40G vs 100G: Which One Is Worth the Investment?

Today, the trend for high-speed data transmission and high-bandwidth is overwhelming. Some years ago, people had witnessed upgrading from 10Mbps Ethernet to 100Mbps Ethernet. And the migration from 1G to 10G was happened not very ago. But now, whether you believe it or not, prepared or not prepared, 40G and 100G have already on the way. To upgrade to 40G or skip it and directly migrant to 100G has become a question for many data center mangers and IT engineers. Here, in this article, you may find some clue you want.

The Rise of 100G

To begin with, it has to be made clear that the market trend is 100G Ethernet, which will eventually become the mainstream in the future. The strong demand in 100G Ethernet is being driven by cloud services and hyper-scale data centers. And there is a demand for lower-priced 100G pluggable transceivers from data center customers. Currently, the market transition to 100GE is in full swing, fueled primarily by the seemingly insatiable need for networking bandwidth by hyper-scale data centers and cloud services. As it has been shown in the picture below, 100G Ethernet transceivers will exceed 15 million units a year.

100G market

This tremendous growth in deployments by a small number of key customers, together with a large number of suppliers competing for these orders, will undoubtedly drive down the cost of 100GE modules rapidly. It is predicted that the cost of 100G transceiver is expected to decline by 75% in the next couple of years. In the meantime, Facebook has publicly set a target cost of $100 for a 100G transceiver with a reach of less than 2km. While the Facebook target appears to be years away, we believe that a 70% cost reduction in 2 years is possible. By that time, the 100G transceivers will be more affordable.

Why not 40G?

If you ask me why 40G Ethernet will be obsolete? The short answer is “cost”. From the technical point, The primary issue lies in the fact that 40G Ethernet uses 4x10G signalling lanes. On UTP, 40G uses 4 pairs at 10G each. Early versions of the 40G standard used 4 pairs, but rapid advances in manufacturing developed a 4x10G WDM on a single fiber optic pair. Each 40G SFP module contains a silicon chip that performs multiplexing so that the switch see 40 gigabits in and 40 gigabits out. It’s similar to Coarse Wave Division Multiplexing when using fiber. When you buy a 40G cable or QSFP, you are paying for the cost of the chip and software, plus the lasers, etc. When using 25/50/100G, the “lane speed” is increased to 25 gigabits per second. For 100G Ethernet, there are four 25G signalling lanes. It’s cheaper to buy 100G with four lanes rather than 40G with a four-lane MUX.


Scale up to 100G with FS 100G Optics Solution

As one of the leading providers in optical communication , FS provides customers with 100G optics that are manufactured at the highest quality of standards in the industry, including QSFP28, CFP, CFP2, CFP4, 100G patch panels, 100G switches, etc. Part of the products are listed as follow:

Model ID Description    Price


Juniper JNP-QSFP-100G-SR4 Compatible 100GBASE-SR4 850nm 100m Transceiver

   US$  269


Cisco Compatible QSFP28 100GBASE-SR4 850nm 100m Transceiver

   US$  269


Juniper Networks CFP-100GBASE-SR10 Compatible 100GBASE-SR10 850nm 150m Transceiver

   US$  1,500

100G Ethernet are racing to market and will finally takeover the 40G market. Don’t hesitate to migrate your network to the 100G Ethernet to embrace the future technology.

100G Coherent CFP Modules for Metro Network Applications

Due to the rapid increase of communication traffic, the requirement for core networks to handle larger capacity and longer distance on their links has led to a spread of 100G optical networks. For this environment, service providers are adopting coherent transceivers for their 100G DWDM backbone applications. Until recently, coherent CFP/CFP2 DWDM optical transceivers had been the technology of choice for transporting 100G traffic over long distances or as part of a DWDM network. This paper will mainly discuss 100G coherent CFP modules for metro network application.

Coherent Technology: Making 100Gb/s Available

Moving from 10Gb/s to 100Gb/s line speeds comes with technical challenges. Coherent technology had been investigated for optical transmission since the 1980s as a means to increase transmission distances. By 2010 to 2011, the technology had reached a point of market maturity. At this time, it could genuinely allow 100G coherent signals. This result forms the foundation of the industry’s drive to achieve transport speeds of 100G and beyond, which helps to deliver Terabits of information across a single fiber pair at a lower cost. Until now, coherent technology has been mainly deployed in long-haul networks, and it is now starting to be deployed in metro networks.

Capacity Enabled by Coherent Technology

Figure 1: Capacity Enabled by Coherent Technology

Metro Requirements for 100G

100G rates were initially deployed in the long-haul and core networks. In the Metro, 10G is still the most dominant rate. In the coming years, the trend toward aggregation into 100G in the larger metro areas or data center connectivity will become more significant. The metro covers a broad range of distances: the metro regional and metro core cover distances of 500-1000 km and 100-500 km respectively, while the metro access links are generally point-to-point connections shorter than 100 km. Although these distances are shorter than long-haul links, the characteristics of metro network- including flexible protocol support, higher granularity of signal rates and increased number of nodes- create the requirements for 100G rates.

Three Types of Metro Network

Figure 2: Three Types of Metro Network

100G Coherent CFP Modules for Metro Network Applications

While metro and long haul applications have different requirements, the lower-cost 100G technology for the metro is demanded for service providers. To achieve this feat, equipment vendors consider coherent CFP as the ultimate solution for metro 100G deployments. Coherent CFP 100G can overcome optical transmission impairments and still achieve acceptable performance.

Scenario 1: 100G Multi-Channel DWDM Networking

An Architecture of Coherent CFP for 100G Deployment

Figure 3: An Architecture of Coherent CFP for 100G Deployment

As shown in Figure 3, since the 100G rates are more susceptible to dispersion, they would require extra dispersion compensation and optical power boost. Thus an extra 100GHz DWDM multiplexer is first used to combine all the 100G rates together followed by a combined dispersion compensation and amplification stage. This architecture conveniently supports the ‘pay-as-you-grow’ model for service providers. When the bandwidth is exhausted, the existing legacy 10G channels may be seamlessly interchanged with 100G services. The same remaining components can even be reused to extend the data rate up to 2.4 Tb/s.

This scenario would require 24 differently colored CFP 100G transceivers deployed together with the already existing 48 channel 100 GHz DWDM multiplexer. All the 100G services are first multiplexed together such that only one dispersion compensation and amplification stage suffices. Clearly, such a network architecture provides higher density with capability to reuse existing infrastructure with flexibility while remaining cost friendly.

Scenario 2: 100G Distance Extension Solutions

100G Coherent DWDM Transport by Using SFP+ OEO Transponder

Figure 4: 100G Coherent DWDM Transport by Using SFP+ OEO Transponder

In this scenario, the switch was tested with SFP+ OEO transponders for simple distance extension solutions. The 100G output signals from the switch are converted to DWDM signals that can be transmitted over longer distance. The solution removes the distance limitations by using a coherent CFP module to connect the output signal to the line fiber and carry the signal over longer distances.

As shown in Figure 4, to achieve higher cabling density with Cisco CFP 100G optics, the architecture mixed a 16 channels dual fiber DWDM Mux Demux which can be used for CWDM/DWDM hybrid and 8 channels dual fiber CWDM Mux Demux, by adding MTP harness cable and WDM SFP+ OEO converter to transfer the regular SR wavelength to DWDM wavelengths. Therefore, building a long distance 2500km DWDM networks in coherent CFP 100G transceiver and cost effective way will be achieved.


Coherent CFP 100G transceivers provide cost-effective electronic equalization of fiber impairments and extensive performance monitoring capabilities that enable easy installation and network management. These benefits help service providers meet bandwidth demand growth while reducing the total cost of ownership.

10G Ethernet: 10GBASE-T or 10G SFP+?

10GBASE-T has been available as an add-in card in servers, switches and network interface cards (NICs) since 2008, and it has been widely adopted since 2012. It is highly praised for its advantages which include lower cost than 10G fiber, cost-efficiency of using existing MAC (Media Access Control), easier migration from 1GBASE-T to 10GBASE-T, and the ability to deliver PoE (Power over Ethernet). Does that mean we should all turn to use 10GBASE-T now? And what are the 10GBASE-T cable requirements? Every application differs, let’s see some specific cases in short-reach applications.

10G copper or fiber

Where Can 10GBASE-T Be Used?

When building a 10G network, the link can be either copper or fiber. If using 10GBASE-T cable, the places are required to be in the Data Center or Horizontal areas (in building, including wiring closet). But it is not suited for Vertical (riser links) applications within building, or campus & metro applications.

Cases for 10G Ethernet Connections

Case 1: Connecting a switch with only SFP+ ports to a switch with only 10GBASE-T ports.

10GBASE-T cable 1

When the distance of these two switches are less than 30 m, which is the max. link distance for 10GBASE-T copper SFP+ module, the desired connection for them can be made by using a 10GBASE-T module and a Cat6a cable. It’s the simplest solution for this case.

Case 2: Connecting two switches with only 10GBASE-T ports.

10GBASE-T cable 2

Connecting two switches with all 10GBASE-T ports are as simple as placing the plug into its mating socket. One Cat6a Ethernet cable is born for such a connection and that is why it is called the standard 10GBASE-T cable. By using a Cat6a cable for 10GBASE-T, it can reach up to 100m distance.

Case 3: Connecting two switches with only SFP+ ports.

10GBASE-T cable 3

There are three choices for connecting two complete SFP+ switches. For distances between 30 m to 400 m, it is recommended to get two 10GBASE-SR SFP+ modules for each switch and connect them with a OM3/4 LC duplex multimode fiber patch cable. The second is to use two 10GBASE-T SFP+ modules and Cat6a cable. If the link is as short as 7 m, it is suggested to use a low cost 10G SFP+ direct attach copper (DAC) cable.

Case 4: Connecting switches with both SFP+ and 10GBASE-T ports.

10GBASE-T cabling 4

When the two switches both have SFP+ and 10GBASE-T ports, you will be free to use methods from Case 1 to Case 3 above. But in my experience, it would be better to use the 10GBASE-T copper ports first, and save the SFP+ ports for possible future connections to an optical network for longer transmission distance.

Words in the End

10GBASE-T is taking its way to being more extensively used on network gears without a doubt, and cost for deploying 10GBASE-T equipment will be lowered with its wide spreading. Know the requirements for 10GBASE-T cabling is necessary for correctly choosing between 10GBASE-T or 10G SFP+ in practical usage. After all, cost-efficiency is very important in large-scale deployment.

Advantages and Disadvantages of OM5 Fiber in Data Center

As the continuously increased bandwidth demand, the types of fiber patch cable are also updating quickly. OM5 fiber cable, also known as WBMMF (wideband multimode fiber), has arrived to meet the growing bandwidth requirements. However, there are different opinions on whether the adoption of OM5 fiber will benefit today’s data center. This post will focus on the advantages and disadvantage that OM5 brings for data centers.

om5 patch cable

Trends in Data Center Deployment

With the cloud computing and web services continuing to drive bandwidth need, data rates grow from 10G, 40G to 100G and beyond in many data center networks. According to the Cisco global cloud index, nearly 99 percent of global traffic will pass through data centers by 2020. That means higher bandwidth, faster services and greater access are required for data center deployments. Therefore, advanced technologies including fiber patch cable and optical transceivers will be needed for performance-improving in data centers.

Will OM5 Fiber Benefit Data Center?

OM5 fiber is a new generation of multimode fiber. It was just standardized in several months ago. Different from OM1, OM2, OM3 and OM4, OM5 fiber is designed to work over a wide range of wavelengths between 850 nm and 950 nm. And it supports SWDM (shortwave wavelength division multiplexing) technology which can reduce fiber counts in optical transmission. Here are the advantages and disadvantages of OM5 fiber cable in data center.

om5 fiber cable


Firstly, it cannot deny that the emergence of OM5 is to meet the high bandwidth challenges. At this point, OM5 will definitely benefit data centers in some degree. The main advantages are in the following part.

Compatibility—OM5 cable has the same fiber size of OM4 and OM3, which means OM5 is fully compatible with OM3 and OM4 fiber. In other words, OM5 cabling supports all legacy applications in existing data center infrastructures. If a service provider wants to use OM5 for high speed data center, big changes will not be needed for existing cabling.

Distance—multimode patch cord is often the first choice for short reach connections. As we know, OM4 patch cord can support link length up to 100m with 100G-SWDM4 transceivers. While OM5 can extend the reach to 150m with the same types of fiber optic transceivers, providing another better choice for data center optimization.

Cost—when it comes to data center building, the cost is an important parameter to consider. OM5 cable is beneficial for data center deployments. Compared to single mode fiber cable (SMF), multimode fiber cable (MMF) is more cost-effective, because in most data centers, short reach connection are common. Besides, OM5 provides optimal support of emerging SWDM applications which reduce the amount of fibers needed for high speed transmissions.


Each coin has two sides. Though OM5 fiber cable can benefit data center building, there are still some problems at present. It’s known to us that OM5 has just been standardized earlier this year. Even though many optical vendors have introduced OM5 fiber patch cables, in the market, the price is a little higher than OM4. And the production of the corresponding optical transceiver like 100G-SWDM4 is still limited. All these restrict the further adoption of OM5 fiber cables.


It’s getting more costly for fiber optic cabling systems in data centers. As a new MMF type, OM5 offers improved performance over popular OM4 and OM3. With the development of OM5 technology, it will bring more benefits for data centers.

Point-to-Point VS Structured Cabling: Which One Is Best for You?

With the emergence of the Internet of Things, the cloud and mobility, much of the conversation about network connectivity is focused on wireless. However, cabling isn’t going away. Requirements are evolving, but cabling is still an essential component of any IT environment. Because the life-cycle of a cabling system is typically much longer than most of your IT infrastructure, it is important to understand the primary cabling methods and plan carefully. This article will make a comparison between two basic cabling methods: point-to-point cabling and structured cabling.

What Is Point-to-Point Cabling?

Point-to-point cabling refers to a data center cabling system comprised of “jumper” fiber cables that are used to connect one switch, server or storage unit directly to another switch, server or storage unit. A point-to-point cabling system is adequate for a small number of connections. However, as the number of connections in a data center increases, point-to-point cabling lacks the flexibility necessary when making additions, moves or changes to data center infrastructure. When the first data centers were built, end user terminals were connected via point-to-point connections. This was a viable option for small computer rooms with no foreseeable need for growth or reconfiguration. As computing needs increased and new equipment was added, these point-to-point connections resulted in cabling chaos with associated complexity and higher cost. Therefore, there is a downside to point-to-point cabling. However, the point-to-point cabling is surfacing again with the use of top of rack (ToR) and end of row (EoR) equipment mounting options. ToR and EoR equipment placement relies heavily on P2P cables, which can be problematic and costly if viewed as a replacement for standards-based structured cabling systems.

p2p cabling

What Is Structured Cabling?

As it has been mentioned before, point-to-point cabling had aroused many problems. In response, data center standards like TIA-942-A and ISO 24764 recommended a hierarchical structured cabling infrastructure for connecting equipment. Structured cabling is a comprehensive network of cables, equipment and management tools that enables the continuous flow of data, voice, video, security and wireless communications. Instead of point-to-point connections, structured cabling uses distribution areas that provide flexible, standards-based connections between equipment, such as connections from switches to servers, servers to storage devices and switches to switches. Structured cabling is designed to meet Electronic Industry Alliance/Telecommunications Industry Association (EIA/TIA) and American National Standards Institute (ANSI) standards related to design, installation, maintenance, documentation and system expansion. This helps to reduce costs and risk in increasingly complex IT environments.

Comparison Between Point-to-Point and Structured Cabling

Traditionally, point-to-point cabling has been used in the manufacturing sector to establish a direct connection between devices and automation and control systems. However, point-to-point cabling lacks the flexibility, reliability, manageability and performance required for the exploding number of connections within today’s networks.

Structured cabling provides the flexibility that point-to-point does not, as well as the capability to support future technologies, faster connections and more intelligent networks. Although structured cabling has long been the preferred approach in IT, we cannot deny point-to-point cabling completely. Here, the pros and cons of selecting a structured cabling implementation versus point-to-point implementation are listed in the picture below:


Cabling is among the most important considerations for organizations managing a data center, and investing in the right technologies to enable flexibility and optimal performance is key. Although there are several instances where point-to-point Top of Rack or End of Row connections make sense, an overall study that includes total equipment cost, port utilization, maintenance, and power cost over time should be undertaken—involving both facilities and networking—to make the best overall decision. On the whole, point-to-point cabling can present data center many problems. Structured cabling is a better choice over point-to-point cabling.