With the thriving 100G market, QSFP28 has become the dominant form factor for 100G networks. The QSFP28 transceiver offers four channels of high-speed differential signals with data rates ranging from 25 Gbps up to potentially 40 Gbps, and meets 100 Gbps Ethernet (4×25 Gbps) and 100 Gbps 4X InfiniBand Enhanced Data Rate (EDR) requirements. As a world leader in IT and networking, Cisco 100G transceivers have been highly favored by many Ethernet users. Cisco 100G QSFP-100G-SM-SR and Cisco QSFP-100G-CWDM4-S are two different form factors of Cisco 100G optics. This article would give brief introduction to Cisco 100G QSFP-100G-SM-SR and Cisco QSFP-100G-CWDM4-S, and further analysis QSFP-100G-SM-SR Vs QSFP-100G-CWDM4-S.

Cisco 100G QSFP-100G-SM-SR

The maximum transmission distance of the Cisco QSFP-100G-SM-SR QSFP module is kilometers via a standard pair of G.652 singlemode fiber with duplex LC connectors. The 100 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed within the device. The operating temperature range is from +10 to +60°C with an optical link budget of 4.2 decibels. This 4.2-decibel link budget offers the ability to support the loss from patch panels in the link in a data center environment. QSFP-100G-SM-SR is interoperable with QSFP-100G-CWDM4-S.

Cisco 100G QSFP-100G-CWDM4-S

As same as Cisco 100G QSFP-100G-SM-SR, Cisco 100G QSFP-100G-CWDM4-S supports link lengths of up to 2 kilometers as well. The QSFP-100G-CWDM4-S optical transceiver is for singlemode fiber. There are 4 CWDM-WDM lanes in the 12761-1331-nm wavelength window. This 100GBASE QSFP-100G-CWDM4-S Cisco 100G transceiver converts 4 input channels of 25Gb/s electrical data to 4 channels of CWDM optical signals and then multiplexes them into a single channel for 100Gb/s optical transmission. It uses a duplex LC connector on the optical interface and uses an MSA-compliant 38-pin edge type connector on electrical interface. This QSFP-100G-CWDM4-S Cisco 100G transceiver is equivalent to Cisco QSFP-100G-SM-SR.

Cisco 100G QSFP-100G-CWDM4-S


From the above descriptions, it is obvious that the Cisco QSFP-100G-SM-SR is compatible with Cisco QSFP-100G-CWDM4-S 100G optical transceivers. They are used interoperably. And thus, they have many things in common.


Multiplexing and demultiplexing of the four wavelengths are managed within both Cisco 100G QSFP-100G-SM-SR and Cisco QSFP-100G-CWDM4-S. They convert 4 input channels of 25Gb/s electrical data to 4 channels of CWDM optical signals and then multiplexes them into a single channel for 100Gb/s optical transmission.They all use a standard pair of G.652singlemode fiber.

—Transmission distance

The transmission reach of both Cisco 100G QSFP-100G-SM-SR and Cisco QSFP-100G-CWDM4-S all can be up to 2 kilometers.


The original Cisco 100G QSFP-100G-SM-SR and Cisco QSFP-100G-CWDM4-S optical module is pricey, so nowadays many enterprises and data center workers would choose to buy Cisco compatible optical modules from third party vendor. For the price of QSFP-100G-SM-SR and QSFP-100G-CWDM4-S, they are identical at fs.com. At Amazon.com, the price is much higher. You can check them by clicking the following link.

Cisco 100G QSFP-100G-SM-SR: https://www.fs.com/products/65210.html

Cisco QSFP-100G-CWDM4-S: https://www.fs.com/products/65219.html

Cisco QSFP-100G-CWDM4-S:https://www.amazon.com/Third-Party-100GBASE-CWDM4-QSFP28-Cisco/dp/B01G656GGY/ref=sr_1_1?ie=UTF8&qid=1513073676&sr=8-1&keywords=Cisco+QSFP-100G-CWDM4-S


Through this article, we are clear that the QSFP-100G-SM-SR and QSFP-100G-CWDM4-S can be used interoperably. And they are totally identical at large extent. And thus, there are basically no difference on QSFP-100G-SM-SR Vs QSFP-100G-CWDM4-S. Nowadays, they have been applied to data center, high-performance computing networks, enterprise core and distribution layers, and service provider applications.

Mikrotik Switches Vs Cisco Switches

As a worldwide leader in IT and fiber optical networking, Cisco switches play a leading role in manufacturing network switches and in providing switching solutions for data center and enterprise networks with large and medium-size forms. MikroTik, a Latvian company which was founded in 1996 to develop routers and wireless ISP systems. Their cloud switches are highly favored by many Ethernet users in recent years. And thus, people are entangled with Cisco and Mikrotik switches. This article would give brief introduction to Cisco and Mikrotik switches, and put emphasis on Mikrotik Switches Vs Cisco Switches.

Cisco Switches

According to different usage, Cisco divided their switches into the following categories: LAN Access Switches, LAN Digital Building Switches, LAN Core and Distribution Switches, Data Center Switches, Service Provider Switches, Industrial Ethernet Switches, Virtual Networking and Small Business Switches. And every category has its switching series. The Cisco Catalyst series switch delivers ease of management and configuration for small to medium-sized enterprise wiring closets in a single system, without the need for additional modules. The following list is about the Cisco Catalyst series switch.

Cisco Catalyst series switch

Mikrotik Switches

Comparing to Cisco switches, the total amount of Mikrotik switches is much smaller. According to the official website of Mikrotik, there are only twelve Mikrotik switches. Ethernet smart switches and cloud core router switches are two series switches of Mikrotik switches. The cloud core switch, or cloud router switch, abbreviated as CRS, is a highly configurable switch, powered by RouterOS. They are the new products of Mokrotik switches. For the cloud router switch, there are nine models currently available. Here lists three different cases of the cloud core switch:

  • CRS125-24G-1S-2HnD-IN (integrated wireless, indoor case)
  • CRS125-24G-1S-IN (indoor case)
  • CRS125-24G-1S-RM (rackmount case)

Mikrotik Switches Vs Cisco Switches


The CPU on both Cisco and Mikrotik switches is used for management purposes (snmp stats, cli management, etc) and it does not affect the data path. Switching is not done in CPU, neither on Cisco nor on Mikrotik. Switching is done on dedicated ASIC chips specifically designed for this job (thus giving wirespeed). So comparing the CPUs won’t mean much about forwarding performance – which is the metric you should care about.

—Power Consumption

One of big problems with Mikrotik switches is their power. The buyers would prefer to pay another couple hundred dollars to have dual power supplies that are removable. And thus, many Ethernet users cannot use Mikrotik in these cases. Comparing to Mikrotik switches, Cisco switches have less power consumption by their advanced technology.

—Network Monitoring Software Systems

Most network monitoring software systems natively understand, support and auto-detect Cisco devices and support Cisco SNMP OIDs (CPU, temp, load, bandwidth, errors, power supply status, and many other sub-system counters in a Cisco device.

When configuring your existing network monitor system(s), your network monitor system(s) may not even know what a Mikrotik is and probably does not have native built-in MIBs/OIDs used by SNMP to auto-check/monitor a network. Thus, an administrator would probably need to configure the Mikrotik graphic icons and configure all of the SNMP checks for MIBs/OIDs from/to a Mikrotik.

Mikrotik Switches Vs Cisco Switches: How to Select?

Mikrotik routers and switches are great. Most people like them and use them almost everywhere. However, because Mikrotik is still the new kid on the block when it comes to carrier-grade commercial-grade business grade high-throughput products, it may sometimes be a little difficult to find local network technicians or local phone support for Mikrotik products when adding new equipment into your network. So Cisco switch is more solid and people are more satisfied with them.

A Comprehensive Understanding of CFP Modules

As a new emerging technology, 100G is some sort of evolution and part of revolution. The new CFP (C form-factor pluggable) optics is now a revolutionary step as one form factor of 100G optic transceiver. The CFP modules offer the enabling step for cost-effective and successful 100G deployment. So what is it? And how does it work in 100G network? This article would give a comprehensive introduction to CFP modules.


CFP Wiki

Abbreviated as CFP transceiver, C Form-Factor Pluggable transceiver is a multi-sourced pluggable transceiver used in the transmission of high-speed digital signals. It is specified by a multi-source agreement (MSA) between competing manufacturers. The c stands for the Latin letter C used to express the number 100 (centum), since the standard was primarily developed for 100 Gigabit Ethernet systems. It is a hot-swappable input/output transceiver that is used in the data communication and telecommunication networks.

The CFP transceiver was designed after the small form-factor pluggable transceiver (SFP) interface, but is significantly larger to support 100 Gbit/s. While the electrical connection of a CFP transceiver uses 10 x 10 Gbit/s lanes in each direction (RX, TX) the optical connection can support both 10 x 10 Gbit/s and 4 x 25 Gbit/s variants of 100 Gbit/s interconnects (typically referred to as 100GBASE-SR10 in 100 meter MMF, 100GBASE-LR10 and 100GBASE-LR4 in 10 km SMF reach, and 100GBASE-ER10 and 100GBASE-ER4 in 40 km SMF reach respectively.)

Core Features of CFP Modules

– Support to 103 Gbps and 112 Gbps aggregate bit rates.

– Connector Interface

– Operating Case Temperature

– Diagnostic Monitoring

– RoHS6 Compliant

– Single 3.3V Supply for Power and a Power dissipation < 12W

One distinctive feature of CFP modules is that they support digital diagnostic monitoring functions or the digital optical monitoring. This is the feature that gives users the ability to monitor the real-time parameters such as the optical output power, the optical input power, the temperature, the laser bias current and the transceiver supply voltage.

Inner Structure of CFP Modules

The basic CFP modules consist of the following parts.

1. An Integrated Coherent Optics Transmitter which sends the TX optical signal.

2. An Integrated Coherent Optics Receiver which receives the RX optical signals.

3. The CFP connector

4. Coherent DSP

Most of the CFP optical transceivers adhere OIF CFP-ACO (Analog Coherent Signals) and are connectable to multiple DSP’s. The biggest engineering challenge that CFP2 faces is the adoption of the high-speed 25 Gbps electrical interface due to the reason that the CFP was based on the third generation.

It can be a multimode parallel optic transceiver module that is designed to offer high-density 100G Ethernet and Optical Transport Network (OTN). The device is designed to offer maximization of the delivery of the 10G data channels for the 100G networks that support 100 Gbps SR10 and 10 X 10 Gbps.

Development of CFP Modules

The original CFP specification was proposed at a time when 10 Gbit/s signals were far more achievable than 25 Gbit/s signals. As such to achieve 100 Gbit/s line rate, the most affordable solution was based on 10 lanes of 10 Gbit/s. However, as expected, improvements in technology has allowed higher performance and higher density. Hence the development of the CFP2 and CFP4 specifications. While electrical similar, they specify a form-factor of 1/2 and 1/4 respectively in size of the original specification. Note that CFP, CFP2 and CFP4 optical transceiver are not interchangeable (but would be inter-operable at the optical interface with appropriate connectors). The following table shows the basic parameter of CFP, CFP2 and CFP4 transceivers.

basic parameter of CFP, CFP2 and CFP4 transceivers


In this article, we mainly introduced the definition, core features, inner structure and development of CFP modules. Comparing to 100G QSFP28 transceiver, CFP price is not so competitive. But CFP optical transceiver is still the key to cost-effective and reliable 100G deployment, and it has been widely deployed in OTU4 411-9D1F, 100GBASE-LR4 Ethernet and data centers.

25G Switch Vs. 40G Switch: How to Choose?

25G Ethernet and 40G Ethernet are two “transiting” approaches for upgrading network from 10G to 100G. Some analysts believe 25G could be the second highest Ethernet server connectivity technology sold and shipped in the next five years, behind 10G. Meanwhile, a number of comments from industry experts declaring that 40G Ethernet is dead. Is that true? And how to make a right decision? This passage would give a brief introduction on 25G switch and 40G switch and put emphasis on 25G switch Vs. 40G switch.

25G Switch

25G technology is the new standard that offer significant density, cost and power benefits for server to top of rack connections. Its single higher speed 25 Gb/s lanes maximize bandwidth and switch fabric utilization. A single lane per physical port maximizes the number of connected servers or uplinks per switch. Generally, 25G switch is a 48 port switch on the 25G switch market right now. Nowadays, many major brands of switch manufactures have launched their 25G switch, such as Cisco, Juniper, Arista, Mellanox, Dell.


40G Switch

Comparing with 25G switch, 40G switch is much familiar to us. A 40G switch generally refers to the data speeds of the ports feeding into the switch. Hence, a 40G switch has 40 Gb/s ports. The overall switching capacity of the 40G switch will be much higher depending on the total number of ports and the power of the switching fabric itself. According to Infonetics Research in early 2015, 40Gb Ethernet switch has been popular in the data center market while 100G switch is more popular with service providers. And thus, 40G Ethernet and 40G switch are not so dead like being mentioned in the fast paragraph.

FS S8050-20Q4C 40G switch

25G switch Vs. 40G switch

—Switch Compatibility

Relatively speaking, 25G switch is less common on the market. In terms of 25G switch compatibility, that is depending the switch supplier. Just take Arista 25G switch for an example, the majority of their 25G switches and Network Interface cards offer backward compatibility to 10G, there is the flexibility to manage a gradual migration to higher speed servers and mix and match port speeds. All SFP based 25G ports on Arista switches and 25G NICs from Cavium can be used at 10G speed. The compatibility of 40G switch also depends on the switch brands. But as a new emerging technology, 25G switch has higher compatibility than 40G switch.

—Port and system density

High performance 25GbE chips use single-lane 25G serializer-deserializer (Serdes) technology similar in operation to 10GbE but delivering 2.5 times the performance, thus reducing the power and cost per gigabit significantly. 25G provides higher port and system density than a comparable 40G solution. Both power savings and higher density results in lower cooling requirements and operational expenditure for data center operators.

—Connection Option

Switch-to-server or switch-to-switch (or switch-to-blade switch) are two connection options for 25G switch connection. Right now, network vendors are positioning 25G only for switch-to-server. Until now, no network vendor advertising 25G for switch-to-switch—Cisco doesn’t even offer a 25G fiber transceiver, and HPE has priced theirs higher than 40G and 100G transceivers. In other words, no one is talking about 25G for switch-to-switch links right now. We shall see this in 2018.


25G twinax works best within a single rack with a top-of-rack switch and 1 and 2 meter cables. 25G with 3+ meter cables requires forward error correction (FEC), which adds ~250ns of one-way latency and may introduce vendor interop issues. If you’re adopting 25G, plan to densely pack compute into 10kVA–12kVA racks. 40G DAC cable is more expensive than 25G DAC cable based on the identical cable length.

25G Switch Vs. 40G Switch: How to Choose?

Through the above description and comparison, we are cleared about some pros and cons of 25Gb Ethernet switch and 40Gb Ethernet switch as well as 25G switch Vs. 40G. As for how to choose the best one, that depends on your demand and usage environment. 25G switch uses less power and produce less heat than 40G, but it is limited at 25G distance. For data center network connectivity, 100G switch is more of a smart choice than 25G switch and 40G switch. In campus and access networks with their long fiber runs and low bandwidth needs, 40G switch is more worthy to buy. So far it seems that 25G switch is not a cost-effective solution.

100G CFP to QSFP28 Adapter Converter Module Datasheet

With the explosive growth in mobile data traffic, data centers, and cloud services, people’s call for 100G Ethernet is more higher than ever before. To build and support the 100G Ethernet, a variety of technologies and devices are needed. 100G CFP modules, QSFP28 modules and 100G CFP to QSFP28 adapter converter module are of necessity. This article would put emphasis on introducing four 100G CFP to QSFP28 adapter converter modules and their applications.

Overview on 100G CFP to QSFP28 Converter Module

The 100G CFP to QSFP28 adapter converter module is a high performance, hot pluggable, and interconnect solution supporting 100G Ethernet and Telecom. The converter module converts a CFP MSA interface to 1-port of 100GE QSFP28. It is compliant with the CFP MSA. The converter module supports FEC (Forward Error Correction) function; the user can enable the FEC function through the register configuration.

100G CFP to QSFP28 Converter Module

100G CFP to QSFP28 adapter converter module converts 10 bidirectional 10G channels to 4 bidirectional 25G channels operating at up to 28Gbps per channel. By plugging 100G QSFP28 transceiver into the QSFP28 connector on the 100G CFP to QSFP28 adapter converter module, CFP module and QSFP28 module are interconnected. The 100G CFP to QSFP28 converter module datasheet is shown as below:

100G CFP to QSFP28 Converter Module

Cisco 100G CFP to QSFP28 Converter Module

Cisco CVR-CFP-100G supports modules with a 4x25G electrical interface. The CVR-CFP-100G supports modules with a 10x10G electrical interface such as 100G CFP. The CVR-CFP-100G CFP to QSFP28 converter module supports the two aggregate data rates of 100Gbps Ethernet and Optical Transport Network (OTN) rates. The CVR-CFP-100G CFP to QSFP28 converter module supports only the 100GBase Ethernet data rate. The Cisco CVR-CFP-100G CFP to QSFP28 converter module datasheet is shown as below:

Cisco 100G CFP to QSFP28 Converter Module

100G CFP2 to QSFP28 Converter Module

Like being mentioned 100G CFP to QSFP28 adapter converter module, 100G CFP2 to QSFP28 converter module converts 10 bidirectional 10G channels to 4 bidirectional 25G channels operating at up to 28Gbps per channel. By plugging 100G QSFP28 transceiver into the QSFP28 connector on the 100G CFP2 to QSFP28 adapter converter module, 100G QSFP28 transceiver is in the CFP2 port of your device. In this way, power consumes less than using an equivalent CFP2. The 100G CFP2 to QSFP28 converter module datasheet is shown as below:

100G CFP2 to QSFP28 Converter Module

Cisco 100G CFP2 to QSFP28 Converter Module

The Cisco CVR-CFP2-100G adapter converter module allows a Cisco 100G QSFP28 transceiver module to be plugged into a CFP2 port and to emulate an optical CFP2 100G Module. The Cisco CVR-CFP2-100G CFP2 to QSFP28 converter module datasheet is shown as below:

Cisco 100G CFP2 to QSFP28 Converter Module


This article mainly introduced four types of 100G CFP to QSFP28 converter module, the principles of converting, as well as the method of usage. The price of 100G CFP to QSFP28 converter module is just a little bit higher than CFP price. But the CFP to QSFP28 converter module has lower power consumption than CFP. Thus, the 100G CFP to QSFP28 converter is more cost-effective. Nowadays, the 100G CFP to QSFP28 converter modules have been widely deployed to high-speed core router connections, datacom/telecom switch, data aggregation and backplane applications, and proprietary protocol and density application.

How to Select The Perfect Fiber Jumper Cables?

Fiber jumper cables are mainly used for connection in the context of optical fiber communications including applications like cable TV (CATV), inside buildings and in fiber to the home (FTTH) installations. Nowadays, optical fiber jumpers are varied in cables and connector types. It is hard to determine the differences between one fiber optic cable jumper and another. This article would put emphasis on guiding you to select the perfect fiber jumper cables from the following six perspectives.


Cable Type of Fiber Jumper Cables

Fiber jumper cables comes in two general types, singlemode and multimode optical fiber jumper. They are different in fiber diameter, classifications of fiber strands, jacket color, transmission speed and etc.

Singlemode fiber jumper cable generally has a 9 micron diameter glass fiber. There are two sub groups (referred to as OS1 and OS2) but most cable is “dual rated” to cover both classifications. Multimode optical fiber jumper can have several different diameters and classifications of fiber strands. The two diameters currently in use are 62.5 Micron and 50 Micron. Within the 50 Micron diameter multimode cable, there are three different grades (referred to as OM2, OM3, and OM4). The cable types used in the patch cord should match that of the network cabling to which they are attached via the patch panel.

Jacket Diameters

The fiber optic cable jumpers may be available in different “jacket diameters” (such as 2mm or 3mm). Thinner diameters (1.6 or 2mm) may be preferable in dense installation within a single rack since they take up less space and are more flexible. Fiber optic cable jumpers that route from rack to rack (especially via cable tray) may be more suitable if they have the thicker jacket that results in larger diameters thus making them more rigid.

Jacket Material

Flammability of the jacket material could become an issue if the area they are in has special requirements for flame spread or products of combustion in case of a fire. In these cases, optical jumpers may have to be classified as “Plenum Rated” (OFNP) rather than “Riser Rated” (OFNR).

Connector Type

See the connector type descriptions below. Some fiber jumper cables may have different connector types on each end to accommodate interconnection of devices with dissimilar connectors. In some cases, there may be a connector on only one end, and bare or unterminated fiber on the other. These are usually referred to as “pigtails” rather than “patch Cords”.


Simplex or Duplex

Unlike copper patch cords which send information in both directions (having multiple pairs of conductors with which to do so), most fiber jumper cables have a single strand of fiber allowing for signal flow in one direction only.

Connecting equipment so that it can send and receive information requires two strands of fiber (one to transmit and one to receive information). This can be accommodated by using two “simplex” (single strand of fiber) cables for each equipment interconnection or a “duplex” cable, with conductors and/or connectors bonded together in pairs.


Overall length of the fiber jumper cables may be specified in feet or meters, depending on your preference.


In this article, we mainly introduce six factors attaching to the fiber jumper cables—cable type, jacket diameters, jacket material, connector type, type of communication service as well as the length. You can select the proper patch cord you need through considering those six attributes. Hope this post is helpful for you to fully understand optical fiber jumper.

A Glimpse Into The Future: 25G & 50G Ethernet

With the ever growing usage of 10G network, 10G could not satisfy the requirement for some Ethernet network users who urge for a higher demand on speed, distance, media and cost. Under this circumstance, upgrading network is paramount. For 100G network upgrading, there are three available approaches, “10G—40G—100G”, “10G—25G—100G” or “10G—25G—50G—100G”. The latter two are announced to better satisfy the data center and cloud network. Comparing to 40G and 100G, people heard less about 25G and 50G. So what are they? This article would put emphasis on 25G Ethernet and 50G Ethernet as well as their optics.

25G-100G immigration

25G Ethernet

25 Gigabit Ethernet, abbreviating as 25G Ethernet, is standard for Ethernet network connectivity. Developed by IEEE P802.3by 25 Gb/s Ethernet Task Force, 25G Ethernet is a standard for Ethernet connectivity. The 25 Gigabit Ethernet Consortium is an open organization to all third parties who wish to participate as members to enable the transmission of Ethernet frames at 25 or 50 Gigabit per second (Gbps) and to promote the standardization and improvement of the interfaces for applicable products. The main features of 25G Ethernet are listed in the following:

  • A single lane per physical port maximizes the number of connected servers or uplinks per switch.
  • Single higher speed 25 Gb/s lanes maximize bandwidth and switch fabric utilization vs. 4 x 10 Gb/s lanes.
  • Overall higher port count, utilization and total server interconnect bandwidth vs. 40 GE.
  • Connections to switch ASICs is limited by SERDES count and bandwidth.

SFP28 Pluggable Modules

SFP28 is the abbreviation of Small Form-Factor Pluggable 28, which is the third generation of SFP interconnect systems. The SFP28 optical module is designed for 25G performance and developed by the IEEE 802.3by specification. According to the SFP28 Multi-Source Agreement (MSA) and SFP28 specification, the SFP28 is designed with a form factor, optical/electrical connection and digital diagnostic interface. In addition, the SFP28 optical transceiver has also been designed to meet the harshest external operating conditions including temperature, humidity and EMI interference. Below are the industry standard 25G optics:

industry standard 25G optics

50G Ethernet

Comparing to 40G Ethernet, 50G Ethernet is more rarely known by people. Being led by the 25G Ethernet Consortium, 50G Ethernet is initially based on 2 lanes of 25 Gb/s. IEEE802.3bs is the 50G per lane specifications to support Nx50G configurations. And the standard expected in September 2018 while the interface expected on the market in 2018+. Different from 40G Ethernet, 50G initial limited deployment as proprietary 2x25G. In terms of technology, 40G and 50G per lane (Serial) technology will be defined together (40G as reduced speed 50G). With the respect of cost, 40G and 50G Serial will have similar cost, i.e. 50G Serial will offer 25% more bandwidth for the same cost. The core features of 50G Ethernet are listed in the below:

  • A faster base signaling rate is needed to for higher capacity.
  • Similar to 25 GE, 50 GE extends existing common network topology for higher speed.
  • The server and data center market requirements vary widely.

50G Pluggable Modules

New 50 GE pluggable modules are in the same common form factor sizes as other common pluggable modules. There are two form factors of 50G modules, SFP56 and QSFP56. The SFP56 pluggable module has the same size as SFP, SFP+ and SFP28 while the QSFP56 pluggable module has the same size as QSFP, QSFP+ and QSFP28.


Through this article, we are cleared the 25G and 50G Ethernet as well as their optics respectively. With the ever increasing usage of network data due to millions of new connected devices to servers and storages data centers, 25G Ethernet and 50G Ethernet provide a flexibility, scalibilty, cost-efficient way for adapting to future network growth.

How to Select Fiber Optic Cables of High Quality?

With the growing numbers of fiber optic patch cord manufacturers, it is difficult to distinguish the quality of fiber optic cables. Poor fiber jumpers could result in many adverse consequences, such as data loss, signal delay and etc. When selecting fiber optic cables, you should pay much attention to the trap of the low price so as to avoid picking up production made by recovered materials. In this article, we would introduce some detailed process to guide you to make right decision for selecting decent fiber optic cables.

About Fiber Optic Cable

Fiber optic cable, also called fiber optic jumper or fiber optic patch cord, is a length of fiber cabling fitted with LC, SC, FC, E2000, DIN, MTRJ or ST connectors at each end. Ferrule is paramount to fiber, which is a ring or cap attached to an object to protect against damage, splitting, or wear. As an essential component in fiber optic, it is used to align and protect the stripped end of a fiber.

fiber optic cable

Manufacturing Process of Fiber Optic Cable

Place of origin attaches great importance to any products, so does the fiber optic cable. Besides the origin, method of manufacture also matters. The production process of fiber optic patch codes is very complicated unless you master it very well. Following is the production process of fiber optic patch cords.

Step1: Pretreatment of fiber optic. Peel fibers by using technical instrument, the main propose of it is to peel the fiber jacket.

Step2: Installment of Fiber ferrule. Fiber ferrule is an important part of fiber optic patch cables, so when installing fiber ferrule, the quality of it should be concerned.

Step3: Preparation of grouting glue.Get the glue ready since fiber stub need to be grouted later. Gel injection of fiber ferrule. The standard of a good gel injection is that a little glue can be seen at the front end of fiber ferrule.

Step4: Solidification of colloid. Insert the fiber into fiber ferrule which has been injected gel, and then put it in curing oven to be solidified. Usually, the temperature of solidification is 80 to 90 degree.

As being mentioned, fiber ferrule is a vital part in fiber optic cable, which is used together with the connector that connects the fiber cable either to another cable or to a transmitter or receiver. The ferrule keeps the fibers accurately aligned within the connector. And thus, the quality of fiber jumpers depends on the quality of fiber ferrule in a large extent. However, in order to achieve more benefits, many manufacturers buy in inferior fiber ferrule or reuse fiber ferrule. As a result, the fiber optic patch cables they made are of poor quality. So it is not a good way to buy cheap jumpers without putting the fiber optic patch cord manufacturers into consideration.



So how to choose a decent fiber optic patch cord manufacturer? Here are some indispensable and refined characteristics of reliable fiber optic cable suppliers: have a good sense of service, treat customers as friends, provide reasonable price but not the cheapest, have a sense of service, and also conscientious, instead of those sell their products randomly just concerning about their performance and benefits.

10G Technology: 10GBASE-T Vs. SFP+

As the basis of upgrading network, 10G network has been ubiquitous in data center, enterprise network and even home networking. 10GBASE-T and 10G SFP+ are two different kinds of technology which transmit data via copper and fiber respectively. 10GBASE-T technology provides the most flexible and economical solution while 10G SFP+ offers the compatible and user-friendly solution for 10G Ethernet connectivity option. This article would shed light on the difference between 10GBASE-T and 10G SFP+.

10GBASE-T Technology

As the fourth generation of IEEE standardized Base-T technologies, 10GBASE-T is designed to reduce overall costs and improve flexibility. By using RJ45 connectors and unshielded twisted pair cabling, 10GBASE-T allows 10Mbps, 100Mbps, 1Gbps, and 10Gbps data transmission, while being backward-compatible with prior generations. Merits and demerits of using 10GBASE-T are listed in the below.

Pros of 10GBASE-T
  • Cheap twisted pair cables.
  • Patch panels can be used without messing around with transceivers.
Cons of 10GBASE-T
  • Higher power consumption.
  • People may get tempted to use substandard cabling, and this would have a negative influence on the speed.
  • No good way to extend length beyond 100m (though this can be somewhat mitigated by choosing switches with mostly 10GBASE-T but also a handful of SFP+ ports) limited choice of equipment.
10G SFP+ Technology

The 10G SFP+ transceiver meets the standard of Multi-Sourcing Agreement (MSA), and provides the cost effective solution for 10G optical data communication. It supports both duplex and simplex LC optics interfaces. The 10G SFP+ transceiver consists of 10Gbit/s DFB/EML optical transmitter and PIN receiver, which allow 300m~120km 10G Ethernet and 10G fiber channel applications. Advantages and disadvantages of using 10G SFP+ transceivers are listed in the below.

Pros of SFP+
  • Lower latency
  • Lower power consumption
  • Cheaper NICs and switches
  • More choice of connected equipment.
  • With transceivers and fiber basically any run length can be covered.
Cons of SFP+
  • Apparently, it is not a big deal for transmission within short distance.
  • For longer runs or runs that need to go through patch panels needs transceivers and fiber. Fiber itself is cheap but transceivers, termination, patch panels, and etc for fiber would cost a lot.

This passage would mainly demonstrate the difference between 10GbE base T and SFP+ options from the respective of technology, latency, and power consumption.


Generally, 10GBase-T is cheaper and easier to deploy than the alternative SFP+ technologies. You can further compare these two different technologies in the following table:

Table1 Comparison between 10GBASE T and SFP Plus


Low latency is paramount to ensure fast response time and reduce CPU idle cycles. That increases data center efficiency and ROI. With the increasing of using private cloud applications, the need for low latency is growing fast in large scale data centers.

When it comes to 10GBase-T, the PHY standard uses block encoding to transport data across the cable without errors. The standard specifies 2.6 microseconds for the transmit-receive pair, and the size of the block requires that latency to be less that 2 microseconds. SFP+ uses simplified electronics without encoding, and typical latency is around 300 nanoseconds (ns) per link. You can further compare them in the below table.

latency comparison

Basically, there are only slight differences between 10GBASE-T and SFP+ in terms of application latency. Relatively speaking, 10G SFP+ has lower latency than 10GBASE-T. High latency would exert negative influence on CPU and therefore limiting data center efficiency and increasing operational costs.

—Power Consumption

10GBase-T components today require anywhere from 2 to 5 watts per port at each end of the cable (depending on the distance of the cable) while SFP+ requires approximately 0.7 watt (regardless of distance). The difference is clearly shown in the below chart.

power consumption comparison

(Resource: http://www.datacenterknowledge.com)


Through this article, we are clear about the pros and cons of 10GBASE-T and SFP+ as well as their differences in technology, application latency and power consumption. It is evident that SFP+ is the right technology to ensure optimal performance with lowest latency and lower power usage in the data center. The cost saving becomes obvious when deploying from 1000 to 10,000 cables in the data center.

Stacking Vs. Chassis Switch: How to Choose?

Maximizing scalability and optimizing performance are two paramount factors when you design or upgrade your network. It is hard to find the right balance. Given that you need more than 48 ports in a wiring closet, but you could not decide which type of switches to buy. Stacking switch or non-stacking switch? Or does a modular chassis solution make more sense? In this article, we would make a comparison between stacking and chassis access switches and guide you to make an appropriate decision.

Stacking Switches Solutions

Over the years, stacking network switches have been highly favored by lots of Ethernet users and been a core component of an enterprise-grade switch. So what is reason for the popularity of stacking switches? By using stacking switches, we can add ports as we need them by simply purchasing another switch and adding it to the stack. We can stack up to nine Cisco 3750-X switches and have 432 x 10/100/1000 ports and 18 x 10 Gbps ports. We can do this using only 9RU’s of rack space. A chassis would require over double the rack space to achieve this access port density. This makes these switches very popular as top-of-rack switches in the data center.


Figure1: Brocade Stackable Switches (Resource: www.Brocade.com)

Pros of Stacking Switches
  • Pay-as-you-grow
  • Small Physical Footprint
  • Convenient 100v Power Standard
  • Virtual Chassis Capability
  • Cross-Stack EtherChannel
Cons of Stacking Switches
  • Management Difficulties
  • Power Demands
  • Software Complexity
  • Instability
Chassis Switches Solutions

Chassis devices, often being “premier” devices, may offer software and/or hardware features unavailable on a stack. They are the flagship models of every vendor’s switching line. In contrast to the fixed configuration switches, it is engineered to operate as single integrated system. Configuring high availability is simple and it works every single time. A failed line card will not bring down the entire chassis. Additionally, a chassis will drive consistency in deployment.

Cisco Chassis Switches

Figure2: Cisco Chassis Switches (Resource: www.Cisco.com)

Pros of Stacking Switches
  • Solid High Availability Features
  • Modular Design
  • Supports Wide Range of Line Cards
  • Simple to Deploy
Cons of Stacking Switches
  • Physical Space (twice the space of stacks)
  • Expensive Power Supplies
  • 220v Power for PoE Solutions
How to Choose?

Just as the same as the every comparison on the similar kits, the decision really depends on your actual requirements. Once we have this, finding the right hardware is very straightforward. It is important to balance the cost of acquisition versus the cost of operations and impact to the business due to outages. And that is what we always thinking about when we make a decision.

In this article, we mainly provide the detailed information about stacking and chassis switches solutions, and offer you relatively enough information to help you to make a decision on choosing the best switching solutions for setting up or upgrading your network. There are too many variables to give a one-size-fits-all recommendation, but in general chassis Ethernet switches‘ solutions are our preference. In addition, you should keep in mind that pricing should not be the focused too much. We can get both designs for a pretty reasonable price, regardless of requirements. If your network can benefit from both stackables and chassis, the chassis solution would be a good choice.

Cloud Core Switch—An Economic Choice for L3 Switch

MikroTik Switches have been popularly received favorable reviews, and this is inseparable with their keeping on the bleeding edge of switching technology. As a new member of MikroTik Smart Switch series, cloud core switch, also called cloud router switch, combing the best features of a fully functional router and a Layer 3 switch. That is to say, this cloud router switch works as both switch and router to connect the VLAN. This article would mainly discuss about cloud core switch, CRS226-24G-2S+RM switch and its connectivity solutions, as well as the reasons why they are economic choice for L3 switch.

About Cloud Core Switch

The cloud core switch, or cloud router switch, abbreviated as CRS, is a highly configurable switch, powered by RouterOS. It has 24 Gigabit Ethernet port. The Ethernet port 2-24 are switched, and the device can be accessed via these ports through the IP Ethernet port 1 is configured as a DHCP client and has firewall on it. The SFP port is configured the same way as Ethernet 1, with a firewall and DHCP client on it. For the cloud router switch, there are nine models currently available. Here lists three different cases of the cloud core switch:

  • CRS125-24G-1S-2HnD-IN (integrated wireless, indoor case)
  • CRS125-24G-1S-IN (indoor case)
  • CRS125-24G-1S-RM (rackmount case)

MikroTik cloud router switch

Figure1: MikroTik cloud router switches(Resource: www.MikroTik.com)

Cloud Core Switch CRS226-24G-2S+RM

As one of the cloud core switches, CRS226-24G-2S+RM have been highly favored by most people. CRS226-24G-2S+RM is a fully functional layer 3 cloud router switch powered by Router OS, which is also available in 1U rackmount case. It comes with a special switch menu which includes all the specific configuration options for switches. It has 24 Gigabit ports and two SFP+ cages for 10G connectivity in which first SFP port supports 1.25G/10G modules and second port only 10G modules. Ports can be removed from the switch configuration and used for routing purposes if needed. The most distinctive feature of CRS226-24G-2S+RM is that uses a new class of switch chips, which allows us to have two SFP+ ports for 10G connectivity. The main features of this cloud core switch are listed in the following:

  • Fully manageable L3 switch, full wire speed switching
  • Configure ports as switch, or for routing
  • If required, full RouterOS power right there
  • SFP+ ports for 10G connectivity


Figure2: cloud core switch CRS226-24G-2S+RM(Resource: www.MikroTik.com)

Connectivity Solutions for CRS226-24G-2S+RM

As being mentioned, the cloud core switch CRS226-24G-2S+RM has 24 Gigabit ports and 2 SFP+ ports. For the twenty-four 10/100/1000 Ethernet ports, you could use both network cables and optical transceivers to connect. The transmission speed of Cat5 and Cat5e cables can be up to 100 Mb/s and 1G respectively. Besides, you can also use 10/100/1000BASE-T copper transceiver to make network connectivity. But it costs more than the network cables. In terms of 10G SFP+ ports, there are also two connectivity approaches. You can use both 10G SFP+ modules and 10G SFP+ DAC copper cable to connect. Relatively speaking, the 10G DAC cable is cheaper a lot than the 10G transceiver. But if transmission quality is your pursuit, and then 10GBASE SFP+ transceivers would be a good choice.

Why Are Cloud Core Switches Economic Choice for L3 Switch?

According to the above description, cloud core switches are powered by Router OS. RouterOS lets you add upper layer functionality. The cloud core switch is very far below wire speed when doing layer 3 or above. In fact, the cloud core switch is more of a bare-bones layer 2 switch that has an embedded low-horsepower router. In short, the switch features are useful for making bridges that work at wire speed, but they’re limited to simple forwarding and vlan handling. The bridge feature lets you glue almost anything together, and gives lots of filtering/manipulation tools, but it cannot perform at wire speed because it uses the main CPU. Last but not least, the average prices of Mikro Tik cloud core switches are not more than $150, you can check them by this link.


Cloud core/router Switch is a managed switch that runs RouterOS and SwitchOS, which delivers a high performance as a Layer 3 switch. They allow to manage port-to-port forwarding, apply MAC filter, configure VLANs, mirror traffic, apply bandwidth limitation and even adjust some MAC and IP header fields. The economic L3 switch including several switch models covering wide range applications, like enterprise network and home network.

Single Switch Vs. Multiple Switch: How to Select for Home Network?

Network switches are indispensable part on setting up a home network. For home Gigabit Ethernet switches, both one large single switch and multiple smaller switches are good options. Using one large switch, the speed of data transferring could be faster but the problem is you have to run multiple lines throughout the house. Using multiple switches at home maybe redundant at some extent. So how to choose?

For choosing single large switch or multiple smaller switch applied to home network, it is not an easy question to answer. Because it involves various factors—size of the house, power consumption, fiber or copper, rack mount or not. Besides, you still need to consider how dense each part of the house will have networking. And then, in terms of this topic, we did some researches on some professional forums to investigate and congregate thoughts. Most of them prefer to use one larger switch rather than multiple smaller switches for home networking. The reasons are described in the following part.

switch stacking

Figure1: multiple smaller switch stack

By using a central switch you will have UPS protection, unless you have an UPS at each location of course. And using a larger switch instead of multiple smaller ones, just because you will end up using less power that way. By using multiple switches, just make sure you buy two in case of hardware failure, that is the downside of centralizing everything to one device. So in that way, you will cost more to make sure the work of the hardware. In the below statement, we would list some merits and demerits to further clarify the reason why it is better to choose one large single switch instead of multiple smaller switches for home network.

Benefits of Using A Single Switch
  • A single switch will give you more security and better manageability, since it is centrally located.
  • In case of a small building, it is feasible to have a single optical switch catering to everyone. But if the building is big, then due to distance limitation of fast Ethernet, it may not be possible for one switch to cater to all the users. In this case, you will have to go for multiple switch solution.
  • One single switch will give you better performance than many switches. This is because in case of many switches, the inter-switch link is usually fast Ethernet or Gigabit Ethernet, but when you are using a single switch, switch backbone operates at much higher speeds.

So we can infer that if you have a small network, then you can start with single switch, and then as the network grows, you can migrate to multiple switch scenario. But if you are planning for a single switch situation, please think about a backup for this switch (either automatic failover or manual failover), so that in case of failure you can switch to the backup.

Weakness of Using Multiple Switches

First of all, using multiple switches dispatched in the different places is some sort of complexity. You need to connect all of them through some paths. And then, power consumption is also a big trouble. Using multiple switches inevitably brought much more power consumption than single switches. Besides, using multiple or redundant switch is common for security specially IP camera. If one of the switch breaks, then your other camera is still accessible. Then you have the distance limitation, which if this is the case, then you don’t have a choice but to implement more switch.


Figure2: fabric of multiple switches


According to the above description and analysis, we can draw a conclusion that using a single large network switches are better than using multiple smaller switches for home networking in most cases. But if you own an extremely larger house to meet your network requirement, and then multiple smaller switches would be good options.

Dell Powerconnect 2700 Vs. 2800 Series Switches

Both the Dell PowerConnect 2700 series and 2800 series switches are secure, fixed-port Gigabit switches. The Dell PowerConnect 2700 series was launched in the early 2000s, designed to deliver full wire-speed switching performance. Not long after the 2700 series, the 2800 series were released to support jumbo frames for networks that need to move large files across the network. They are both cost-effective solutions for small network environments, such as branch offices, schools and etc. However, it seems that it is hard to make a decision about purchasing these two series switches. This article would offer a satisfied solution to you and give a brief introduction to 2700 series and 2800 series switches.

Dell PowerConnect 2700 Series Switches

The Dell PowerConnect 2700 series switches are web-managed switches, the web-interface allows the user to easily manage the switch without learning CLI commands or integrating the switch into an SNMP-based application. These switches offer three port densities, including 8, 16, 24 and 48 Gigabit Ethernet 1 ports. Besides, the 2724 and 2748 have SFP slots in a combo port arrangement that deliver fiber capabilities. Auto MDI/MDIX and autonegotiation of speed, duplex mode and flow help deliver improved control over your network traffic. Totally, there are four models of 2700 series switch—Dell PowerConnect 2708, 2716, 2724, 2748. The main features of these switches are listed in the below:

  • There switches are prepared in advance for any elevated IT requirements.
  • They could eliminate the potential risks within the switch.
  • The 2700 series switches provide the flexibility to meet the requirement of various end users and applications environments.
  • They provide smartly balancing quality and the best prices.


Figure1: Dell Powerconnect 2716 switch(Resource: www.DELL.com)

Dell PowerConnect 2800 Series Switches

As same as the 2700 Series Switch, Dell PowerConnect 2800 Series Switches are also web-managed Gigabit Ethernet switches. These switches offer four port densities, including 8, 16 , 24, and 48 port Gigabit Ethernet ports. In addition, the 2824 and 2848 have SFP slots in a combo port arrangement that deliver fiber capabilities (SFP transceivers optional). The PowerConnect 2800 family also supports jumbo frames for networks that need to move large files across the network. There are also four switch models of 2800 series switches—Dell PowerConnect 2808, 2816, 2824, and 2848. Main benefits of 2800 series switches are listed in the following.

  • Easy web access to the managed features provides a secure environment by offering password restricted access.
  • These switches offer enhanced security by allowing the user to specify which IP addresses have access to the switch.
  • The 2800 series switches support up to six link aggregation groups consisting of up to four ports per group.
  • Advanced cable diagnostics help improve network troubleshooting.

Dell 2800 series switch

Figure2: Dell 2800 Series Switches(Resource: www.DELL.com)

Dell 2700 Vs. 2800 Series switches

As being described, the Dell PowerConnect 2700 and 2800 series switches are nearly identical. But they still have some subtle differences in STP, management configuration, switching and price.

—Spanning Tree Protocol (STP)

Compared to Dell PowerConnect 2700 series switches, 2800 series support more STP protocols and support 9000 jumbo frames (not not 9014, etc.). If you do a ping -f on the 2724 with jumbo frames enabled it will go to 5000, 5500, 6000, but not 9000 – they get fragmented at that point. Granted that is only useful for iSCSI traffic, and even then it’s not 100% necessary. And the 9014+ jumbo frames is of the preference.

—Management Configuration

Both 2700 and 2800 series switches are small office switches with minimal management. They all not have LACP. BootP/DHCP IP address management or Static IP address assignment are set within the 2800 series switches. The 2800 series switches have CLI and SNMP Command Subset while the 2700 series switches do not.


The link aggregation of both two series switches are up to eight aggregated links and up to eight member ports per aggregated link (IEEE 802.3ad). But the Jumbo frame of 2700 series switches support up to 9000 Bytes (2716, 2724, and 2748). The 2800 series switches have LACP support (IEEE 802.3ad).


Compared to 2700 series switches, 2800 series switches are cheaper. Just take the same 16-port switch for a example, a new Dell 2816 switch only needs $56 while a new Dell 2716 switch costs $112 on eBay.


Through this article, we are clear about the Dell 2700 and 2800 series Gigabit Ethernet switches as well as their differences in STP, management configuration, switching and price. They all powerful switches with outstanding cost and power savings. You can select an appropriate one according to your need.


Nowadays, the demand for high bandwidth increases and footprints for data center expands dramatically, which makes the migration from 10G to 40G much more necessary than ever before. Under this condition, many enterprises are ongoing or imminent to upgrade their data center network infrastructures. To better cater for our users, two transceivers 40G UNIV and 40G SWDM4 QSFP using SWDM (Short Wavelength Division Multiplexing) technology are compared in the following text, which intends to offer a cost effective transceiver solution for 10G to 40G migration applications. As parallel multimode MPO fiber cabling is much more expensive than Duplex-LC fiber cabling, Duplex-LC fiber patch cords will be used in these two SWDM applications, as a cost saving cabling method.

40G Direct Port-to-Port Connection

QSFP 40G UNIV Transceiver for SWDM Application

QSFP 40G UNIV is a kind of pluggable optical transceiver that fitted with Duplex-LC connector and can work with both single-mode and multimode fiber patch cable, originally released by Arista. Hence, it is also referred to as 40G SMF&MMF transceiver or 40G QSFP universal transceiver. When working with singlemode fiber, the Arista QSFP 40G UNIV can support 40G connection with a reach of 500m; and over OM3/OM4, the transmission distance can be up to 150m. Furthermore, the Arista QSFP 40G UNIV is designed with four 10G channels for transmitting and receiving four individual 10G signals through a single Duplex-LC fiber patch cord, for achieving a total 40G connection, as shown in the following figure.

Arista QSFP 40G UNIV

How does the Arista QSFP 40G UNIV work for 40G connection? The answer is SWDM technology. With the help of SWDM, Arista QSFP 40G UNIV will multiplex four wavelengths 1270nm, 1290nm, 1310nm and 1330nm to transmit four 10G signals over the single Duplex-LC fiber patch cord. And when the aggregate 40G signal passes through the receiver end, it will be demultiplexed into four individual 10G signals again. As a result, an aggregate 40G signal can be transmitted through a single Duplex-LC fiber patch cord. In short, Arista 40G universal transceiver is a very good choice for 40G migration which can work with LC-duplex single-mode or multimode fiber, instead of high-cost parallel multimode MPO fiber cabling.

QSFP 40G SWDM4 Transceiver for SWDM Application

QSFP 40G SWDM4 is an updated optical transceiver that basically works with Duplex-LC fiber patch cord for short 40G fiber link. It has the same working principle that uses SWDM technology as the QSFP 40G UNIV one, but can perform better. How does it do this? Unlike QSFP 40G UNIV working with both single-mode and multimode fiber, the QSFP 40G SWDM4 is designed to work with multimode fiber, which can transmit a multiplexed 40G signal over wide band OM5 at lengths up to 440m. It can also work in multimode fiber OM3 and OM4 with a reach of 240m and 350m, separately. What’s more, the power dissipation of QSFP 40G SWDM4 can be as low as 1.5W* since SWDM technology can match 4x WDM optical architecture with 4x electrical interface.

Similar to the QSFP 40G UNIV transceiver, four different wavelengths, 850nm, 880nm, 910nm and 940nm are used in the QSFP 40G SWDM4 transceiver. To transmit a total 40G signal, these four wavelengths will be multiplexed to carry four individual 10G signals, be transmitted through the Duplex-LC multimode fiber patch cord and finally demultiplexed. To better understand the principle of QSFP 40G SWDM4 transceiver, you can learn the above figure that illustrates how does the QSFP 40G SWDM4 work for a short distance 40G fiber link.

40G SWDM4 Transceivers

QSFP-40G-UNIV vs QSFP-40G-SWDM4, Which One is Better?

After discussion, we can learn that both QSFP 40G UNIV and QSFP 40G SWDM4 transceivers enable network operators to grow the capacity of their networks without laying new fiber cabling. In view of the transmission distance, QSFP 40G SWDM4 transceiver working with OM5 supports a longer 40G fiber link than QSFP 40G UNIV with OM3/OM4, but a shorter 40G fiber link than QSFP 40G UNIV with single mode fiber cable. When taking fiber cabling infrastructure cost into consideration, OM5 cabling costs about 50% more than OM4 and singlemode fiber is also very expensive. Then which one should be selected? Just depending on your network needs, such as the fiber link distance, the budget, etc. To better know the differences between QSFP 40G UNIV and QSFP 40G SWDM4 transceivers, here offers a table that shows their detailed parameters.


A Brief Overview of Fiber Optic Cable


A fiber optic cable, also known as optical fiber cable, is a network cable that contains two or more glass or plastic fiber cores located within a protective coating and covered with a plastic PVC outer sleeve. It’s correlated with transmission of information as light pulses along a glass or plastic strand or fiber. It’s designed for long distance, very high performance data networking and telecommunications. It has many advantages in optical fiber communication, such as large capacity, long relay distance, good security, free from electromagnetic interference and copper saving.

fiber- optic- cable

Types of Fiber Optic Cables

According to the transmission mode of light in optical fiber, fiber optic cable can be divided into single-mode fiber (SMF) and multimode fiber (MMF). Although they all belong to optical cables and aim at transmitting information, they still have some slight differences.


Single-Mode Fiber

Literally, Single-mode fiber is a single stand of glass fiber with a diameter of 8.3 to 10 microns that has one mode of transmission. Due to its smaller diameter, single-mode fiber is used for long-distance signal transmission, which minimizes the reduction in signal strength. Single-mode fiber also has a considerably higher bandwidth than multimode fiber. The light source used for single-mode fiber is typically a laser, which makes it more expensive than multimode fiber.

Multimode Fiber

By comparison, multimode fiber cable, with a diameter of about 62.5 microns, allows multiple mode of light to propagate through it simultaneously, thus forming mode dispersion. Mode dispersion technology limits the bandwidth and distance of multimode fiber. Therefore, multimode fiber features larger core diameter and short transmission distance. Multimode fiber typically uses an LED to create the light pulse, which makes it cheaper than single-mode fiber.

Both single-mode and multimode fiber can handle 10G speeds. The most evident difference between them lies in the distance. Within a data center, it’s typical to use multimode fiber which can get you 300-400 meters. If you have very long runs or are connecting over longer distance, single-mode fiber can get you 10 km, 40 km, 80 km, or even farther. You just need to use the appropriate optic for the distance required.

Fiber Cable Uses

It’s widely acknowledged that optical cables are usually applied into computer networking and telecommunication due to its ability to transmit data and information. What’s more, it’s also used by military and space industries as means of communication and signal transfer, in addition to its ability to provide temperature sensing. In recent years, fiber cable is frequently used in a variety of medical instruments to provide precise illumination. An endoscope, for example, is a flexible tube containing several optical cables. When it slips into the patient’s mouth, nose, digestive tract, and other heart areas that are not visible outside the body, the doctor can see the changes through the endoscope. Other medical applications for fiber optics include X-ray imaging, biomedical sensors, light therapy and surgical microscopy.


From the aforementioned article, we can see that fiber optic cables have different types with different features, and are widely used in telecommunication, military, medical applications, etc. If you would like to know more or would like assistance in choosing the appropriate optical fiber cable, welcome to visit our website www.fs.com for more detailed information. FS will provide more choices and better services for our clients.

How to Select Waterproof Fiber Optic Patch Cable?

Fiber optic waterproof cables are widely used in outdoor applications to connect the major fiber optic lines or receivers or splice enclosures. According to different requirements, both fiber optic patch cords and fiber optic pigtails are available. Water proof fiber cable usually adds a water blocking material between the outer jacket and the inner fiber (or inner jacket) to protect the fiber surface from unwanted damage, such as an armored cable or loose-tube gel-filled cable, or water-tolerable tight-buffered cable. Since there are different types of structure for waterproof cables, is there an easy way to determine which waterproof fiber optic patch cable to choose? In order to help select a right waterproof fiber optic cable quickly, this post will introduce the basic knowledge of waterproof ratings and the features of our waterproof fiber optic cable.

LC-LC waterproof fiber patch cable

How Is a Waterproof Cable Rated?

Like choosing any other fiber optic patch cables, the connector type, fiber count, fiber type (single-mode or multimode), polish type, cable length and cable jacket are factors that should be considered as well. When buying waterproof fiber optic patch cords, the IP (International Protection or Ingress Protection) rating is an important parameter. Knowing the IP code can help you find your wanted waterproof cable.

IP rating system is a classification showing the degrees of protection from solid objects and liquids. IP rating codes do not include hyphens or spaces, and consist of the letters IP followed by one or two figures. The first number refers to the degree of protection against the entry of foreign solid objects, such as dust. These protection levels range from 0 to 6. The second number of the IP code refers to the degrees of protection against moisture/liquids, which are raging from 0 to 8. The first and second number of the IP code can be replaced by the letter “X” when the protection capacity against solid objects (the first number) or moisture (the second number) has not been tested, for example, IPX7 and IP6X.

The following two tables explain the two types of protection levels in details.

Table 1: Protection levels against solid objects.

IP Code Protection Object Size
0 No protection. N/A
1 Protection from contact with any large surface of the body, such as the back of a hand, but no protection against deliberate contact with a body part, such as a finger. Less than 50mm.
2 Protection from fingers or similar objects. Less than 12.5mm.
3 Protection from tools, thick wires or similar objects. Less than 2.5mm.
4 Protection from most wires, screws or similar objects. Less than 1mm.
5 Partial protection from contact with harmful dust. N/A
6 Partial protection from contact with harmful dust. N/A

Table 2: Protection levels against moisture.

IP Code Protection Test Duration Usage
0 No protection. N/A N/A
1 Protection against vertically dripping water. 10 mins Light rain.
2 Protection against vertically dripping water when device is tilted at an angle up to 15 degrees. 10 mins Light rain.
3 Protection against direct sprays of water when device is tilted at an angle up to 60 degrees. 5 mins Rain and spraying.
4 Protection from sprays and splashing of water in all directions. 5 mins Rain, spraying and splashing.
5 Protection from low-pressure water projected from a nozzle with a 6.3mm diameter opening in any direction. 3 mins from a distance of 3 meters Rain, splashing and direct contact with most kitchen/bathroom faucets.
6 Protection from water projected in powerful jets from a nozzle with a 12.5mm diameter opening in any direction. 3 mins from a distance of 3 meters Rain, splashing, direct contact with kitchen/bathroom faucets, outdoor use in rough sea conditions.
7 Protected from immersion in water with a depth of up to 1 meter (or 3.3 feet) for up to 30 mins. 30 mins Rain, splashing and accidental submersion.
8 Protected from immersion in water with a depth of more than 1 meter (manufacturer must specify exact depth). Varies Rain, splashing and accidental submersion.
Features of FS.COM Waterproof Fiber Optic Patch Cable

FS.COM provides IP67 waterproof fiber optic patch cable, including simplex, duplex, 12 fibers, 24 fibers, and various kinds of connect interfaces are optional, such as LC-LC fiber patch cord, SC-SC fiber patch cord, MPO-MPO fiber patch cord, etc. Other degrees of waterproof fiber optic patch cords can also be customized. Our waterproof fiber patch cables are designed with strong PU jacket and armored structure, which can resist high temperature and fit for harsh environment. Our IP67 waterproof fiber patch cords are featured with high temperature stability and low insertion loss. It is also very convenient to install these waterproof, dust-proof and corrosion-resistant patch cords. The plug and socket design can be used to extend the cable length. They are very suitable for FTTH (fiber to the home) and LAN (local area network) applications.


The IP code for waterproof devices is not that difficult to understand and you can get some basic information about the protection degree of a device after you know the meaning of each number. You can use it as a reference in choosing a waterproof cable, but you should also consider other factors according to your specific applications.

How to Deploy 10G, 40G, 100G in the Same Network

In 2010, 10G SFP+ became the primary equipment interface in data center applications. However, jump to 2017, as demand for greater bandwidth shows no signs of slowing, 40G and 100G transceiver shipments saw a whopping increase. While shipments of 40G and 100G modules are on the rise, the large majority of data center networks don’t undergo a whole replacement of 10G device with 40G or 100G device. Instead, many typically deploy necessary equipment to achieve the coexistence of 10G, 40G, and 100G in the same network. Read this post, and you will get detailed solution.

QSFP+ 40G to 10G

In the following scenario, an upgraded 40G switch is networked to existing 10G servers with a 1×24-fiber to 3×8-fiber MTP conversion cable. At the switch, a cassette combines three 40G ports (QSFP 8-fiber) on the 24-fiber trunk. In the server cabinet, each 40G port is segregated into 10G LC connections to support server connectivity.

QSFP+ 40G to 10G

Note: in this architecture, if you have existing 12-fiber MTP trunks, you can use a cassette with two 12-fiber MTP inputs that breakout into 3×8-fiber MTP strands, instead of deploying a new 24-fiber MTP trunk cable. However, if you have to move to denser and more complicated applications, the 24-fiber MTP solution makes for easier migration.

CFP2 100G Port (10×10)

Like the previous example, the following figure 2 also shows a similar scenario in existing 10G servers, but it uses 100Gbase-SR10 ports on the switch, which requires a 24-fiber connector to drive the 10×10 transceiver port. Instead of breaking into 8-fiber connections, it uses 24-fiber MTP patch cord from the switch to the patch panel in the top of the rack. A 24-fiber MTP trunk connects the switch and server cabinet. The MTP cassette at the top of the server cabinet converts the 100G port into ten individual 10G port with LC connectors.

CFP2 100G port (10x10)

Note: As in the figure 1, in this scenario, if you already have two 12-fiber MTP trunks, you can use 12-fiber MTP adapter panel, then a 2×12-fiber to 1×24-fiber MTP harness cable could be used at the switch to build the same channel.

New Installation for 40G/100G Deployment

Figure 3 shows an example of a completely new installation, using 40G/100G right out of the box without any 10G switches in the channel. This method has 40G or 100G port on the core switches, and 40G uplinks at the ToR switches. The patch panels at the top of each rack use MTP bulkhead, with all 8-fiber cords from one QSFP port to the next.

40G100G Deployment - New Installation

In this architecture, we can either use 24-fiber trunks that break into 40G ports, or create trunks with 8-fiber strands on every leg, with 8 fibers per 40G or 100G port, as shown in the diagram above. However, we have to pay attention that with 8-fiber legs, the density will become a challenge. In addition, 12-fiber MTP trunks are avoided in this scenario, since integrating existing 12-fiber trunks with 8-fiber connectivity on the patch cord creates fibers unused.

Deploying 10G, 40G, 100G in the same network can effectively avoid costly upgrades that require ripping out cabling and starting over with a new network architecture. This post have provided three solutions. All the devices in these three scenarios can be purchased in FS.COM. If you are interested, kindly visit FS.COM.

100G QSFP28 and CFP Transceiver Cabling Solutions

By the end of 2016, 100G Ethernet has been widely deployed and becomes a significant portion in data center. Many network-equipment developers are motivated to introduce 100G devices like CFP and QSFP28 modules that consumes as little real estate and power as possible, while achieving necessary price points and delivering superior performance. This post is heading to talk about these two 100G modules and their cabling solutions.

CFP: Out With the Old

Specified by MSA among competing manufacturers, CFP is the first generation 100G transceiver which is designed after the SFP interface, but is significantly larger to support 100Gbps. As we all know, the original CFP has very large size, and in order to meet the need for higher performance and higher density in data center, there is the development of CFP2 and CFP4 specification, which specify a form-factor of 1/2 and 1/4 respectively in size of the original specification. Commonly used CFP/CFP2/CFP4 transceivers are available in 100GBase-SR10 and 100GBase-LR4.

100GBase-SR10 and 100GBase-LR4 CFP

QSFP28: In With the New

QSFP28 is the latest 100G form factor, which is a high-density, high-speed product solution designed for applications in the telecommunications, data center and networking markets. It utilizes four channels of respective signals with data rates up to 25Gbps to meet 100Gbps Ethernet requirement. 100GBase-SR4 and 100GBase-LR4 are two main types of QSFP28 module. The detailed specifications of these two QSFP28s are shown in the following table.

100GBase-SR4 and 100GBase-LR4 QSFP28

100GBase-SR10 Cabling Solution

100GBase-SR10 CFP uses a 24 strand MPO cable for connectivity (10 Tx and 10 Rx with each lane providing 10Gbps, leaving 4 channels unused). It can support maximum link length up to 100m and 150m respectively on OM3 and OM4 fiber cable. 100GBase-SR10 can also be used in 10×10 Gigabit Ethernet modes along with ribbon to duplex fiber breakout cables for connectivity to ten 10GBase-SR optical interface.

100GBase-SR10 CFP Cabling Solution

100GBase-SR4 Cabling Solution

Like 100GBase-SR10, 100GBase-SR4 QSFP28 also uses laser optimized OM3 and OM4 multimode fiber for indication. But 100GBase-SR4 QSFP28 utilizes 12f MPO trunk cable for connectivity (4 Tx and 4 Rx, leaving the middle four unused), which makes it possible to reuse 40GBase-SR4 fiber assemblies when upgrade from 40G to 100G.

100GBase-SR4 QSFP28 Cabling Solution

100GBase-LR4 Cabling Solution

Both 100GBase-LR4 CFP and QSFP28 are both interfaced with LC connector. They uses WDM technologies to achieve 100G transmission over single-mode duplex LC fiber patch cable supporting the link length up to 10km.

100GBase-LR4 Cabling Solution


As the need for high bandwidth is increasing, 100G Ethernet will widespread in data center quickly. Equipped with this basic information about 100G modules and their cabling solutions, we will have little worry upgrading to 100G Ethernet.

100% Fiber Utilization with 2×3 MTP Conversion Cable

When faced with eight-fiber parallel applications, such as 40GBase-SR4 40 Gigabit Ethernet and 100GBase-SR4 100 Gigabit Ethernet, technicians who use conventional 12-fiber MTP cable will waste a third of the fibers in the cable plant (four fibers for transmitting and four fibers for receiving, leaving the middle four unused). To overcome this inefficiency, new 2×3 MTP conversion harness is introduced. 2×3 MTP conversion cable terminated with three 8-fiber MTP connectors on one end and two 12-fiber MTP connectors on the other end can convert the signal from three four-channel transceivers to two 12-fiber trunks, which means 100% utilization of a 12-fiber network. The following text will mainly talk about how 2×3 MTP conversion cable uses all the fibers in 10G to 40G and 40G to 40G connection.

2x3 MTP conversion cable

10G to 40G Connection With 2×3 MTP Conversion Cable

Although upgrading from 10G to 40G Ethernet becomes common in most data centers, it is still impossible to replace all the 10G devices with 40G devices for more cost consumption. There are many solutions that we have introduced in the previous articles used to connect 10G to 40G equipment. 2×3 MTP conversion cable is a cost-effective one. The scenario can be clearly see from the following image. The three 8-fiber MTP connectors terminated at the 2×3 MTP conversion cable are directly plugged into the three 40GBase-SR4 modules(100% fiber utilization), then all cable assemblies will be plugged into the QSFP+ interfaced switch. The conversion from 40G to 10G is the most important step in this connectivity. Here we may use MTP or MPO LC cassette (2x12MTP-12xLC cassette) to connect two 12-fiber MTP connectors at the other end of the conversion cable to twelve duplex LC patch cables. Then all the LC cable assemblies with 10GBase-SR modules will be directly plugged into the SFP+ port switch. The whole connection do not waste any fiber.

10G to 40G connection with 2x3 MTP conversion cable

Identifier FS.COM Products Description
A S5850-48S6Q 48x 10GbE SFP+ with 6x 40GbE QSFP+ Switch
B QSFP-SR4-40G  QSFP+ SR4 optics; 150m @ OM4 MMF, 100m@ OM3 MMF
C 2×3 MTP Conversion Cable 2xMTP to 3xMTP; 50/125μm MM (OM3)
D 2x12MTP-12xLC cassette MTP-12 to LC UPC Duplex 24 Fibers MPO/MTP Cassette, 10G OM3, Polarity A
E Duplex LC Patch Cable Duplex LC; OM3
F SFP-10G-SR SFP SR optics; 300m over OM3 MMF
G S3800-24F4S 20x 100/1000Base SFP with 4x 1GE Combo and 4x 10GE SFP+ Switch
40G to 40G Connection With 2×3 MTP Conversion Cable

In this scenario, the three 8-fiber MTP connectors at the end of the conversion cable are directly plugged into the 40G module, then into 40G switch. In order to make sure all the fibers can be used in this 40G to 40G connectivity, we may use a adapter panel to connect the two 12-fiber MTP connectors of the conversion cable to the two 12-fiber MTP connectors attached at the end of the other 2×3 MTP conversion cable. Then the three 8-fiber MTP harness end with 40G modules will be plugged into the QSFP+ port switch. If you feel confused with my sentences, more clear description is shown in the image below.

40G to 40G connection with 2x3 MTP conversion cable

Identifier FS.COM Products Description
A S5850-48S6Q 48x 10GbE SFP+ with 6x 40GbE QSFP+ Switch
B QSFP-SR4-40G  QSFP+ SR4 optics; 150m @ OM4 MMF, 100m@ OM3 MMF
C 2×3 MTP Conversion Cable 2xMTP to 3xMTP; 50/125μm MM (OM3)
D MTP Adapter Panel Fiber Adapter Panel with 4 MTP(12/24F) Key-up/Key-down Adapters
E 2×3 MTP Conversion Cable 2xMTP to 3xMTP; 50/125μm MM (OM3)
F QSFP-SR4-40G QSFP+ SR4 optics; 150m @ OM4 MMF, 100m@ OM3 MMF
G S5850-48S6Q 48x 10GbE SFP+ with 6x 40GbE QSFP+ Switch

You can gain great value to deploy 2×3 MTP conversion cable, which does not add any connectivity to the link and it allows 100 percent fiber utilization and constitute the most commonly deployed method. However, you have to notice that the use of the 2×3 MTP conversion cable assembly at the core spine switch is not desirable, because patching across blades and chassis is a common practice.

What Should We Prepare for 40/100G Migration?

As data center of all types continue to grow in terms of traffic and size, 40G and 100G Ethernet technology is no longer a pipe dream—it is well on the way and set to become the new standard for high bandwidth and intelligent architecture. Faced with this upcoming trend in data center, what preparation should we do? Read this post, and you will get some details.

LC or MPO Interfaced 40/100G Modules?

Normally, there are two interfaces that 40/100G transceivers use: LC and MPO. LC interfaced modules will be used over single-mode fiber for long distance data transmission, while MPO interfaced modules are commonly deployed with multimode fiber for short distance. However, there are also some transceivers not following this rule. For example, 40GBase-UNIV uses duplex LC connector, but it only supports 150 meters over OM3 or OM4 fiber, and 500 meters over single-mode fiber as we have mentioned in the previous post. Besides, 100GBase-PSM4 is a single-mode module, but it has MPO interface to achieve data transmission. Choosing LC or MPO interfaced 40/100G transceiver totally relies on the transmission distance that your practical application requires.

Type Fiber and Distance Connector
40GBase-SR4 100m(OM3) 150m(OM4) MPO(male/female)
40GBase-LR4 10km(SMF) Duplex LC
40GBase-UNIV 150m(OM3) 150m(OM4) 500m(SMF) Duplex LC
100GBase-SR4 100m(OM3) 150m(OM4) MPO (male/female)
100GBase-LR4 10km(SMF) Duplex LC
100GBase-PSM4 500m(SMF) MPO (male/female)
Keep Budgets Down with Pre-terminated Cabling System

Cost is always the most important factor that every IT managers and ordinary users will concern. Since the technology for 40G and 100G is not as mature as 10G, devices used in these high-speed networks are more expensive, so we should keep our budget down as possible as we can in every aspect in the process of 40/100G migration. Then pre-terminated cabling system is a good choice.

pre-terminated assemblies for 40/100G

Pre-terminated cabling system contains factory manufactured cables and modular components with connectors already attached. It comes in a number of different forms, from connectorized fan-outs and attached or discreet cassette modules to cable bundles utilizing both fiber and copper with protective pulling grips installed over the connectors at one end. With these pre-terminated cabling, the need for labor to make terminations on site will be mitigated. And fewer labor means more savings on the labor bill. As report indicates, using the pre-terminated approach can achieve a saving of 57 percent.

Punch Down Solution   Pre-terminated Cabling
Material Cost              1X            3.2X
Labor Cost              2X            1X
Total              1X            1.3X
Installation Time              10 Hrs            5 Hrs
Future-Proof Your Network with 24-Fiber Infrastructure

In many 40/100G cases, 12-fiber system is more recommended to use between core switched and the equipment distribution area in the data center, but actually, if you want to future-proof your network, try 24-fiber infrastructure. Why? Let’s have a quick comparison.

For typically 40GbE applications, the 4 right and 4 left fibers of a 12 fiber MPO connector are used for transmit and receive while the inner 4 fibers are left unused. For 24-fiber 40GbE application, all fibers are utilized in the MPO plug. 24 fibers, divided by the 8 fibers per circuit that are required, yields 3 full 40GbE connectors. For 100GbE applications, if we choose 12-fiber MPO connector, we need two connector and two MPO trunk cables, the middle 20 fibers are used for transmit and receive 10Gb/s while the 2 fibers on the right are left unused. However, in this case, we just need one MPO 24 connector and one 24f trunk cable. As data centers continue to be crowded with more cabling, with 24-fiber system, about 1-1/2 times more pathway space could be saved.

24 fiber system for 40/100G


With the rapid increase in bandwidth consumption, the migration from 10GbE to 40/100GbE is inevitable. Proper interfaced transceiver, pre-terminated cabling system and 24-fiber infrastructure are required to build a cost-effective and high density 40/100G data center. If you’re interested in the components that we have mentioned above, kindly visit FS.COM.