Fiber Optic Blog

by http://www.fiber-mart.comHigh-quality internet connectivity gives people a voice, creates opportunities, and strengthens local and global economies. The need for widespread reliable internet connectivity and infrastructure is more apparent now than ever, as heavier reliance on remote work and online communication during the COVID-19 pandemic drives a dramatic surge in global internet usage. And yet, according to the 2020 Inclusive Internet Index, nearly half the world remains unconnected. 

Submarine fiber optic cables, or subsea cables, are among the most important components that enable greater connectivity, but they are not well known. They are important for global network infrastructure, connecting countries, carrying communications, and enabling commerce and education. The importance of internet connectivity to economic growth is well established, but rigorous studies quantifying the impacts are not available for many countries. Our recently announced 2Africa cable, which we are developing with regional and global partners, is one of the largest subsea cable projects in the world. It will interconnect 23 countries in Africa, the Middle East, and Europe, delivering more than the total combined capacity of all subsea cables serving Africa today. At 37,000 kilometers long, 2Africa will be nearly equal to the circumference of the Earth and will link the continent from east to west for the first time. 2Africa will greatly enhance internet capacity and connectivity at a time in which broadband traffic is growing significantly worldwide.

Growth in the demand for broadband technology are driven by trends in the global economy, as high-quality, reliable broadband is increasingly used by many industries to produce and sell goods and services. RTI International, an independent nonprofit research institute, estimates that the impact of 2Africa would likely be an increase of 0.42 to 0.58 percent in African GDP within the first two to three years of going live in 2023–2024. This estimate is based on analysis leveraging empirical evidence, market conditions and trends, and discussions with experts about the effects of broadband on the African economy.

This impact is equivalent to 26.4 to 36.9 billion USD at purchasing power parity (PPP), a metric that accounts for differences in standards of living between countries. From analyzing previous subsea cables, RTI expects to see increases in employment (including high-skilled jobs), greater efficiency and productivity for businesses, and improved access to education, healthcare, and commerce. There will likely be additional impact beyond the two- to three-year period, however, it is too soon to quantify what that impact may be. RTI’s full report about 2Africa is available here. (This research was conducted prior to the COVID-19 pandemic.) Impact of subsea cables in sub-Saharan Africa Understanding the impact of subsea cables is important for designing the policies and prioritizing the infrastructure investments that will be most effective for growth. Based on the estimates from the most current studies, subsea cables and broadband infrastructure investments are among the most effective development policies for economic growth in Africa.

The promise of subsea cables as drivers of economic growth in Africa warrants excitement about the potential economic impact of 2Africa. Today, we are releasing a series of studies by RTI International that analyze the role of subsea cables and broadband connectivity in the economic development of six countries across sub-Saharan Africa. These reports underscore the importance of subsea cables and the connectivity they enable. The six countries — Nigeria, Democratic Republic of Congo, Kenya, South Africa, Mozambique, and Tanzania — show varying degrees of positive results. Four of the six countries studied experienced notable increases in employment, with all other variables controlled for. The results show us how subsea cables and greater connectivity can drive economic growth. RTI used advanced statistical techniques paired with local insights to document the impact that subsea cables and improved connectivity have had on economic development.

The team looked specifically at subsea cable landings over the past 6 to 10 years in each country, controlling for technology trends, population characteristics, and other important factors. These findings underscore the importance of accelerating the growth in connectivity in sub-Saharan African countries. 2Africa is a continuation of our ongoing efforts to expand global network infrastructure. 2Africa is a major investment at an important time for the continent’s economic recovery and will play a large role in supporting tremendous internet expansion to underpin Africa’s growing digital economy. For regions such as sub-Saharan Africa, where more than half of all global population growth between now and 2050 will occur, we look to remove barriers to access. We will continue to collaborate with partners all over the world to help expand and improve global connectivity, close the digital divide, and strengthen economies. We will continue to study and release information about the role of subsea cables in Africa and around the world as we invest in this critical infrastructure.

by http://www.fiber-mart.comOur engineers have spent years working to keep the physical systems that power Facebook products and services cutting-edge, efficient, and capable of scaling as trends such as video and virtual reality have increased the demand for capacity. To provide the 2.7 billion people using our products with the best possible experience, we have designed more efficient servers and data centers, and we have strengthened the long-haul fiber networks that connect our data centers to one another and to the rest of the world. As we bring more data centers online, we will continue to partner and invest in core backbone network infrastructure.

We take a pragmatic approach to investing in network infrastructure and utilize whatever method is most efficient for the task at hand. Those options include leveraging long-established partnerships to access existing fiber-optic cable infrastructure; partnering on mutually beneficial investments in new infrastructure; or, in situations where we have a specific need, leading the investment in new fiber-optic cable routes. In particular, we invest in new fiber routes that provide much-needed resiliency and scale. As a continuation of our previous investments, we are building two new routes that exemplify this approach.

We will be investing in new long-haul fiber to allow direct connectivity between our data centers in Ohio, Virginia, and North Carolina. As with our previous builds, these new long-haul fiber routes will help us continue to provide fast, efficient access to the people using our products and services. We intend to allow third parties — including local and regional providers — to purchase excess capacity on our fiber. This capacity could provide additional network infrastructure to existing and emerging providers, helping them extend service to many parts of the country, and particularly in underserved rural areas near our long-haul fiber builds. Unlike a retail telecommunications provider, we will not be providing services directly to consumers.

Our goal is to support the operators that provide such services to consumers. We will reserve a portion for our own use and make the excess available to others. This means you’ll start to see a Facebook subsidiary, Middle Mile Infrastructure, operating as a wholesale provider (or, where necessary, as a telecommunications carrier). Continuing our commitment to infrastructure investmentsThis work is a continuation of our efforts to develop our network infrastructure. That work began about a decade ago, when a small team of engineers designed and built one of the world’s most energy-efficient data centers from the ground up: software, servers, racks, power supplies, and cooling systems.

 When we began building our newest operational data center in New Mexico, we built a 200-mile cable to connect that facility to the one in Texas. This underground cable is now one of the highest-capacity systems in the United States, with state-of-the-art optical fiber. The resulting cable is more efficient than other high-capacity cables, and our New Mexico data center now has another redundant path to our network.

by http://www.fiber-mart.comFiber optic networks evolved in late 20th century to cater the increasing demands of bandwidth and to allow faster communication networks. Fiber optic Transceivers use a laser as light source which transfer signals through one or more glass strands (fibers). Optical Transceivers have several advantages over the copper/electrical wire communication such as increased communication distance, more bandwidth and higher data rates. Apart from the enormous advantages that optical Transceivers offers, a few extra measures need to be taken as well, to ensure a reliable and robust network, which includes taking care of fiber bends, coupling, splicing and the use of appropriate Transceivers to communicate over the fiber optic network. Fiber optic Transceivers are available in various types and form-factors and evolved from the Gigabit Interface Converter, commonly referred to as GBIC, over Small Form-Factor Pluggable, commonly referred to as SFP up to the C Form-Factor Pluggable, commonly referred to as CFP. 

All of the above mentioned Transceivers provide the interface for the fiber optic to be terminated on the communication equipment (like a switch or router). The choice of the Transceiver depends on various factors which include: • Length of the communication link• Type of fiber optic cable being used, i.e., single-mode or multi-mode• Type of slot on the communication equipment• Bandwidth of the communication link Let us dig deeper into the evolution of the fiber optic Transceivers in the sections ahead. GIGABIT INTERFACE CONVERTER (GBIC) TRANSCEIVERThe GBIC Transceiver was first introduced and standardized in 1990 by the Small Form-Factor Committee (SFF Committee). The primary reason to develop such a Transceiver was to enable the use of fiber optic cables to connect two or more communication devices and allow more bandwidth and longer distance direct links. GBIC Transceivers usually provide up to 1Gbps duplex bandwidth over a single link, although it has been tested for speeds up to 2.5Gbps. GBIC Transceivers commonly use the SC connector to terminate the fiber optic cable.

GBIC Transceivers are also available for 1000BASE-T to terminate the common twisted pair copper cables. One of the main features of GBIC is that it is hot-swappable, i.e., one does not need to power off the communication equipment to insert or remove the GBIC. This allows the communication network to be always-on despite new links being added on it. The dimensions of the GBIC Transceiver as defined by the SFF Committee standard document are 57.15mm x 12.01mm x 30.48mm (L x H x W). The GBIC slot in the communication equipment is also designed keeping the mentioned dimensions in view. SMALL FORM-FACTOR PLUGGABLE (SFP) TRANSCEIVERSFP Transceivers were the next step in the development of fiber optic Transceivers, this one was also developed as a standard by the SFF Committee in 2001. A SFP Transceiver is much smaller in size as compared to its predecessor.

The size of the SFP slot in a communication equipment is somewhat comparable to the normal electrical Ethernet port. Dimensions given in the SFF Committee standard document are given in the following table: Transceiver width, front 13.7 mmTransceiver height, front 8.6 mmTransceiver width, rear 13,4 mmTransceiver height, rear 8,5 mmTransceiver overall length 56,5 mm It is necessary to mention here that several variants of SFPs have been developed to support higher bandwidth using the similar form-factor. In between SFP+, XFP, XENPAK, X2 are Transceivers that supports 10Gbps duplex link, QSFP Transceivers support up to 40Gbps links with a little larger size than the SFP and SFP+. C FORM-FACTOR PLUGGABLE (CFP) TRANSCEIVERTo meet the ever-growing demand for higher speed communications, engineers started working on developing a Transceiver that could support 100Gbps and higher bandwidths. In 2009, CFP MSA came out with a new standardized Transceiver called CFP which could support 100Gbps traffic. A CFP module has the dimensions of 144.8mm x 82mm x 13.6mm (LxWxH). 

A CFP Transceiver supports up to 10km link length on single-mode optical fiber cables and up to 150m on laser optimized multi-mode optical fiber cables. Variants of CFP Transceivers have also been developed as standards, CFP2 supports up to 100Gbps with a smaller form-factor and CFP4 supports up to 100Gbps with form-factor similar to QSFP Transceivers. CONCLUSIONIn light of the above mentioned details about the advancement and development of the fiber optic Transceivers, it is imperative that the trend of faster communication speeds and smaller form-factors will continue in future. Today, every other person has a smart-phone, a tablet PC, a laptop and a desktop computer which all connect to some kind of network, even the wrist watches and televisions connect to internet these days. This enormous growth in the internet’s traffic has produced the need for this development which we are seeing today in fiber optic networks. It is in near future that the current technology we have might not be enough to support the demands of the next generation smart devices, so the development and research is continuing at an even faster pace to cope up with the advancement in technology.

by http://www.fiber-mart.comCommonly, optical networks rely on Transceivers that utilize one optical fiber to transmit data and another optical fiber to receive data to and from the networking devices. Generally, this kind of data transmission raises the costs of the network deployment, however with use of the bidirectional optical WDM BIDI Transceiver, and its capability to send and receive data over one optical fiber, we can create a much more cost-effective optical networks. 

The Bidirectional Optical Transceiver or BIDI, is a type of an optical Transceiver which uses the Wavelength Division Multiplexing technology or widely known as WDM technology. The BIDI Transceiver manages to do this with the help of the integral bidirectional coupler which transmits and receives signals. The main difference that differentiates BIDI Transceivers from standard, two fiber Transceivers, is the possibility of the BIDI Transceiver to send and receive optical light data through a single fiber. This is easily illustrated in the pictures below which offer a side to side comparison between these two types of Transceivers.

The other key difference between the standard and BIDI Transceiver is the introduction of Wavelength Division Multiplexing technology incorporated into BIDI Transceivers. This technology separates the data sent and received over the same fiber based on the wavelengths of the light. However, to work at maximum level, the BIDI Transceiver must be deployed in matched pairs and tuned to match the expected wavelength of the transmitter and receiver they are transmitting and receiving data from and to. To put things in perspective, if one Transceiver is transmitting wavelengths of 1310 nm, the other side must have a receiving wavelength of 1310 nm and vice-versa. The common types of BIDI Transceivers used in today’s networks are: Bidirectional optical X2 Transceiver – Firstly designed for 10GB serial data communications. This transceiver is made of two sections with the transmitter part using a multiple quantum 1330/1270 nm Distributed Feedback Laser. The receiving part of the transceiver uses an integrated detector with preamplifier for 1270/1330 nm. This optical transceiver is mainly used in Ethernet solutions. Primarily used in older networking equipment. 

Bidirectional optical SFP Transceiver – this transceiver is most commonly deployed in high speed duplex data links over a single optical fiber. The most common optical wavelengths for this transceiver is 1310/1490 nm, 1490/1550 nm and 1310/1550 nm. Today this type of transceivers is used in optical communication for optical gigabit telecommunications and optical data bidirectional applications as follower of the GBIC Transceiver. Bidirectional optical SFP+ Transceiver – This type of transceiver is a more advanced version of the BIDI SFP Transceivers. SFP transceiver. It is designed for 10 GB deployment and distances up to 80 kilometers. Bidi variants are also available for the form factor XFP. Bidirectional optical QSFP Transceiver – This transceiver most commonly has two 20 GB/s channels with each transmitted and received at the same time over a single Multi-mode strand (OM3 or OM4). The obvious advantage of using Bidirectional Transceivers is simple. Reducing the fiber optic cable infrastructure, reducing the number of patch cords and panels and thus reducing the overall cost of the Network Solution. Even though Bidirectional Optical Transceivers cost more to purchase them, deploying them will eventually result in cutting down half of the amount of fiber per distance needed for a certain project. 

Today the Bidirectional Optical Transceivers are mainly used in FTTH/FTTB active Ethernet point-to-point connections. These connections consist of a central office, or premises equipment (PE), connecting to the CPE or widely known as Customer Premises Equipment. Active Ethernet solution uses the point-to-point technology in which each customer is connected to the PE on a dedicated fiber. In this case the use of BIDI Transceivers is essential because it provides a bidirectional communication over a single fiber by using the WDM technology making the connection simpler to deploy, troubleshoot and configure.

by http://www.fiber-mart.comIn data center environment there are many interconnections needed from regular large numbers of ports of access switches to the large bandwidth capacity ports of backbone routers with particular cases of ports facing the connections towards storage access networks. All these ports need reliable connections implementations in form of connection cables on short distances. There are two main forms of interconnection patches: AOC – Active Optical Cables and DAC – Twinax Direct Attach Cables. The target application is interconnection of top-of-rack switches with application servers and storage devices in a rack or across adjacent racks. 

Active Optical Cable (AOC) – The optical Solution AOC – Cables are constructed using optical fibers and have attached on the ends active optical components in form of optical transceivers. Their advantage consists in protection to electromagnetic perturbations, greater bandwidth capabilities and management functions embedded in the end active parts. All these features come with a proportional higher price than twinax cables. Direct Attach Cable (DAC) – The Twinax Copper Solution DAC – Cables use the twinax copper wires to transmit signals. Twinax cable is almost similar with CATV coaxial cable but not the same having two conducting wires inside covered by protective shield. They are suitable up to 10 Gbps data rates and distances up to 15 meters. At the end also a transceiver is used as a plug connector.

 The Comparison: Twinax versus Cat5 or Cat6 Ethernet Cables The advantage of twinax over short distance consists in lower transmission delay 0.1μs versus 1.5 to 2.5μs for current implementations of SFP+ DAC cables vs 10GBASE-T. The power draw of Twinax with SFP+ is around 0.1 watts, which is also much better than 4–8 watts for 10GBASE-T. Cables must not be bent below their minimum bend radius, which depends upon cable size as expressed in AWG – American Wire Gauge. What is the difference between Active and Passive DAC Cables? There are some versions of DAC which have some active modules at the respective ends. The active 10G SFP+ CU/CR DAC link utilizes a receive equalizer in the host PHY/SerDes in order to compensate for the Inter Symbol Interference (ISI), performing signal re-shaping and amplification introduced by the cable making them suitable for longer distances.

The usual distance to reach of passive DAC cables is within 7 meters for data center connectivity. The active components are available for data rates of up to 40G, passive types up to 100G. Passive cables are much less costly but require the host to do the work of driving it properly.  The new Generation: 100G Direct Attach Cables The 40GBASE-CR4 and 100GBASE-CR10 physical layers using 7 m twin-axial cable are being developed as part of 100 G Ethernet specifications by IEEE 802.3bj workgroup. IEEE 802.3bj define a 4-lane 100Gbit/s backplane PHY for operation over links consistent with copper traces on with lengths up to at least 1 Meter and a 4-lane 100 Gbit/s PHY for operation over links consistent with copper twinax cables with lengths up to at least 5 Meter. The SC282801LXM30 – BlueLAN© 100GBASE-CR4 QSFP28 Direct Attach Cable (passive), 1 to 2 Meter, AWG 30 – This item is currently the DAC solution with the highest bandwidth with a total throughput of 100 gigabits per second.