Wednesday, April 26, 2017

How to Choose Fiber Optic Cable for 10G SFP+ Optical Transceiver?

How to choose fiber optic cables for 10G SFP+ transceivers? It seems like a dumb question for most of the fiber optic technicians. However, there are still some people, especially the green-hand network installers, may not know the compatibility between fiber optic cables and optical transceiver modules. Today, I want to make a clear illustration of how to choose the right transmission media (OS2/OM3/OM4/Cat6/Cat6a) for 10G SFP+ optical transceiver modules.
Overview of SFP+ Optical Transceiver Module
Before coming to the main part of this article, let’s first have a brief overview of the SFP+ optical transceiver modules and 10G fiber & copper cables.
  • 10GBASE SFP+ optical transceivers
SFP+ optical transceivers, according to the IEEE standards, can be divided into several types, for example, 10GBASE-LRM SFP+, 10GBASE-LR, 10GBASE-ER SFP+, 10GBASE-ZR SFP+, 10GBASE-SR SFP+, 10GBASE-T SFP+. Each SFP+ optical transceiver type has its own specification and usage that are not be listed here. For more, please review the previous articles.
  • BiDi SFP+ Modules
Besides the above 10GBASE SFP+ modules, 10GBASE-CWDM SFP+, 10GBASE-DWDM SFP+ and SFP+ BiDi optical transceiver modules are also the most commonly used 10G SFP+ optics. SFP+ BiDi optical transceiver usually uses two different wavelength to achieve 10G transmission over one fiber. The most frequently used wavelength of BiDi optical module is 1310nm/1550nm, 1310nm/1490nm, 1510nm/1590nm.
  • CWDM/DWDM SFP+ Modules
The Coarse Wavelength-Division Multiplexing (CWDM) and Dense Wavelength-Division Multiplexing (DWDM) SFP+ optics are the convenient and cost-effective solution for the adoption of 10 Gigabit Ethernet in campus, data-center, and metropolitan-area access networks. This 10G fiber optic transceiver type can support up to eight channels of 10GbE over single-mode fibers for distance over 80km.
10G Fiber & Copper Patch Cables
Fiber optic cables can be categorized into two types: single-mode and multimode fiber optic cables. They have different core size and fiber optic transmission equipment, which makes them suitable in different applications. Single-mode fiber patch cables, or OS1/OS2 (OS1 is now not popular on the market) are normally used for long-distance transmission with laser diode based equipment.
OS2 OM4 Cat6a for 10G SFP+ module
Multimode fiber cables, or OM1/OM2/OM3/OM4, have a relatively large light carrying core, usually utilized for short-distance transmission with LED based equipment. OM1, with a core size of 62.5um, supports 1GB network within 300m. OM2 (50um) can support up to 10GB, with a distance of 600m. OM3 and OM4 are the laser-optimized multimode fibers, which can be used in 10GB network with a link length of 300m, 550m respectively. These types of optical cables can be also used on 40G/100G network utilizing a MTP/MPO connector.
Cat6/Cat6a cables are the Copper Ethernet Network cables used for 10G network. Compared with Cat5e (1 Gigabits of data) and Cat5 cables (10/100 Mbps), Cat6 is the Ethernet cable that can handle up to 10Gbps with the distance limited to 164ft. Cat6a is the advanced version of Cat6 cables that further reduce crosstalk, which makes it can support the full 328 feet of Ethernet cable.
Choosing Fiber Optic Cables for 10G SFP+ Optical Transceivers
As noted before, single-mode patch cables can be used for 10G 10GBASE-LRM SFP+, 10GBASE-LR SFP+, 10GBASE-ER SFP+, 10GBASE-ZR SFP+, 10GBASE-CWDM SFP+, 10GBASE-DWDM SFP+ and SFP+ BiDi modules.
Cable TypeConnectorMax Distance
10GBASE-LRM SFP+9/125 SMFLC Duplex200m
10GBASE-LR SFP+9/125 SMFLC Duplex10km
10GBASE-ER SFP+9/125 SMFLC Duplex40km
10GBASE-ZR SFP+9/125 SMFLC Duplex80km
CWDM SFP+9/125 SMFLC Duplex80km
DWDM SFP+9/125 SMFLC Duplex80km
SFP+ BiDi9/125 SMFLC/SC Simplex80km

Multimode fibers, especially the OM3 and OM4 cables, are supported for 10GBASE-SR SFP+ transceiver modules. The following chart displays the part No. of customized OM3 and OM4 cables.
Customized Part IDConnectorFiber ModePolish TypesJacketStock Length
17235LC Duplex50/125 OM4UPCPVC1m-30m (3ft-98ft)
17235LC Duplex50/125 OM4UPCLSZH1m-15m (3ft-49ft)
17235LC Duplex50/125 OM4UPCOFNP1m-15m (3ft-49ft)
12018LC Duplex50/125 OM3UPCPVC1m-30m (3ft-98ft)
12018LC Duplex50/125 OM3UPCLZSH1m-30m (3ft-98ft)
12018LC Duplex50/125 OM3UPCOFNP1m-15m (3ft-49ft)

Cat6 and Cat6a Patch cables can be only used on the 10GBASE-T SFP+ transceivers.
10GBASE-T RJ45 SFP+ Copper module
Keep in mind, the newly available SFP+ copper transceiver modules can only support up to 30m.
This article lists all the existing the 10G fiber & copper patch cables and SFP+ transceiver module types, as well as the guidance about how to select the right patch cables for 10G SFP+ optical transceivers. FS.COM offers a full range of SFP+ optical transceiver modules and patch cables. Please contact us if you need any help.

Monday, April 17, 2017

Comparing 10GBASE-T SFP+ Transceiver Module With SFP+ SR/LR Optics & SFP+ DAC Twinax Cables

1000BASE-T SFP modules are available on the market as soon as the certification of Gigabit Ethernet network. However, 10GBASE-T SFP+ modules, owing to the technology limit, have not been supplied by vendors to support 10G copper networks. Instead, IT managers tend to use the cost-effective SFP+ direct attach cables (DAC) for short-reach 10G applications. Today, here comes a big news—vendors like HPE, Prolab, and FS.COM begin to offer 10GBASE-T SFP+ transceiver modules. Do you feel curious about them? This article will unveil the mysterious point of the 10G copper transceivers, and make a detailed comparison with SFP+ fiber modules and DAC twinax cables.
10GBASE-T SFP+ Transceiver Modules
10GBASE-T SFP+ transceiver modules are designed to meet the requirement of 10G longer-reach applications. Compared with SFP+ twinax copper cables (maximum distance is 10m), SFP+ 10GBASE-T transceiver modules operate over Cat6a/Cat7 with a link length of up to 30m. Seen from the below image, SFP+ 10GBASE-T transceiver terminates with a RJ45 connectors, which can be directly used in the RJ45 ports of 10G switches and NIC cards. What’s more, 10GBASE-T SFP+ module is announced to have lower power consumption (2.5W) than SFP+ Twinax DAC cables (4-8W).
Figure 1 shows how to plug a Cat6 cables in a 10GbE SFP+ module.
SFP+ 10GBASE-T Module Vs. SFP+ SR/LR Transceivers
In order to have a better understanding of the 10G copper modules, let’s compare the SFP+ 10GBASE-T modules with SFP+ SR/LR Transceivers and SFP+ DAC Twinax cables.
Both of the SFP+ copper and fiber modules are hot-pluggable with a managed soft-start and are interoperable with any SFP+ cage and connector system. However, they have total different performance when plugging into the 10G switches. SFP+ 10GBASE-T module uses the Cat6a cables for a link length of 30 m over RJ45 connectors. SFP+ SR operates over OM3 cables with a distance of 300m over LC connectors. While SFP+ LR optics utilizes the OS2 LC duplex cables for a distance of 10 km.
Figure 2 shows the SFP+ 10GBASE-T Module (left) and SFP+ SR Transceivers (right).
Note that 10G SFP+ transceivers are nowadays much cheaper than the newly released 10G copper module. For your reference, at FS.COM, Cisco SFP-10G-SR is offered at $16, Cisco stable SFP-10G-LR is &34. While Cisco SFP-10G-T is $380.
SFP+ 10GBASE-T Module Vs. SFP+ DAC Twinax Cabling
Whether to use SFP+ 10GBASE-T module and Cat6a cables or directly use the SFP+ DAC twinax cables for 10G short-reach application, it depends on your own network infrastructure.
  • Linking Distance and Power Consumption
As noted before, the maximum linking distance of SFP+ 10GBASE-T module is 30m, while the SFP+ DAC twinax cable is 10m. Furthermore, SFP+ 10GBASE-T module have reduced the power consumption of 10G copper modules, which is a great news for the heavy-loaded 10G data center networks.
  • Costs
For 10G intra-rack connection, SFP+ DAC twinax cables obviously cost lower than SFP+ 10GBASE-T copper modules and cat6a cables do. And you should also count the expenditure of 10G switches and NIC cards. 10G switches that can support 10G RJ45 ports are not available nowadays.
  • Reliability
Compatible SFP+ Twinax cables have been used for years in 10G networks. So they are quite reliable. As for the SFP+ copper modules, RJ45 interface is rock solid. But many professionals said that technically it could work, but it is not supported for most of the switches. Thus, it is not popular nowadays.
Customers are very happy to see that there are new products kept coming out to keep in pace with the ever-increasing technology. SFP+ 10GBASE-T copper transceiver is introduced to have a better interoperability between existing fiber switches and 10G copper ports. Although there are still some unsolved problems of SFP+ 10GBASE-T transceiver module, we believe they will be solved in the near future.

Friday, April 14, 2017

How to Choose Fiber Optics for Mellanox ConnectX Ethernet Adapter Cards?

Mellanox ConnectX Ethernet adapter card provides high-performance networking technologies by utilizing IBTA RoCE technology, delivering efficient RDMA services and scaling in ConnectX-3, 4, 5, 6 EN 10/25/40/50/56/100/200GbE connection. The Mellanox ConnectX EN Ethernet card supports a full suite of software drivers like Microsoft Windows (including Windows 10), Linux distributions, VMware and Citrix XenServer. ConnectX Ethernet adapter card comes in several types for 10/25/40/50/56/100/200GbE network, such as ConnectX-3 EN, ConnectX-3 Pro EN, ConnectX-3 Pro EN 10GBASE-T, ConnectX-4, ConnectX-4 Lx EN, ConnectX-5 EN, ConnectX-6 EN adapter cards. In this article, we present an in-depth network-level performance evaluation of the Mellanox ConnectX Ethernet adapter cards and the supported fiber optic cabling.
Mellanox ConnectX Ethernet Adapter Card
Network Interface Card (NIC), also known as Network Interface Controller, Network Adapter, LAN Adapter or Physical Network Interface. All Mellanox 10/25/40/50/100/200 Gigabit Ethernet adapters deliver high-bandwidth and industry-leading Ethernet connectivity in enterprise data centers, high-performance computing, and embedded environments. From ConnectX-2 to ConnectX-6, Mellanox keep upgrading their Ethernet adapter cards to meet customers requirement.
Connectx-6 EN
ConnectX-6 EN—200Gb/s Adapter Card
ConnectX-6 EN 200Gb/s Adapter Card, launched last year, was the world-first 200Gb/s Ethernet network adapter card for Ethernet connectivity, sub-600 ns latency and 200 million messages per second. ConnectX-6 EN, seen in the image, provides two ports of 200Gb/s for Ethernet connectivity. As the first adapter to deliver 200Gb/s throughput, ConnectX-6 is the perfect solution to provide machine learning applications with the levels of performance and scalability that they require.
ConnectX-5 EN—Adapter Supporting 100Gb/s EthernetConnectX-5
ConnectX-5 just as the image shows, supports two ports of 100Gb/s Ethernet connectivity, sub-700 nanosecond latency, and very high message rate, plus PCIe switch and NVMe over Fabric offloads, providing the highest performance and most flexible solution for the most demanding applications and markets.
Table 1 presents the detailed information about Mellanox ConnectX-5 EN Ethernet Adapter Cards
Ordering Part No.DescriptionSpeedPortsConnectorsDimensions w/o Bracket
MCX515A-CCAT100GbE single-port QSFP28, PCIe3.0 x16, tall bracket, ROHS R6100GbE1QSFP2814.2cm x 6.9cm (Low Profile)
MCX516A-CCAT100GbE dual-port QSFP28, PCIe3.0 x16, tall bracket, ROHS R6100GbE2QSFP2814.2cm x 6.9cm (Low Profile)
MCX516A-CDAT100GbE dual-port QSFP28, PCIe4.0 x16, tall bracket, ROHS R6100GbE2QSFP2814.2cm x 6.9cm (Low Profile)
ConnectX-4 EN—Adapter Supporting 10G/40G/100Gb/s
ConnectX-4 LX ENConnectX-4 adapter cards have three different types: ConnectX-4 Lx EN Programmable Adapter Card, ConnectX-4 EN, ConnectX-4 Lx EN. ConnectX-4 Lx EN Programmable Adapter Card is listed in the right image. ConnectX-4 EN network is the single or dual port 100 Gigabit Ethernet adapter cards. ConnectX-4 Lx enables data centers to migrate from 10G to 25G and from 40G to 50G speeds at similar power consumption, cost, and infrastructure needs. If you are into this NIC card, you'd better look through their difference.
ConnectX-3 Pro EN—10/40/56 Gigabit Ethernet Network Interface Cards
ConnectX-3 Gigabit Ethernet interface card is one of the mostly used NIC cards nowadays. This kind of NIC card can support 10/40/56Gb/s Ethernet connectivitConnectX®-3 Pro Programmable Adapter Cardsy with hardware offload engines. The long-term goal at Mellanox ConnectX Gigabit Ethernet adapter card is to allow customers to wire once and switch protocols on the server and switch as required by workloads. Mellanox can presumably charge a premium for such capability, and ConnectX-3 silicon allows Mellanox to create fixed adapters and switches at specific speeds to target specific customer needs and lower price points, too. The image on the right display the ConnectX-3 Pro Programmable Adapter Cards.
For detailed information about ConnectX-3 Pro EN adapter cards, please see the Table 2.
Ordering Part No.DescriptionDimensions w/o Bracket
ConnectX-3 Pro EN Adapter Cards  
MCX311A-XCATSingle 10GbE SFP+10.2cm x 5.4cm
MCX312A-XCBTDual 10GbE SFP+14.2cm x 6.9cm
MCX313A-BCBTSingle 40/56GbE QSFP14.2cm x 5.2cm
MCX314A-BCBTDual 40/56GbE QSFP14.2cm x 6.9cm
ConnectX-2—Supporting 10G Ethernet Switches
ConnectX-2 Gigabit Ethernet Cards
Mellanox ConnectX-2 EN cards are the older cards for Ethernet only. That means that they will not work in Infiniband networks. In fact, there are still a few examples of OSes without ConnectX-2 support. Prime examples are FreeBSD 9.3 based FreeNAS and NAS4Free versions which did not have built-in support for the cards. The bottom line is that in terms of compatibility, one does need to verify these cards will work.
Many customers do use these in their Windows 10 home workstation for a 10Gb SFP+ back-haul network. Speeds are reliable and excellent. Nowadays, Mellanox does not supply this card, but ebay and Amazon do provide ConnectX-2 cards under $19.
How to Choose the Cables and Optical Modules for ConnectX-3 Ethernet Adapter Cards?
According to Mellanox, ConnectX-3 10G/40G/56G Ethernet adapter cards are interoperable with 10/40 Gb Ethernet switches. Passive copper cables with ESD protection are supported in this NIC card. ConnectX-3 cards can support up to 56Gb/s that can accommodate several fiber cables and optical transceiver types. Take the MCX313A-BCBT as an example, it has single 40GbE QSFP+ port. QSFP+ optical transceivers and DAC cables are feasible in this Ethernet Adapter Card. For the 10G SFP+ to 40G QSFP+ migration, Mellanox QSA (QSFP+ to SFP+) modules are required.
QSA Module
A previous article QSFP+ to SFP+ Adapter (QSA) Module Vs. QSFP+ to SFP+ Breakout Cable provides the detailed information about how to use the QSA module.
DAC Twinax or 10GBASE-T Copper Cable For ConnectX-2 NIC Cards
Mellanox ConnectX EN Gigabit Ethernet Cards can support up to 200Gbps data rate. Each ConnectX adapter card, as mentioned above, supports optical transceivers and modules applied for 10G/25G/40G/100G Ethernet network. ConnectX-2 EN Ethernet card, for example, can be used for 10GbE networks. Except the expensive SFP+ optical transceivers, SFP+ DAC Twinax and 10GBASE-T copper cables are the commonly used  transmission media for 10G data center inter-rack and TOR switching. So how to choose between them?
DAC Twinax Cable
DAC SFP+ Twinax cables integrates SFP+ modules and Twinax cables on the same conduit. It uses the SFP+ optical transceiver modules as connectors (not the real transceiver) on both ends so as to provide a cost-effective and low-power consumption solution for data center interconnection. 10G DAC Twinax cables can be divided into two types: active DAC twinax and passive DAC cables. For distances >5m and <10m, pickup the active version. Otherwise passive direct attach copper cables should be fine.
SFP+ DAC Twinax cables in NiC
Fiberstore is one of the best vendors for DAC and other fiber optics. Their packaging and after-sale support for even the smallest orders is excellent. For connecting two ConnectX-2 cards together, you can get one of the SFP+ copper cables.
Ethernet Network Cables
Ethernet Network Cables like Cat5, Cat5e, Cat6 do look alike from the outside and they all use the same connectors as well. However, they have significant differences on the inside. One simple method is that you can find out the type of cable you have by looking at the text printed on the side of the cable. There are other cables possible (like Cat7 and Cat8 cables) but Cat5, Cat5e, Cat6 cables are the most common now.
  • CAT5
Category 5 cabling is an older type of network cabling compared with Cat5e and Cat6 cables. Cat5 cables support transfer speeds of 10/100 Mbit/s (Fast Ethernet). Nowadays, many installers treat it as old and obsolete and try not to use it. For those who buy cat5 cables,  they tend to use in older devices such as an older router or switch.
Category 5 enhanced (Cat5e) cables currently are the most commonly used Ethernet network cables owing to its enhanced transmission data rate and reduced crosstalk. Cat5e cabling supports 1000 Mbit/s and cust down on external and internal crosstalk. It basically means that Cat5e is better at keeping signals on different circuits or channels from interfering with each other.
  • CAT6
Category 6 cabling (Cat6) supports 10 Gbit/s speeds with additional crosstalk improvements. If you're purchasing a new cable for future proofing,  it should really be CAT6 or above. That doesn't imply Cat6 cables protect your network from the future or anything, it just means it will keep it up to date for longer when the next products comes along.
Note : Your network speed depends on  the slowest part of your setup. If you want to deploy gigabit ports, gigabit routers, switches,  then please make sure you cabling also supports those speeds as well.
Mellanox is the world-class vendor for selling multi-protocol chips and adapter cards for servers. It provides a wide range of high-speed interconnection solutions including Gigabit Ethernet cards and InfiniBand adapter cards. The above mentioned ConnectX Gigabit Ethernet cards can not be used in InfiniBand networks. ConnectX Mellanox Gigabit Ethernet cards are the cost-effective devices for your network applications. If you do have the Mellanox NIC cards, you can buy the cost-effective DAC and optical transceiver modules from FS.COM to further reduce the total cost of your budget.

Thursday, April 6, 2017

How to Choose SFP Transceiver Modules for UniFi US-8-150W Switch?

Ubiquiti Networks Unifi switch is part of the UniFi line of products that delivers robust performance and intelligent switching for the growing networks. Many customers nowadays hold great feedback about the cost-effective UniFi switches. US-8-150W, as one of the most popular UniFi switches, offers eight Gigabit RJ45 ports and 2 SFP ports that can support up to 1Gbps. So, how to choose the suitable optics for UniFi US-8-150W switch? This article will provide detailed information about this UniFi switch and the appropriate SFP modules for US-8-150W switch (seen in the below image).
US-8-150W port info
Understanding UniFi US-8-150W Switches
Ubiquiti Networks UniFi switches can be divided into two types: managed Gigabit switches and managed PoE+ Gigabit Switches. In short, POE switches and non-POE switches. Each UniFi switch type is fully managed Gigabit switches with RJ45 and SFP+/SFP ports, offering non-blocking throughout switching performance.
US-8-150W UniFi switch features 8 RJ45 ports and 2 SFP ports which offer convenient different power output options, auto-sensing IEEE 802.3af/at POE/POE + performance. It is a bit larger than a standard home switch. So, would-be buyers who are looking to rack mount need to buy a extra shelf and stick it there. The table below provides the clearer information about this switch.
port info of US-8-150W
Note that US-8-150W is only US $199.
How to Select SFP Modules for UniFi US-8-150W Switches?
According to Ubiquiti Networks, both their original and third party SFP transceiver modules from other vendors can be used on UniFi switches.
Ubiquiti Networks UF-MM-1G & UF-SM-1G-S
Ubiquiti Networks only offer two type of SFPs—UF-MM-1G and UF-SM-1G-S. UF-MM-1G SFP module supports a data rate of 1.25 Gbps over multimode fibers. It uses the 850nm as the Tx and Rx wavelength with a supporting distance of 550m.
UF-SM-1G-S is a single-mode SFP available in both blue (1310nm) and yellow (1550nm) color code. Unlike the 1000BASE-LX SFP optics with LC single-mode fibers that can operate up to 5 km, UF-SM-1G-S only supports a link limit of 3 km.
Ubnt SFP and SFP+ modules
Figure 3 presents all the existing fiber optic transceivers (SFP and SFP+) from Ubiquiti Networks. UF-SM-1G-S is in the middle of the image.
3rd Party SFPs for US-8-150W Switch
Besides the above two SFP types, there are several more Gigabit Ethernet standards for SFP transceiver modules—1000BASE-T, 1000BASE-SX, 1000Base-LX/LH, 1000BASE-ZX, 1000BASE-BX-D, 1000BASE-BX-U and 1000BASE-EX, which are compatible with the UniFi switches. According to the Ubiquiti Networks, Fiberstore (FS.COM) SFPs are tested to be fully compliant with UniFi switches. For more information about these compatible SFPs, please check on the following list.
FS.COM compatible SFPs for UniFi switches
From the table, we know that several Cisco SFP modules and HPE SFP transceivers are working on the UniFi Switches. In our test center, we have tested the GLC-T compatibility and Cisco GLC-SX-MM compatible issues.
More Information About UniFi Switches
Besides the hot selling US-8-150W switches, there are a series of UniFi switches such as US-8-60W, US-16-XG, US-48, US-8, US-24, US-48-750W, US-48-500W, US-24-250W, US-24-500W. Whether you use which one, FS.COM SFPs in the above table are tested to be fully compatible with UniFi switches. For such a low price of the 3rd party SFP transceiver modules, it is advisable for you to purchase more optics for backup.
The UniFi US-8-150W switches are designed to be part of the complete line of small business or home networking and wireless communication products that work together as part of proven, fully integrated, easy-to-use small business solution. UniFi switches support several types of Gigabit Ethernet SFP optical transceivers. All these high-quality fiber optic transceivers can be found on FS.COM for great prices. We also make sure to provide its customers same day shipping. Some of the items can be directly shipped from Seattle warehouse.