Category Archives: Fiber Optic Transceivers

What’s the Difference: FET-10G vs. SFP-10G-SR

You must be puzzled by the two different short reach optical transceivers for a long time: FET-10G vs. SFP-10G-SR. What’s their difference? Does the connection work if we connect Cisco Nexus switches with FET-10G on one end and SFP-10G-SR on the other end? With these questions in mind, I’d like to invite you to keep reading the article.

FET-10G vs. SFP-10G-SR Difference

FET-10G vs. SFP-10G-SR are Cisco brand for building short network. FET is short for “Fabric Extender”. Just as its name implies, this module can only support fabric links from a Nexus 2000 to a Cisco parent switch. Fabric Extender transceiver can support link lengths up to 100m over OM3 or OM4 multimode fiber cable. SFP-10G-SR transceiver supports link lengths of 26m on standard fiber distributed data interface-grade multimode fiber cable. The link lengths can reach up to 300m over OM3 fiber cable and 400m over OM4 fiber optic jumpers. You can learn some small differences from the following table.

SFP+ Wavelength(nm) Cable Type Interface Modal Bandwidth(MHz km) Max Cable Distance (m)
FET-10G 850 MMF Duplex LC 500 (OM2)

2000 (OM3)

4700 (OM4)

25

100

100

SFP-10G-SR 850 MMF Duplex LC 160

200 (OM1)

400

500 (OM2)

2000 (OM3)

4700 (OM4)

26

33

66

82

300

400

Can We Connect FET-10G With SFP-10G-SR

In Cisco Nexus switch, do the transceivers have t ends in order for the connection to work? Does FET module have to be linked with another FET module? Now there is a FET-10G module in Cisco Nexus 2000 series fabric extender and SFP-10G-SR in a Nexus 5000 series switch. Can this connection work normally? Before making a judgement, let’s first compare the power of FET-10G and SFP-10G-SR.

SFP+ Module Transmit Power (dBm) Receive Power (dBm)
Max. Min. Max. Min.
FET-10G -1.3 -8 -1 -9.9
SFP-10G-SR -1.2 -7.3 -1.0 -9.9

From the above chart, transmit power and receiver power are different. And it has mentioned before that FET-10G vs. SFP-10G-SR support different network distance over the same fiber cable. Therefore, we can get a conclusion that FET-10G transceiver have to be connected with another FET-10G module. If we build a connection with SFP-10G-SR into the Nexus 5000 and FET-10G in Nexus 2000, it won’t work.

For better connection, when using FET-10G fabric extender transceiver, you should follow these rules:
1. FET-10G only supports fabric links, for instance, fabric links from a Nexus 2000 series to a Cisco parent switch.
2. Cisco fabric extender transceiver must be connected to another fabric extender transceiver, FET-10G to FET-10G.
3. FET-10G can be used for Nexus Cisco 2200 uplinks.
4. FET-10G can support fabric links on Cisco 5000, 6000, 7000 series switch.

Can We Replace FET-10G with SFP-10G-SR Modules?

FET-10G transceiver is designed to connect Cisco Nuplink ports (fabric interfaces) with the upstream parent Cisco Nexus switch. We already know that we can’t intermix FET-10G with SFP-10G-SR modules. How about plugging SFP-10G-SR transceivers into the fabric ports to connect Cisco Nexus switches? That is to say, can we replace FET-10G with SFP-10G-SR?

The answer is yes. However, it’s more expensive compared with original Cisco SFP-10G-SR transceiver. FET-10G is to provide an uplink to a Fabric Extender and save you money. If you already have them, then use them. If you making a purchasing decision, buy the FET-10G or third-party SFP-10G-SR.

FET-10G vs. SFP-10G-SR

Conclusion

From this article, you can find FET-10G vs. SFP-1T-10G is specially designed for Cisco Nexus series switches. To make sure the right connection, bear in mind that use the sane transceivers on both sides, either FET or 10G-SR. You can replace FET-10G with SFP-10G-SR while you can’t do that in turn.

Tunable SFP+ VS. Fixed Wavelength DWDM SFP+ Transceiver

Dense wavelength division multiplexing (DWDM) is one of most important technologies to increase network transmission capacity. Early DWDM systems applied fixed wavelength DWDM transceivers and performance is good. However, as the demand for great traffic capacity keeps growing, more optical transceivers of different wavelengths are needed, leading to high cost. So how to deal with that? Tunable SFP+ arises your attention.

Tunable-SFP+

What Is Tunable SFP+

Conventional DWDM SFP+ transceivers use fixed-wavelength lasers as light sources. It means that many optical transceivers are needed for the wavelength channels in a DWDM system. While tunable SFP+ is different from fixed wavelengths modules because it applies tunable laser, which can operate at any channel wavelength, means that only one kind of transceiver is needed. Tunable lasers are now widely used as light sources in DWDM systems. Tunable SFP+ modules are only available in DWDM since CWDM grid is too wide. Tunable SFP+ optics are for the C-Band 50GHz. About 88 different channels can be set with intervals of 0.4nm, which is the 50GHz band.

For better understanding, I’ll show you a tunable module. This is a Cisco Compatible 10G DWDM C-band tunable SFP+ 50GHz Transceiver. It’s hot swappable, can support 10.3Gbps data rate up to the distance of 80km over single mode LC duplex fiber patch cable. Support 1563.86nm-1528.77nm C-band tunable wavelengths.

Cisco-tunable-SFP+ optics

What you should note is that wavelengths of tunable SFP+ can be tuned only when your Cisco/Juniper/Arista/etc switch supports. If your switch only support common fixed-wavelength DWDM SFP+, you need external software to change tunable optics into certain wavelength before putting into use.

Why Tunable SFP+ Is Better Than Fixed Wavelength SFP+?

Fixed wavelength SFP+ are still in the market and not too many problems found in use. So you may feel puzzled about choosing tunable SFP+ or fixed wavelength SFP+ as tunable SFP+ is more expensive. The following will tell you why you need tunable optics.

First, save you cost. With the development of optical communication systems, the shortages of fixed-wavelength laser gradually revealed. Conventional DWDM SFP+ can lead high costs. The number of wavelengths in DWDM 50GHz has reached the hundreds. Then spare modules of each laser should be prepared for protection of the system because you don’t know which module will break down and it’s difficult to predict the number of stock in specific channels. Therefore you have to buy large quantity of DWDM SFP+ modules with fixed wavelengths. While the tunable optics are configured with different DWDM wavelengths in one module. You can select the right wavelength you need based on your optical fiber communication environment. Tunable SFP+ are typically used as “spare-optics” to save you cost.

Second, flexible network management. When running a DWDM network with lots of nodes, for instance, up to 80 different wavelengths, management could be a nightmare. You have to prepare couple of DWDM SFP+ optics of each wavelength and possibly in different locations. Field engineers may not access network nodes as quickly as you wish. Thus tunable optics would be a good choice. Tunable optics could be configured for a specific wavelength to support bandwidth changes as needed in optical network.

Third, suitable for large network capacity. As the development of increasing network transport, 400G or 1T would be the trend. Then 400G and 1T transmission formats are expected to be bulky and not fit within 50GHz spacing. These future new data rate formats require that channel spacing is flexible, that your OTN system can adapt to new rates and can re-arrange channel spacing to find place for new rates in it. Tunable optics will double the number of channels supported in this transceiver module. Upgrading to 50GHz channel spacing doubles the capacity potential in Enterprise and Metro networks.

Choose Tunable SFP+ in the Long Run

Tunable SFP+ are high-performance optics which can be tuned to the appropriate wavelength in seconds. The ability to function on various wavelengths has set these optics apart from fixed-wavelength DWDM SFP+. Tunable SFP+ will become popular among DWDM systems due to their ease of spare use and flexibility. Tunable SFP+ would be a powerful and invaluable transmission tool in high-speed network. At present, many engineers are using fixed wavelengths SFP+ transceivers. Some may be stopped by the tunable SFP+ price. But in the long run, you are suggested to consider tunable SFP+.

Transceiver Solutions for Cisco Catalyst 9300 Series Switch

This year, Cisco unveiled the Catalyst 9000 family, shaping the new era of intent-based networking. The Network. Intuitive. The Cisco Catalyst 9000 Series switches are the next generation of enterprise-class switches built for security, Internet of Things (IoT), mobility, and cloud. The Cisco Catalyst 9000 Series switches come in three main varieties: The Catalyst 9300, the Catalyst 9400 and the Catalyst 9500. Here, the post will give an emphasis on Cisco Catalyst 9400 series switches and transceiver solution for them.

Overview of Cisco Catalyst 9300

The Catalyst 9300 Series is the next generation of the industry’s most widely deployed stackable switching platform. Built for security, IoT, and the cloud, these network switches form the foundation for Cisco’s Software-Defined Access, the leading enterprise architecture. In addition, the Cisco Catalyst 9300-based models support a variety of uplink modules for both copper and fiber uplink support. These models add even more flexibility to the interface choices that you can make in a single Cisco Catalyst 9300 Switch or in a stack of Cisco Catalyst 9300 Switches.

cisco catalyst 9300

Supported Transceiver Modules for Cisco Catalyst 9300

The Cisco Catalyst 9300 Series Switches support optional network modules for uplink ports. All modules are supported across all 9300 platforms:

  • 4 x 1 Gigabit Ethernet network module
  • 4 x 1, 2.5, 5, or 10 Gigabit Ethernet network module
  • 8 x 10 Gigabit Ethernet network module
  • 2 x 40 Gigabit Ethernet network module

100G Solution

Model Number Transceiver Description Interface Max Cable Distance
CFP-100G-SR10 100GBASE-SR10 CFP form factor transceiver module for multi mode fiber, short wavelength over 10 lanes, in the 850-nm wavelength window MTP/MPO-24 Up to 100m on OM3/<150m on OM4
CFP-100G-LR4 100GBASE-LR4 CFP form factor transceiver module for SMF, 4 LAN-WDM lanes in the 1310-nm wavelength window LC duplex 10km
CFP-100G-ER4 100GBASE-ER4 CFP form factor transceiver module for SMF, 4 LAN-WDM lanes in the 1310-nm wavelength window LC duplex 40km
QSFP-100G-SR4-S 100GBASE-SR4 QSFP form factor transceiver module for multi mode fiber, short wavelength over 4 lanes, in the 850-nm wavelength window LC duplex 100m
QSFP-100G-CWDM4-S 100GBASE CWDM4 QSFP form factor Transceiver for single mode fiber, 4 CWDM-WDM lanes in the 12761-1331-nm wavelength window LC duplex 2km
QSFP-100G-PSM4-S 100GBASE PSM4 QSFP form factor transceiver module for single mode fiber, short wavelength over 4 lanes, in the 1195-1325-nm wavelength window MTP/MPO-12 500m
QSFP-100G-LR4-S 100GBASE-LR4 QSFP form factor transceiver module for SMF, 4 LAN-WDM lanes in the 1310-nm wavelength window LC duplex 10km

40G Solution

Model Number Transceiver Description Interface Max Cable Distance
QSFP-40G-SR4 40GBASE-SR4 QSFP+ transceiver module for MMF, 4-lanes, 850-nm wavelength MTP/MPO 150m on OM4
QSFP-40G-CSR4 40GBASE-CSR4 QSFP+ transceiver module for MMF, 4-lanes, 850-nm wavelength MTP/MPO 400m on OM4
QSFP-40G-SR4-S 40GBASE-SR4 QSFP+ transceiver module for MMF, 4-lanes, 850-nm wavelength MTP/MPO 150m on OM4
QSFP-40G-SR-BD 40G QSFP Bi-Directional transceiver module for duplex MMF LC duplex 150m on OM4/100m on OM3/30m on OM2
QSFP-40G-ER4 40GBASE-LR4 QSFP40G transceiver module for Single Mode Fiber, 4 CWDM lanes in 1310nm window Muxed inside module LC duplex 40km
QSFP-40GE-LR4 100GBASE-LR4 QSFP form factor transceiver module for SMF, 4 LAN-WDM lanes in the 1310-nm wavelength window LC duplex 10km
WSP-Q40GLR4L 40GBASE-LR4 QSFP40G transceiver module for Single Mode Fiber, 4 CWDM lanes in 1310nm window Muxed inside module LC duplex 2km

25G Solution

Model Number Transceiver Description Connector Type Cable Type
SFP-H25G-CU1M 25G Copper Cable 1-meter SFP28 to SFP28 Passive Copper Cable
SFP-H25G-CU2M 25G Copper Cable 2-meter SFP28 to SFP28 Passive Copper Cable
SFP-H25G-CU3M 25G Copper Cable 3-meter SFP28 to SFP28 Passive Copper Cable
SFP-H25G-CU5M 25G Copper Cable 2-mete SFP28 to SFP28 Passive Copper Cable
SFP-25G-SR-S 25GBASE-SR SFP+ transceiver module for MMF, 850-nm wavelength LC duplex MMF

10G Solution

Model Number Transceiver Description Interface Max Cable Distance
SFP-10G-SR 10GBASE-SR SFP+ transceiver module for MMF, 850-nm wavelength LC duplex 300m over OM3
SFP-10G-SR-S 10GBASE-SR SFP+ transceiver module for MMF, 850-nm wavelength LC duplex 300m over OM3
SFP-10G-SR-X 10GBASE-LRM SFP+ transceiver module for MMF and SMF, 1310-nm wavelength LC duplex 300m over OM3
SFP-10G-LRM 10GBASE-LRM SFP+ transceiver module for MMF and SMF, 1310-nm wavelength LC duplex 220m
SFP-10G-LR 10GBASE-LR SFP+ transceiver module for SMF, 1310-nm wavelength LC duplex 10km
SFP-10G-LR-S 10GBASE-LR SFP+ transceiver module for SMF, 1310-nm wavelength LC duplex 10km
SFP-10G-LR-X 10GBASE-LR SFP+ transceiver module for SMF, 1310-nm wavelength LC duplex 10km
SFP-10G-ER-S 10GBASE-ER SFP+ transceiver module for SMF, 1550-nm LC duplex 40km
SFP-10G-ZR 10GBASE-ZR SFP+ transceiver module for SMF, 1550-nm LC duplex 80km
SFP-10G-BX40D-I 10G SFP+ Bidirectional for 40km, downstream LC duplex 40km
SFP-10G-BX40U-I 10G SFP+ Bidirectional for 40km, upstream LC duplex 40km
DWDM-SFP10G-49.32 10GBASE-DWDM 1549.32 nm SFP+ (100-GHz ITU grid) LC duplex 40km
DWDM-SFP10G-60.61 10GBASE-DWDM 1560.61 nm SFP+ (100-GHz ITU grid) LC duplex 40km
CWDM-SFP10G-1470 CWDM 1470 nm SFP+ 10 Gigabit Ethernet Transceiver Module LC duplex 20km
CWDM-SFP10G-1490 CWDM 1490 nm SFP+ 10 Gigabit Ethernet Transceiver Module LC duplex 20km
XENPAK-10GB-ER 10GBASE-ER XENPAK transceiver module for SMF, 1550-nm wavelength SC duplex 40km
XENPAK-10GB-LR 10GBASE-LR XENPAK transceiver module for SMF, 1310-nm wavelength SC duplex 10km
X2-10GB-LR 10GBASE-LR X2 transceiver module for SMF, 1310-nm wavelength SC duplex 10km
X2-10GB-SR 10GBASE-SR X2 transceiver module for MMF, 850-nm wavelength SC duplex 300m over OM3 MMF
XFP-10GLR-OC192SR Cisco multirate XFP transceiver module for 10GBASE-LR Ethernet and OC-192/STM-64 short-reach (SR-1) Packet-over-SONET/SDH (POS) applications,SMF LC duplex 10km
XFP-10GER-OC192IR Cisco multirate XFP transceiver module for 10GBASE-ER Ethernet and OC-192/STM-64 intermediate-reach (IR-2) Packet-over-SONET/SDH (POS) applications, SMF LC duplex 40km

Conclusion

Digital disruption is changing how we think about our networks. Whether customers or employees, the “experience” has become a strategic imperative. The Cisco Catalyst 9300 Series fixed access switches are designed to help you change your network from a platform of connectivity to a platform of services. If you are in need of compatible optical transceivers for Catalyst 9300, give FS.COM a shot. FS.COM provides a wide range of supported optical transceivers for Cisco Catalyst 9300 series switch. Each one of them has been tested with assured 100% compatibility to them.

What Kind of Switches and Patch Cables Should I Choose for SFP Transceiver?

Gigabit Ethernet has supplanted Fast Ethernet in wired local networks and becomes ubiquitous throughout the world, serving as one of the most prevalent enterprise communication standard. The Gigabit Ethernet standard supports a maximum data rate of 1 gigabit per second (Gbps)(1000 Mbps), 10 times faster than Fast Ethernet, yet is compatible with existing Ethernet. To link your switches and routers to a Gigabit Ethernet network, you need a Gigabit Ethernet transceiver as a transmission medium. This article intends to introduce the most commonly used one—SFP transceivers.

sfp

What Is SFP Transceiver?

SFP, short for small form-factor pluggable is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications. SFP transceiver can be regarded as the upgrade version of GBIC module. Unlike GBIC with SC fiber optic interface, SFP module is with LC interface and the main body size of SFP is only about half of GBIC so that it can save more space. SFP interfaces a network device mother board (for a router, switch, media converter or similar devices) to a fiber optic or copper networking cable. It is designed to support SONET, Gigabit Ethernet, Fibre Channel, and other communications standards.

Types & Applications of SFP transceivers

SFP transceivers are available with various transmitter and receiver types, which facilitates users to select the appropriate optical transceiver for different optical reach and optical fiber type (single-mode fiber or multimode fiber) required by different link. SFP transceiver modules can be divided into several different categories:

Types Transmission Medium Wavelength Distance
1000BASE-T SFP Twisted-pair cabling / 100 m
1000BASE-SX SFP Multimode fiber 770-860 nm OM1-275 m/OM2-550 m
1000BASE-LX/LH SFP SMF & MMF 1270-1355 nm MMF-550 m/SMF-5 km
1000BASE-ZX SFP Single mode fiber 1550 nm 70 km
1000BASE-EX SFP Single mode fiber 1310 nm 40 km
1000BASE-BX10 SFP Single mode fiber 1480-1500 nm downstream, 1260-1,360 nm upstream 10 km
CWDM and DWDM SFP Single optical fiber various wavelengths various maximum distances

SFP transceivers are found in Ethernet switches, routers, firewalls and network interface cards. Storage interface cards, also called HBAs or Fibre Channel storage switches, also make use of these modules. Because of their low cost, low profile, and ability to provide a connection to different types of optical fiber, SFP transceiver provides such equipment with enhanced flexibility.

FS.COM Compatible SFP Transceivers for Popular Switches

FS.COM offers a full range of SFP transceivers compatible with major brands, such as Cisco, Juniper, Arista, Brocade, HPE, etc. All of these cost-effective compatible SFPs have been strictly tested to make sure 100% compatibility. The table below listed a small part of compatible SFPs supported on major branded switches.

Brand Switch Series Model Port Description
Cisco Catalyst 6500 Series WS-SUP720-3BXL 2 SFP Port
VS-S720-10G-3C 4 SFP Port
WS-X6724-SFP 24 SFP Port
Nexus 9000 Series N9K-C9396PX 48 SFP Port
IE3010 Series IE-3010-24TC 2 SFP Port
ASR 9000 Series Router A9K-MPA-20X1GE 20 SFP Port
Juniper EX 4200 Series EX4200-24T 2 SFP Port
EX4200-48T 4 SFP Port
EX4200-24T-DC 2 SFP Port
MX480 Router MX480 Router 4 SFP Port
SRX Series SRX210 1 SFP Port (Option)
QFX 5100 QFX5100-48S 48 SFP Port
Arista 7500 Series DCS-7504 48 SFP Port (Option)
DCS-7508 48 SFP Port (Option)
7050SX Series 7050SX-64 48 SFP Port
7100 Series DCS-7124S 24 SFP Port
Brocade VDX 6720 BR-VDX6720-16-R 16 SFP Port
BR-VDX6720-24-F 24 SFP Port
BR-VDX6720-40-F 40 SFP Port
SX Series SX-424F 24 SFP Port
SX-FI12GM-4-PREM 12 SFP Port
Brocade BI-RX-8 NI-MLX-1Gx20-SFP 20 SFP Port
HPE ProCurve 5400zl Series J8697A 2 SFP Port
J9548A 144 SFP Port
FlexFabric 5800 Series JC101B 4 SFP Port
JG225B 6 SFP Port
5400R zl2 Series J9584A 24 SFP Port
StorageWorks edge 2/12 348406-B21 12 SFP Port

FS.COM Patch Cables for SFP Transceivers

FS.COM offers comprehensive fiber patch cables for common and special types of SFPs, including singlemode & multimode, simplex & duplex, UPC & APC, lengths from 1 meter to 30 meters in large stocks. We also provides Cat 5e patch cables for 10/100/1000BASE-T SFPs.

Fiber Mode Connector Jacket
9/125 SMF LC Duplex PVC/LSZH/OFNP
9/125 SMF LC Simplex PVC/LSZH
9/125 SMF SC Simplex PVC/LSZH
50/125 OM2 LC Duplex PVC/LSZH
62.5/125 OM1 LC Duplex PVC
Cat5e Patch Cables Max Distance Data Rate
Unshielded (UTP) 100m 1000Mbps
Shielded (FTP) 100m 1000Mbps

Summary

This article offers switch and fiber patch cabling solution for SFP transceivers. Besides the major brands mentioned above, we also provide SFP transceivers compatible with other brands, such as Dell, Extreme, H3C, Huawei, Intel, IBM, Netgear, Ciena, D-Link, Avago, and so on. As to special requirements, please contact Sales@fs.com for suggestion.

25GbE–A New Trend For Future Ethernet Network

Nowadays, the requirement for bandwidth in cloud data centers is increasing strikingly. To meet the demand for higher bandwidth, networking and the Ethernet industry are moving toward a new direction. Discussions previously focusing on 10GbE and 40GbE are now shifting onto 25GbE. It seems that 25GbE is more preferred and accepted by end users, which poses a threat to 10GbE and 40GbE. Why does it happen? This post will lead you to interpret 25GbE in an all-sided perspective.

25GbE–A New Trend for Future Ethernet Network

25GbE—An Emerging Standard

25GbE is a standard developed by IEEE 802.3 Task Force P802.3by in July 2014, used for Ethernet servers and switches connectivity in a data center environment. The single lane design of 25GbE gives it a low cost per bit, which enables cloud providers and large-scale data center operators to deploy fewer switches and cables to meet the needs while still scaling their network infrastructure. The following table provides a summary of key upcoming IEEE standard interfaces that specify 25GbE.

25GbE–A New Trend for Future Ethernet Network

Figure 1: IEEE 802.3 standard Interfaces that specify 25GbE

Cloud Will Drive to QSFP28 and SFP28

The 25GbE physical interface specification supports two main form factors—SFP28 and QSFP28.
SFP28 is used for a single 25GbE port. The SFP28-25G-SR-S is an 850nm VCSEL 25GbE transceiver which is designed to transmit and receive optical data over 50/125µm multimode fiber (MMF) and support up to 70m on OM3 MMF and 100m on OM4 MMF.

The QSFP28 transceiver and interconnect cable is a high-density, high-speed product solution designed for applications in the telecommunication. The interconnect offers four channels of high-speed signals with data rates ranging from 25 Gbps up to potentially 40 Gbps, and will meet 100 Gbps Ethernet (4×25 Gbps) and 100 Gbps 4X InfiniBand EDR requirements.

100GBASE-SR4-with-four-25GBASE-SR-SFP28

Figure 2: FS.COM optical transceivers for 25GbE solution

Why Choose 25GbE

While 10GbE is fine for many existing deployments, it cannot efficiently deliver the bandwidth required by next-generation cloud and web-scale environments. And 40GbE isn’t cost-effective or power-efficient in ToR switching for cloud providers. Thus, 25GbE was designed to break through the dilemma.

Number of SerDes Lanes

SerDes is an integrated circuit or transceiver used in high-speed communications for converting serial data to parallel interfaces and vice versa. The transmitter section is a serial-to-parallel converter, and the receiver section is opposite. Currently, the rate of SerDes is 25 Gbps. That is to say, we can only use one SerDes lane at the speed of 25 Gbps to connect from 25GbE card to the other end of 25GbE card. In contrast, 40GbE needs four 10GbE SerDes lanes to achieve connection. As a result, the communication between two 40GbE cards requires as many as four pairs of fiber. Furthermore, 25 Gbps Ethernet provides an easy upgrade path to 50GbE and 100GbE networks, which utilize multiple 25GbE lanes.

Numbers of lanes needed in different Gigabit Ethernet

Figure 3: Numbers of lanes needed in different Gigabit Ethernet

Utilization of PCIe Lanes

At present, the mainstream Intel Xeon CPU only provides 40 lanes of PCIe 3.0. The lane bandwidth of a single PCIe 3.0 is about 8 Gbps. These PCle lanes are used for many connections. Therefore, it is necessary to consider the utilization of limited PCIe lanes by the network cards. Single 40GbE NIC needs at least one PCIe 3.0 x8 slot, so two 40GbE cards need to occupy two PCIe 3.0 x8 lanes. Even if the two 40GbE ports can run full of data at the same time, the actual lane bandwidth utilization is only: (40G+40G) / 8G*16= 62.5%. On the contrary, 25GbE card only needs one PCIe 3.0 x8 lane, and then the utilization efficiency is 25G*2 / (8G*8) = 78%. Apparently, 25GbE is significantly more efficient and more flexible than 40GbE in terms of the use of PCIe lanes.

10GbE vs 25GbE vs 40GbE

25GbE enables resellers and their customers to provide 2.5X the performance of 10GbE, making it a cost-effective upgrade to the 10GbE infrastructure. Since 25GbE is delivered across a single lane, it provides greater switch port density and network scalability compared to 40GbE, which is actually four 10GbE lanes. Thus, it costs less, requires lower power consumption and provides higher bandwidth. What’s more, 25GbE can run over existing fiber optic cable plant designed for 10, 50 or 100GbE and also 40GbE by changing the transceivers.

Bandwidth comparison for 25GbE and other Ethernet speeds

Figure 4: Bandwidth comparison for 25GbE and other Ethernet speeds

Summary

No matter the market research or the attitude of users, 25GbE seems to be the preferred option down the road. Actually, coming back to reality, there will be a significant increase in 100GbE and 25GbE port density in the next few years. If you need any optics and cabling solution for your 25GbE infrastructure, feel free to contact sales@fs.com.

How to Get 40/100G Connectivity in Your Data Center?

The demand for network growth is rapidly increasing, which is due to the massive amount of storage needed for high bandwidth applications. Large growth hence spurs the requirements for expansion and scalability in the data center. Cabling infrastructures must evolve to provide reliability, manageability and flexibility. Obviously, the conservative 2-fiber transmission is not enough to catch up with the speed. And 12 or 24-fiber 40/100G Ethernet migration is quickly becoming a matter of survival. This article offers cabling solutions for cost-effective and simplified migration for 40/100G within the data center.

Introduction to 40/100G Ethernet

40G and 100G Ethernet employ parallel optics. Parallel optics transmission, compared to traditional serial transmission, uses an optic module interface where data is simultaneously transmitted and received over multiple fibers. For the 40GE transmission, 4 x 10G on 4 fibers per direction and 10 x 10G on 10 fibers per direction for the 100GE. Which ushers the need for the high quality and low loss multimode MTP connectors and assemblies.

How to Get 40G Connectivity?
1). 10G to 40G Connection

Migration from 10G to 40G system utilizes 40G MTP/MPO breakout cables, with an MTP/MPO connector on one end and four duplex LC connectors on the other end. The IEEE ratified the 40GBASE-SR4 (MPO/MTP interface) standard that uses 4 lanes at 10G SFP+ (LC interface) per lane over multimode fiber for a total of 8 fibers.

Parallel optics 40GBASE-SR4 uses 8 out of 12 MTP/MPO interfaces fibers transmitting 4 duplex channels (4 for transmit and 4 receive), as shown in the following picture. QSFP+ to SFP+ breakout cable is 8-fibers MTP to LC breakout assembly.

10G-40G migration solution 1

2). 40G to 40G Connection

As for data transmission between two 40G switches, 40G QSFP+ SR4 transceivers are generally adopted, transmitting signals over four duplex 10G lanes (4 transmit and 4 receive). A 12-fiber MTP/MPO trunk are involved, with 8 out of 12 fibers used to achieve 4 duplex signals transmission. And MTP/MPO adapter panels can be installed easily to make the next adaptation, as the following picture indicates.

10G-40G migration solution 2

How to Get 100G Connectivity?
1). 10G to 100G Connection

Migrating from 10G to 100G still utilizes 100G MTP/MPO breakout cable, the IEEE ratified the 100GBASE-SR10 (MTP/MPO interface) standard that uses 10 lanes at 10G SFP+ per lane over multiple fiber for a total of 20 fibers. Parallel optics 100GBASE-SR10 uses 20 out of 24 MTP/MPO interface fibers transmitting 10 duplex channels.

10G-100G migration solution 1

2). 100G to 100G Connection

100G connectivity can be achieved through ten 10G SFP+ transceivers. SFP+ transceiver operates on legacy duplex 10G lanes, thus taking full advantage of the existing network infrastructure. With a 24-fiber MTP/MPO trunk cable, of which 20 out of the 24 fibers are used to make duplex 10×10G transmission.

10G-100G migration solution 2

We can also get 100G to 100G connectivity via MTP/MPO assemblies: simply use the 24-fiber MTP/MPO interface trunk cable or 2×12-fiber MTP/MPO interface trunk cable. As shown in the following picture.

40G-100G migration solution 1

Conclusion

With the rapid increase in bandwidth consumption, the migration from 10G to 40G or 100G is inevitable. The economics of cost per port per 10Gbps is much more favorable for a 40GBASE-SR4 and 100GBASE-SR10 network. All the transceivers and cabling assemblies presented in the solutions are available in FS.COM. For more details, please visit www.fs.com or contact us via sales@fs.com.

Which 40G QSFP+ Transceivers Can Be Used for 4x10G?

Since the overwhelming growth in data traffic, many data centers are loaded with 10G and 40G based Ethernet switches for 10G to 40G migration. 40G switches allow the configuration of 40G port to act as one port or break out into four individual ports. To get easy 10G/40G migration, we should better select 40G QSFP+ transceivers which can break out as 4x10G connectivity. Among so many versions of 40G QSFP+ transceivers including QSFP-40G-SR4, QSFP-40-CSR4, QSFP-40G-LR4, QSFP-40G-ER4, etc., which 40G QSFP+ transceiver can be used for 4x10G?

QSFP-40G-SR4/CSR4 for 4x10G

40G short distance multimode transceivers are interfaced with 12-fiber MTP/MPO, such as 40G SR4, CSR4. To know why these 40G QSFP+ modules can be used for 4x10G, let’s see how QSFP-40G-SR4 work? First, 4 electrical input signals of 10G converted into parallel optical signals are sent from the transmitter over 4 parallel fiber strands. Then the parallel optical signals are converted into parallel electrical signals by the use of a photo detector array and transmitted to the receiver over another 4 parallel fiber strands. QSFP-40G-SR4 needs 8 fibers to transmit and receive signals. QSFP-40G-SR4 transceivers are interfaced with 12-fiber MTP/MPO. Therefore, QSFP-40G-SR4 and QSFP-40G-CSR4 transceivers can be easily broken down to 4x10G connections. Each 10G signal lane of QSFP-40G-SR4 is compliant to IEEE 10GBASE-SR specifications. And this 10G/40G connection can be achieved by using an MTP-LC harness cable or MTP cable and MTP-LC breakout patch panel to connect the QSFP-40G-SR4 and four 10GBASE-SR modules.

QSFP-SR4-4x10G

Can QSFP-40G-LR4/ER4 Be Used for 4x10G?

QSFP-40G-LR4 transceivers apply CWDM (Coarse Wavelength Division Multiplexing) technology. From the transmitter side, 4 input electrical signals of 10G are converted into 4 CWDM optical signals by a driven 4-wavelength distributed feedback (DFB) laser array. Then 4 CWDM signals are multiplexed to a singlemode fiber for 40G optical signal transmission. On the receiver side, the receiver accepts 40G CWDM optical signals input and demultiplexes them into 4 individual 10G optical data streams with different wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed in the device. The 40 Gigabit Ethernet signal is carried over four wavelengths on a pair of singlemode fibers. The duplex fibers are used for bi-directional transmission. QSFP-40G-LR4 and QSFP-40G-ER4 are interfaced with duplex LC connector. Therefore, we can’t split QSFP-40G-LR4 or QSFP-40G-ER4 to 4 individual duplex SMF fibers to route them to 4 separate 10G transceivers by simple optical rerouting.

QSFP-LR4-4x10G

But if you insist to split the 40G into four 10G streams using QSFP-40G-LR4 or QSFP-40G-ER4 modules, how to achieve that connection? Then you need a simple multiplexer/demultiplexer which split the four wavelengths on duplex fibers into 4x10G signal in four different fibers. With such equipment, the QSFP-40G-LR4 or QSFP-40G-ER4 outputs can be physically broken down from one duplex fiber into four duplex fibers so that each of the wavelengths is transmitted in four different fibers (As the following figure shows).

QSFP-LR4-4x10G-cable

How About QSFP-40G-PLRL4?

From the above content, you may get an inclusion that multimode 40G QSFP+ transceivers can be directly used as 4x10G while singlemode 40G QSFP+ transceivers can’t. However, you ignore one singlemode transceiver QSFP-40G-PLRL4. This 40G QSFP+ transceiver connects with 12-fiber MTP/MPO patch cable though it’s designed for long distance transmission. Similar to QSFP-40G-SR4, QSFP-40G-PLRL4 also needs 8 fibers to transmit and receive signals. So you can easily get 10G/40G singlemode connection applying QSFP-40G-PLRL4.

Summary

Some data centers may face the issue of migration from 10G to 40G. Except the switch, you also need to know 40G QSFP+ transceivers well especially what kind of 40G QSFP+ transceivers can be used for 4x10G connectivity. In this article, you can see 40G QSFP+ transceivers with MTP/MPO interface can achieve that connection by simple optical routing. As to 40G QSFP+ transceivers with duplex LC interface, you need spare equipment for multiplexing/demultiplexing. For 40G to 4x10G solutions, you can find your desired one from FS.COM.

Related article: How to Extend 40G Connection up to 80 km?

QSFP+ to 4xSFP+ AOC and QSFP+ MTP Breakout Cable Solution

How to Select Fiber Patch Cable for 40G QSFP+ Modules?

How to Extend 40G Connection up to 80 km?

As 40G connectivity is accelerating, many data centers prepare to migrate from 10G to 40G. But the link distance between 10G and 40G switches is a big challenge. This article can help you extend 40G connection distance.

Current 40G QSFP+ to 4x10G Connection—Max 10 km

As we know, 40GBASE-SR4 QSFP+ is designed for short distance of up to 150m connection. 40GBASE-PLR4 QSFP+ can support long distance link of up to 10 km. Both 40G QSFP+ modules are interfaced with 12-fiber MTP/MPO and can break out into 4x10G connection. To build 10G-40G connection, for instance, using singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4x10G SFP+ modules. As the direct connection distance between two 40GBASE-PLR4 QSFP+ optics can reach at most 10km, it’s easy to understand that the connection between 10G and 40G may be shorter. However, we provide a method to extend 40G connection to 80km distance. Continue to read this article and find the answer.

10km max

Equipment for Extending 40G QSFP+ Connection

To extend 40G QSFP+ connection distance, we have to use WDM transponder OEO (Optical-Electrical-Optical) repeater. OEO repeater allows connection between fiber to fiber Ethernet equipment, serving as fiber mode converter, or as fiber repeater for long distance transmission. It can also function as CWDM/DWDM optical wavelength conversion. Now we will use a multi-service transport system, including a hot-swappable plug-in OEO card which only occupies 1 slot. The other space can be left for holding more cards such as DCM, EDFA, OLP. On the left side, there is a card for centralized network management.

WDM transponder oeo

This is a 4-channel multi-rate WDM transponder with an OEO-10G card containing 8 SFP/SFP+ slots and can support up to 11.3G rate. The OEO card can convert 1G~11.3 Gbps Ethernet signals into a corresponding wavelength in CWDM and DWDM network infrastructures. Transmission distance can reach 80 km.

Except WDM transponder OEO repeater, we still need DWDM Mux/Demux and DWDM SFP+ to extend the distance to 80 km. DWDM Mux/Demux is to combine 4x10G signals of different wavelengths on one single fiber so that it’s the best solution to increase network capacity and save cost. Here we use 40-channel C21-C60 dual fiber DWDM Mux/Demux. So we can choose suitable 10G DWDM SFP+ modules 80km transceiver between the wavelengths of C21 and C60.

For your reference, the equipment for 40G connection extension mentioned above are from FS.COM. You can select those of other specifications according to your own needs.

Equipment Details
Fiber Transceiver 40GBASE-PLR4 QSFP+ 1310nm 10km MTP/MPO Transceiver
Generic Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver
C21-C60 DWDM SFP+ 80km DOM Transceiver
Transponder Repeater 4-channel WDM transponder OEO repeater
DWDM Mux/Demux 40 Channels C21-C60 Dual Fiber DWDM Mux Demux with Monitor Port, 3.0dB Typical IL
Extend 40G QSFP+ Connection to 80 km

Install 40GBASE-PLR4 QSFP+ into QSFP+ port of a switch and 4 10GBASE-LR SFP+ into the Ethernet ports of the WDM transponder OEO repeater. Then plug a singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4 SFP+ modules. Because of the OEO repeater function, 4x10G Ethernet signals are converted into corresponding wavelengths in DWDM network infrastructure. Then install 4 x 10G DWDM SFP+ transceivers into other four ports of OEO repeater. Next step is to connect DWDM SFP+ modules on the OEO repeater and DWDM Mux/Demux by using LC duplex patch cables. In this way, 40G QSFP+ distance can be extend up to 80 km.

40G-80km

Conclusion

10 km transmission distance is not the limit of 40G to 4x10G connection. From this article, you can extend 40Q QSFP+ to 80 km by mainly applying WDM transponder OEO repeater, DWDM Mux/Demux and 10G DWDM SFP+. If need to break your network distance limit, please visit our site www.fs.com or contact us via sales@fs.com.

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Economically Increase Network Capacity With CWDM Mux/DeMux
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User Guide for CWDM MUX/DEMUX

Difference Between QSFP, QSFP+, QSFP28

SFP is short for small form factor. It refers to fiber optic transceivers supporting 1Gbps data rate. Except SFP, current market is full of various types of fiber optic transceivers, such as QSFP, QSFP+ and QSFP28. At the first sight, these transceiver modules are very similar. But actually, they have big differences. To know the difference clearly is good to make the right choice for your network connection. So what are the differences between QSFP,  QSFP+, QSFP28?

QSFP vs QSFP+

“Q” of QSFP means quad (4 channels). QSFP is a compact, hot-pluggable transceiver used for data communications. The QSFP specification supports Ethernet, Fibre Channel, InfiniBand and SONET/SDH standards with different data rate options. QSFP transceivers support the network link over singlemode or multimode fiber patch cable. QSFP modules are commonly available in several different types: 4x1G QSFP, 4x10G QSFP+, 4x28G QSFP28. From this side, QSFP vs QSFP+ vs QSFP28 all share the same small form-factor. literally QSFP uses 4x1G lanes and was only found in some FC/IB contexts.

While QSFP+ transceivers, evolving from 4x1G lanes (QSFP) to 4x10G lanes, are designed to support 40G Ethernet, Serial Attached SCSI, QDR (40G) and FDR (56G) Infiniband, and other communications standards. QSFP+ standard is the SFF-8436 document which specifies a transceiver mechanical form factor with latching mechanism, host-board electrical-edge connector and cage. QSFP+ modules integrates 4 transmit and 4 receive channels plus sideband signals. Then QSFP+ modules can break out into 4x10G lanes. QSFP+ modules are used to connect switches, routers, Host Bus Adapters (HBAs), enterprise data centers, high-performance computing (HPC) and storage. But some may think QSFP as the same with QSFP+, especially in the Ethernet world.

QSFP+ vs QSFP28

QSFP+ and QSFP28 differs in “28” as the name says. QSFP28 is a hot-pluggable transceiver module designed for 100G data rate. QSFP28 integrates 4 transmit and 4 receiver channels. “28” means each lane carries up to 28G data rate. QSFP28 can do 4x25G breakout connection, 2x50G breakout, or 1x100G depending on the transceiver used. While QSFP+ supports the data rate of 40G, 4 channels for transmitting and 4 channels for receiving, each lane carrying 10G. QSFP+ can break out into 4x10G or 1x40G connection.

qsfp28 vs qsfp+

Usually QSFP28 modules can’t break out into 10G links. But it’s another case to insert a QSFP28 module into a QSFP+ port if switches support. At this situation, a QSFP28 can break out into 4x10G like a QSFP+ transceiver module. One thing to note is that you can’t put a QSFP+ transceiver into a QSFP28 port to avoid destroying your optics.

FS.COM QSFP+ vs QSFP28

Compatible with major brands such as Cisco, Juniper, Arista, Brocade, etc., FS.COM QSFP+ and QSFP28 modules can support both short and long-haul transmission. Here lists our generic QSFP+ and QSFP28 modules in the following table.

FS.COM Generic QSFP+
Model Description Price List In Stock
17931 40GBASE-SR4 QSFP+ 850nm 150m MPO Transceiver for MMF US$ 49.00 1061 pcs
34917 40GBASE-PLRL4 QSFP+ 1310nm 2km MPO Transceiver for SMF US$ 220.00 49 pcs
24422 40GBASE-LR4 and OTU3 QSFP+ 1310nm 10km LC Transceiver for SMF US$  340.00 50 pcs
34912 40GBASE-CSR4 QSFP+ 850nm 400m MPO Transceiver for MMF US$  70.00 141 pcs
35205 40GBASE-UNIV QSFP+ 1310nm 2km LC Transceiver for SMF&MMF US$  340.00 18 pcs
34913 40GBASE-LR4L QSFP+ 1310nm 2km LC Transceiver for SMF US$ 340.00 44 pcs
48721 40GBASE-SR Bi-Directional QSFP Module for Duplex MMF US$  300.00 106 pcs
35209 40GBASE-PLR4 QSFP+ 1310nm 10km MPO Transceiver for SMF US$  380.00 34 pcs
35211 40GBASE-ER4 and OTU3 QSFP+ 1310nm 40km LC Transceiver for SMF US$  1,500.00 40 pcs
39986 40GBASE-LR4 CFP 1310nm 10km SC Transceiver for SMF US$  800.00 Available
FS.COM Generic QSFP28
Model Description Price List In Stock
35182 Generic Compatible QSFP28 100GBASE-SR4 850nm 100m Transceiver US$ 270.00 38 pcs in stock
65216 Generic Compatible QSFP28 100GBASE-PSM4 1310nm 500m Transceiver US$ 750.00 26 pcs in stock
65214 Generic Compatible QSFP28 100GBASE-CWDM4 Lite 1310nm 2km Transceiver US$ 1,350.00 26 pcs in stock
65215 Generic Compatible QSFP28 100GBASE-CWDM4 1310nm 2km Transceiver US$ 1,350.00 26 pcs in stock
39025 Generic Compatible QSFP28 100GBASE-LR4 1310nm 10km Transceiver US$ 2,800.00 Available
Conclusion

The difference between QSFP vs QSFP+ vs QSFP28 has been stated clearly in this article. Though QSFP is thought as QSFP+, when talking about 40G, actually we mean QSFP+. QSFP+ vs QSFP28 mainly differs in data rate and breakout connection. So you must be sure what you need is 40G QSFP+ or 100G QSFP28 for high density applications, especially when connecting with 10G SFP+.

Related Article:  How to Match Fiber Patch Cable for Your Multimode SFP?

Which One to Select, GLC-LH-SM Vs GLC-LH-SMD?

Among so many different Cisco SFP modules, sometimes you may feel confused. Because the differences of some SFP modules are tiny, for instance, Cisco SFP GLC-LH-SM and Cisco SFP GLC-LH-SMD. If you can’t understand the the difference between these two Cisco SFP modules, you don’t know which one to select for your Cisco switch. This article is gonna explain GLC-LH-SM vs GLC-LH-SMD.

Cisco SFP GLC-LH-SM

Cisco SFP GLC-LH-SM is a hot swappable transceiver module that transfers the data rate of 1 Gbps. It’s compliant with IEEE 802.3 1000BASE-LX/LH standard. It supports the link lengths up to 10 km over single mode fiber patch cable at a wavelength of 1310 nm. It can be also applied for short network connection over multimode fiber cable (550 m).
Other features:
Interface: LC duplex
Tx power: -9.5 ~ -3dBm
Receiver Sensitivity < -23dBm
Commercial Temperature Range: 0 to 70°C (32 to 158°F)
DOM Support: No

Cisco SFP GLC-LH-SM

Cisco SFP GLC-LH-SMD

Cisco SFP GLC-LH-SMD is a hot pluggable transceiver module running the data rate at 1 Gbps. This SFP is interfaced with 1000BASE-LX/LH ports. And it can support both single mode and multimode applications.
Other features:
Interface: LC duplex
Tx power: -9.5 ~ -3dBm
Receiver Sensitivity < -23dBm
Commercial Temperature Range: 0 to 70°C (32 to 158°F)
DOM Support: Yes

GLC-LH-SM vs. GLC-LH-SMD Similarities

Cisco SFP GLC-LH-SM and Cisco SFP GLC-LH-SMD are both used for 1Gbps Ethernet network. They support with IEEE 802.3 1000BASE-LX/LH standard and are compatible with each other. The two Cisco SFP modules can be connected with single mode and multimode LC fiber patch cable. If one switch supports Cisco SFP GLC-LH-SM, then it can also support Cisco SFP GLC-LH-SMD. Here are supported switches for these two Cisco SFP modules: Catalyst Express 500, Catalyst Express 520, Cisco ME 3400, Cisco ME 4900 series, Cisco ME 6500 series, Catalyst 2940 series, Catalyst 2950 series, Catalyst 2960 series, Catalyst 2960 S series, Catalyst 2970 series, Catalyst 3560 series, Catalyst 3560 E series, Catalyst 3560-X series, Catalyst 3750 series, Catalyst 3750-E series, Catalyst 3750-X series, Catalyst 4500series, Catalyst 4900 series, Catalyst 6500 series, cisco IE3010 series.

GLC-LH-SM vs. GLC-LH-SMD Differences

The difference between Cisco SFP GLC-LH-SM and Cisco SFP GLC-LH-SMD is that Cisco SFP GLC-LH-SMD has additional letter “D”. What does “D” mean?

There are two kinds of misunderstanding about “D”. Some think “D” represent “duplex”. Cisco SFP GLC-LH-SMD supports duplex interface. But Cisco SFP GLC-LH-SM should be connected with duplex LC patch cable. And nearly all SFP transceiver modules, except copper SFPs, are interfaced with duplex ports. So this understanding is obvious wrong. Some think that “D” means “ruggged”. This opinion is not true either. “Rugged” is abbreviated to “RGD”, for example, Cisco GLC-LX-SM-RGD Compatible 1000BASE-LX/LH SFP 1310nm 10km DOM Transceiver.

“D” of GLC-LH-SMD transceiver has additional support for Digital Optical Monitoring (DOM) capability. From the features stated above, Cisco SFP GLC-LH-SMD can support DOM function while Cisco SFP GLC-LH-SM can’t. DOM provides a diagnostic monitoring interface for optical transceiver modules. DOM supports monitoring of optic output power, optic input power, temperature, laser bias current, and transceiver voltage. When DOM is enabled, the system monitors the temperature and signal power levels for the optical transceiver modules in the specified ports. Console messages and syslog messages are sent when optical operating conditions fall below or rise above the SFP manufacturer-recommended thresholds.

Which to Select, GLC-LH-SM vs. GLC-LH-SMD?

Cisco SFP GLC-LH-SM and Cisco SFP GLC-LH-SMD are very similar and compatible with each other. The only difference is that the latter one has DOM function. SFP with DOM is better for transceiver and system protection. So you are suggested to select Cisco SFP GLC-LH-SMD. Except these two Cisco SFPS, you can find other Cisco compatible SFPs from FS.COM. For more information, please visit out site http://www.fs.com.

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