch sales. The data comes from New York-based NPD. NPD tracks monthly network switch sales data from the sales channel, distributors, and resellers in North America.

The article on CRN notes that the total number of switches sold through the channel in the quarter was 514,095. The number is up slightly from 510,822 in the fourth quarter of 2016, according to NPD. Here are the five vendors that sold the most switches through the channel in the fourth quarter, according to NPD.

D-Link Systems

D-Link logoTaiwan-based D-Link Systems (2332:TT) sold 25,259 switches during the fourth quarter, according to NPD statistics. That total kept the company steady with the same period in 2016 when it sold 25,277. D-Link did not have a switch model among the top 10-selling units during the quarter. Its market share was unchanged at 4.9%, CRN said.

TP-Link switch sales

According to NPD’s data, of all the five best-selling switch brands, TP-Link saw the steepest decline during this period. The company based in Shenzhen, China sold 26,023 switches in Q4 ’17 compared with 29,798 in Q4 ’16. That’s a 12.7 percent year-over-year decrease. There is one bright spot for the firm, the article reports that the company’s TLSF1005D Ethernet switch was the third-best-selling unit during the quarter. But that was not enough to prevent a market share decline from 5.8 percent in 2016 to 5.1 percent in 2017.

Hewlett Packard Enterprise switch sales

HPE LogoThe news from NDP is not good for former networking giant Hewlett Packard Enterprise (HPE) either. The Palo Alto, CA-based firm saw a 1.8 percent decline in switches sold from 55,923 in Q4 ’16 to 54,941 switches in Q4 ’17. The quarter’s total was enough for a 10.7 percent market share, down slightly from the year-ago period. No HPE switch models were among the top 10 for the quarter, according to NPD.

Netgear sales

CRN reports that sales also slipped for Netgear. The number 2 switch company saw its market share dip from 18.3% to 17.9% year over year. The California-based firm sold 92,274 switches through the channel in the fourth quarter, down slightly from the 93,531 it sold in the same period a year ago, NPD said. Netgear had four switches in the top 10-best-selling switches during the quarter, including the top two models, the FS105 and GS105NA five-port models.

Cisco switch sales

Cisco (CSCO) was able to hold on to the #1 switch vendor position according to NDP. It sold 225,051 units during the period, a 5.7 percent increase that boosted the company’s market share to 43.8 percent from 41.7 a year earlier. Six of the top 10 best-selling switches in the quarter were Cisco Catalyst‘s led by the WS-C2960X 24– and 48-port models.

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What happened to the network switch market? It’s still reeling from the 2007/08 recession and the Wi-Fi takeoff. Other than the Cisco switches, most of the top switch models sold were unmanaged, desktop switches limited to 100 Mbps uplinks. These types of switches make it OK to randomly add an unauthorized switch at the desktop and POOF there does your data. These desktop switches with their limited feature set don’t include Spanning Tree, so users can create a network loop and take down the whole network segment.

Not much to shout about.

Where are the vendors? Brocade? Extreme? Juniper? Dell? I am old enough to remember when switch manufacturers had a #2 strategy. 3Com, Lucent, Bay/Nortel all came into my office and said they wanted to #2 – now they are gone.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedInFacebook, and Twitter. Email the Bach Seat here.

Whats Up With Cisco?

Whats Up With Cisco?What is up with Cisco? Their fiscal results for 2017 Q3 showed revenue of $11.9 billion, a 1% decline in revenue, compared to last year. This is the 6th consecutive down quarter. The networking goliath also issued downward guidance for 2017 Q4. They estimated a revenue declines of 4-6% year-over-year.

Cisco logoOn the earnings call, Cisco CEO Chuck Robbins blamed several factors for the lower guidance. He cited:

  • “A pretty significant stall right now” in the U.S. federal public sector.
  • Service provider revenues were down in Mexico.
  • United Kingdom business is being dampened by currency issues.
  • Middle East, there is “pressure… relative to oil prices.”

Cisco layoffs

Then there are the layoffs. Cisco buried the announcement in a footnote in the company’s SEC 8-K report that 1,100 more layoffs are coming. That is on top of the 5,500 announced in August 2016.

In May 2017, we extended the restructuring plan to include an additional 1,100 employees with $150 million of estimated additional pretax charges.

Cisco layoffs

According to SDXCentral, the Cisco CEO stressed several times on the earnings call, that the company is transitioning to more software and subscription-based business. He declared,

I am pleased with the progress we are making on the multi-year transformation of our business.

These weak financial results and the move to a subscription-based business have fed speculation about the future Cisco business model. TechTarget speculates that Cisco may go so far as to separate the Network Operating System (NOS) from the hardware. They contend the move would be a dramatic departure from Cisco’s traditional business model of bundling high-margin hardware with its NOS. The author believes that market trends will likely force the vendor to release an open NOS.

Open NOS

Cisco 3750 switchTechTarget cites reports from The Information that a hardware-independent NOS called Lindt is coming. Reportedly Lindt will run on a white box powered by merchant silicon. According to the article, a number of market trends are driving the move to a hardware-independent NOS.

The first market trend forcing Cisco’s hand is the company’s declining dominance of the Ethernet switch market. Since 2011, the company’s share has dropped from 75% to less than 60% last year, according to the financial research site Trefis. The decline is important to Cisco’s bottom line. Switches accounted for 40% of Cisco’s product sales in 2016, 30% of net revenues, and 20% of the company’s $162 billion valuation.

Infrastructure as a ServiceCisco’s weakening performance in switching is tied to the second market trend forcing Cisco to release a hardware-independent NOS. Its customers are turning to public cloud providers, Amazon (AMZN) Web Services, Microsoft (MSFT) Azure, and IBM (IBM) SoftLayer, for their IT infrastructure. The more enterprises subscribe to infrastructure as a service, the less networking gear they need in their data centers.

Cloud computing

The shift to cloud providers is found in the latest numbers from Synergy Research Group. Revenue from public cloud infrastructure services is growing at almost 50% a year. In the fourth quarter of last year, revenues topped $7 billion.

 cloud providers are building open networking hardware and softwareThe third market trend forcing Cisco to a hardware-independent NOS is enterprises that were Cisco’s largest customers are now competitors. Enterprises and cloud providers are building open networking hardware and software to replace inflexible proprietary systems that lock them in. Those companies include large financial institutions, like Bank of America, Goldman Sachs, and Fidelity Investments. As well as communication service providers, AT&T (T), Deutsche Telekom, and Verizon (VZ).

The technology shift is driving an enormous amount of spending on IT infrastructure. Worldwide spending on public and private cloud environments will increase 15% this year from 2016 to $42 billion, according to IDC. Meanwhile, spending in Cisco’s core market of traditional infrastructure for non-cloud data centers will fall by 5%.

White boxes

Arista NetworksWhile Cisco is ignoring the trend away from proprietary hardware, the article says Cisco’s rivals are embracing it. Juniper (JNPR) and Arista (ANET) have released versions of their NOS for white boxes favored by cloud providers and large enterprises. Both companies reported year-to-year revenue growth in switching last year. Even Cisco’s patent lawsuit against upstart Arista was set back by the courts.

Rohit Mehra, an analyst at IDC hypothesized that Cisco’s resistance to change is likely due to fear that giving customers other hardware options would accelerate declining sales in switching. “There would be potentially some risk of cannibalization in the enterprise space,” he added.

Cisco insists its customers are not interested in buying networking software that’s separate from the underlying switch. The Cisco spokesperson told TechTarget:

TCisco insists its customers are not interestedhe vast majority of our customers see tremendous value in the power and efficiency of Cisco’s integrated network platforms, and the tight integration of hardware and software will continue to be the basis of the networking solutions we offer our customers

TechTarget adds that Cisco doesn’t say the article is wrong. Instead, the company falls back on a corporate cliché for refusing to discuss a media report. “We don’t comment on rumor or speculation,” a Cisco spokesperson said.

The networking market is evolving away from the hardware that Cisco depends on for much of its valuation. Cisco will resist changing its market approach for as long as possible. But in the end, the company will have to become a part of the trend with an open NOS capable of running on whatever hardware the customer chooses.

Cisco’s own problems

Rather than change its model for selling networking gear, Cisco has spent billions of dollars on acquisitions over the last few years to create software and subscription-based businesses in security and analytics. But Cisco’s software push has yet to pay off with 5 conservative down quarters.

Finally, Cisco just recently patched a flaw in IOS software that affected more than 300 models of its switches. Despite issuing an advisory on March 17, Cisco did not release the patch for this vulnerability until May 8, 2017. The Cisco vulnerability was part of the Vault 7 WikiLeaks dump of alleged CIA hacking tools.

Alleged CIA hacking toolsThe vulnerability, rated a critical 9.8 out of 10 by the Common Vulnerability Scoring System, is in the Cluster Management Protocol, or CMP. could allow a remote, unauthenticated attacker to reload devices or execute code with elevated privileges. This vulnerability can be exploited during Telnet session negotiation over either IPv4 or IPv6.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedInFacebook, and Twitter. Email the Bach Seat here.

Limes in Your Data Center

Limes in Your Data CenterTimes are changing in the data center. For decades data centers were wired with orange multi-mode fiber optic cable. MMF is the choice for the data center connections because it is smaller and faster than copper and cheaper and more forgiving than single-mode fiber optic cables typically used for long-haul transmissions. The orange flavor of MMF was pulled into data centers to deploy Gigabit Ethernet.

multi-mode fiber optic cableThis type of MMF would work with links up to 600 meters. MMF uses the 850 nm and 1300 nm wavelength to transmit data. The typical MMF is 62.5/125 µm which means it has a core size of 62.5 micrometers (µm) and a cladding diameter of 125 µm, OM1 (“OM” stands for optical multi-mode). The second generation of MMF is 50/125 µm (OM2). These cables used LED transmitters. Newer installations often used laser-optimized 50/125 µm multi-mode fiber (OM3). MMF that meets this designation has enough bandwidth to support 10 Gigabit Ethernet (GigE) up to 300 meters.

10 GigE is a great technology, but many organizations have outgrown it. New variants of Ethernet can reach speeds of 25 Gbps, 40 Gbps, 100 Gbps, and soon, up to 800 GigE is needed to keep up with the new requirements of enterprise and cloud data centers.

cloud data centersThe industry determined that a new type of fiber was needed to physically pass the bits back and forth at these new speeds and yet maintain backward compatibility with older installations. In October 2016, the international cabling standards development body International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) decided that the new standard would be called OM5.

Cabling Installation & Maintenance magazine reports that the new OM5 standard was developed to meet the increasing bandwidth demands but keep up compatibility with older MMF installations, “The standard specifies 50/125-micron laser-optimized fiber that is optimized for enhanced performance for single-wavelength or multi-wavelength transmission systems with wavelengths in the vicinity of 850nm to 950nm.”

OM5 fiber is 50 micron core, laser optimized multimode fiber (LOMF)Sr. Fiber Product Manager at Legrand Randy Harris, explained that OM5 fiber is a new type of 50-micron core, laser-optimized multimode fiber (LOMF) designed to provide better performance for applications using wavelength division multiplexing (WDM). It operates over a wider window in the range of 850nm to 953nm to support at least four wavelengths. Swiss-based cabling provider R&M says OM5 fiber-optic cabling supports duplex transmission by sending four wavelengths over a single multimode fiber to create future bandwidths up to 200 Gbps.

Cindy Montstream explained in an article published in Cabling Installation & Maintenance magazine in September 2016,

The 40 GE SWDM4 and 100 GE SWDM4 specifications support transmission over duplex OM3, OM4, and OM5 multimode fiber types. Maximum reaches vary from 75 to 440 meters depending on data rate and fiber type. The group added that in the future, SWDM technology could be leveraged to enable 200-, 400-, and 800-Gbit/sec Ethernet traffic on multimode fiber cabling as well.

In June 2016, a Telecommunications Industry Association (TIA) TR-42 subcommittee approved the new standard, which specifies wideband multimode fiber. In February 2017, the TIA TR-42.12 Optical Fibers and Cables subcommittee approved lime green as the OM5 jacket color. At that time it also approved a project to develop Addendum 2 to the TIA-598-D standard.

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The evolution of Ethernet is driving changes in the data center. The IEEE has developed a couple of new standards for Ethernet, which I wrote about here. The new standards include IEEE 802.3by, which covers 25 Gb/s switch interconnects for data centers.

In well-done cable installations cables can be distinguished by jacket color:

  • Orange jackets indicate legacy 62.5/125 µm (OM1) and 50/125 µm (OM2) fiber-optic cabling
  • Aqua jackets show 50/125 µm “laser-optimized” OM3 and OM4 fiber fiber-optic cabling
  • Lime-green jackets  50/125 µm “laser-optimized” OM5 fiber-optic cabling
  • Yellow jackets indicate single-mode fiber-optic cabling

It took decades to install all the orange old-school MMF, it is going to take several more decades to get it all uninstalled.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedInFacebook, and Twitter. Email the Bach Seat here.