Tag Archives: SFP port

Gigabit Slots: SFP Port vs. RJ45 Port vs. GBIC Port

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In Gigabit Ethernet applications, either SFP port, RJ45 port or GBIC port is used in different Gigabit devices, such as switches, routers, servers and storages. And some latest wireless access points (APs) are also equipped with SFP port. Since all these three port types only support 1Gbit and do not go any higher, why are they created instead of using only one type?

RJ45 port and SFP port in an Ethernet switch

SFP Port vs. GBIC Port: An Improvement in Dimension

SFP port and GBIC port can be found in a variety of equipment, including Ethernet switches, routers, network interface cards, servers, etc. Today most Ethernet switches are designed with as least one or two Gigabit SFP uplink slots. What is SFP port? As the name implies, SFP port is intended for taking in SFP (mini-GBIC) fiber modules with small form-factor (SFF) connectors, while GBIC port is for accepting GBIC modules.

GBIC module and SFP module

The two types of ports can provide the same data rates and same distances in Gigabit applications, but the same number of SFP ports uses less space than that of GBIC ports. Since they have the equal functionality, SFP has gradually taken the place of the older GBIC in Gigabit networking for space-saving and economical reasons. The table below is a comparison of SFP port vs. GBIC port.

Parameter SFP Port GBIC Port
Supported Optical Modules SFP transceiver (single-mode/multimode, simple/duplex, CWDM/DWDM) GBIC transceiver (single-mode/multimode, simple/duplex, CWDM/DWDM)
Transceiver Receptacle Type LC, RJ45 SC, RJ45
Supported Standards 1000BASE-T, 1000BASE-SX, 1000BASE-LX, 1000BASE-LX10, 1000BASE-LX/LH, 1000BASE-LH, 1000BASE-EX, 1000BASE-ZX, 1000BASE-BX, 1000BASE-CWDM, 1000BASE-DWDM.
Supported Distances Up to 100 m, 300 m, 2 km, 10 km, 20 km, 40 km, 80 km, 100 km, 150 km.
Module DOM Function Modules support digital optical monitoring (DOM) function, providing real-time monitoring of transceiver’s operation temperature, optical input, optical output, laser bias current and supply voltage.

If you want to know more about the SFP types that the SFP port support and their detailed specifications, such as wavelengths and distances, you can read: How Many Types of SFP Transceivers Do You Know.

SFP vs. RJ45 port: Distance Makes Difference

The RJ45 ports in Gigabit networking devices follow the 1000BASE-T Ethernet standard. They only support twisted pairs for network connections, and the distance is limited to 100 m (330 feet). RJ45 port uses Category 5/5e/6 and higher level copper Ethernet cables for 1Gbit transmission. Compared with switch using only RJ45 port, SFP port switch supports more types of communication cables and longer reaches of links. Here are the differences between SFP vs. RJ45 port.

Parameter SFP Port RJ45 Port
Connection Cable Types Multimode fiber cable, single-mode fiber cable, twisted pairs (Cat5, Cat6 or higher). Twisted pairs (Cat5, Cat6 or higher).
Max. Transmission Distance MMF (550 m), SMF (150 km), Cat5 (100 m) 100 m (330 ft)
Data Rate 1000 Mbps (1G) 1000 Mbps (1G)

Since most end-points at the customer’s are still using RJ45 port, in order to retaining the convenience of RJ45 port while providing the advantage of SFP network to customers, some switches include combo SFP/RJ45 ports. So users can choose to utilize either the SFP port or the RJ45 port at a time for short-distance connections.

What Is Dual-Rate SFP Port?

Unlike the combo SFP/RJ45 port which is actually a link shared by two different ports, a dual-rate SFP port is one single SFP slot that can be configured to support two different data rates. Generally a dual-rate SFP slot can set to be either 1G mode or 10G mode, i.e., an SFP module or an SFP+ module can be installed in it. But the actual data rate of the transmission depends on the mode being settled and the transceiver module being used. There are several cases:

  • The dual-rate SFP slot is 10G activated, and an SFP+ module is installed; the interface is in 10G mode.
  • The port is 10G activated, but an SFP module is installed; the interface is in 1G mode.
  • The port is not 10G activated, but an SFP+ module is installed; the interface will be link down state.
  • The port is not 10G activated, and an SFP module is installed; the interface is in 1G mode.

Summary

The three port types—SFP port, RJ45 port and GBIC port—are used in different networking equipment. The SFP port is now more commonly used than GBIC port since the former one provides the same function and is more compact. When SFP port vs. RJ45 port, SFP port supports connectivity through varieties of fiber cables and the copper twisted pairs, and a wide range of link distances, but RJ45 port accepts only twisted pair cables and a shorter distance. Since every thing has both two sides, it is not always the best to choose SFP slot. The two articles: GBIC vs SFP: When It’s Best to Use GBIC and When to Use SFP, and RJ45 vs SFP: Which Should I Use to Connect Two Switches, specifically discussed when to use which port/module type.


Compatible Cisco 2960 SFP for Cisco 2960 Series Switches

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Cisco Catalyst 2960 series switches are available in 2960, 2960-S, 2960-SF, 2960-X and many other types. The Cisco 2960-S and 2960-SF series are the newest members of the 2960 family that offer a rich set of Layer 2 features. The 2960-S provides Gigabit Ethernet (10/100/1000) connectivity with 10G/1G SFP+ uplinks, and the 2960-SF provides Fast Ethernet (10/100) connectivity with 1G SFP uplinks. This blog mainly introduced the knowledge of 2960-SF series switches and their compatible Cisco 2960 SFP modules.
Cisco 2960
Cisco Catalyst 2960-SF Series Switches Overview
Cisco Catalyst 2960-SF series switches deliver secure and reliable LAN access for branch and medium-sized campus deployments. They enable reliable and secure business operations and lower total cost of ownership through a range of innovative features including FlexStack, Power over Ethernet Plus (PoE+), and Cisco Catalyst SmartOperations. These series switches include 7 models. 5 models with LAN Base Software and 2 models with LAN Lite Software.

Cisco Catalyst 2960-SF Series Switches with LAN Base Software
Switch Model Description Uplinks Available PoE Power
2960S-F48FPS-L 48 Ethernet 10/100 ports with PoE+ 4 SFP 740W
2960S-F48LPS-L 48 Ethernet 10/100 ports with PoE+ 4 SFP 370W
2960S-F24PS-L 24 Ethernet 10/100 ports with PoE+ 2 SFP 370W
2960S-F48TS-L 48 Ethernet 10/100 ports 4 SFP
2960S-F24TS-L 24 Ethernet 10/100 ports 2 SFP
Cisco Catalyst 2960-SF Series Switches with LAN Lite Software
2960S-F48TS-S 48 Ethernet 10/100 ports 2 SFP
2960S-F24TS-S 24 Ethernet 10/100 ports 2 SFP

What’s the Difference Between the LAN Base and LAN Lite Switches?
The Cisco 2960-SF switches support the LAN Base and the LAN Lite software feature sets. The LAN Base feature set comes with advanced Layer 2(L2) features and is typically targeted at large enterprise customers. The LAN Lite feature set has entry-level L2 features and is targeted at mid market deployments. Following are the notable hardware differences:

  • Ease of management with Cisco FlexStack
  • Power of Ethernet (PoE/PoE+) capabilities
  • Increased number of VLANs
  • A wider selection of Small Form-Factor Pluggable (SFP) ports

Compatible Cisco 2960 SFP for Cisco 2960-SF Series Switches
By consulting the Cisco 100-Megabit Ethernet and Gigabit Ethernet SFP Modules Compatibility Matrix, I get following compatible Cisco 2960 SFP models that supported for 2960-SF series switches.

Compatible Fast Ethernet SFP Modules for Cisco 2960-SF Series Switches
Network Device Transceiver Model Description
2960S-F48TS-S

2960S-F24TS-S

GLC-GE-100FX 100BASE-FX SFP 1310nm 2km
GLC-FE-100FX 100BASE-FX SFP 1310nm 2km DOM
Compatible Gigabit Ethernet SFP Modules for Cisco 2960-SF Series Switches
Network Device Transceiver Model Description
2960S-F48TS-S

2960S-F24TS-S

2960S-F48FPS-L

2960S-F48LPS-L

2960S-F24PS-L

2960S-F48TS-L

2960S-F24TS-L

GLC-T 1000BASE-T Copper RJ-45 100m
GLC-TE 1000BASE-T Copper RJ-45 100m
GLC-SX-MM 1000BASE-SX SFP 850nm 550m
GLC-LH-SM 1000BASE-LX/LH SFP 1310nm 10km
GLC-SX-MMD 1000BASE-SX SFP 850nm 550m DOM
GLC-LH-SMD 1000BASE-LX/LH SFP 1310nm 10km DOM
GLC-EX-SMD 1000BASE-EX SFP 1310nm 40km DOM
Network Device Transceiver Model Description
2960S-F48FPS-L

2960S-F48LPS-L

2960S-F24PS-L

2960S-F48TS-L

2960S-F24TS-L

GLC-ZX-SM 1000BASE-ZX SFP 1550nm 70km
GLC-ZX-SMD 1000BASE-ZX SFP 1550nm 70km DOM
GLC-BX-D BiDi SFP 1490nm-TX/1310nm-RX 10km
GLC-BX-U BiDi SFP 1310nm-TX/1490nm-RX 10km
CWDM SFP 1270nm-1610nm (20nm spacing)

Conclusion
Cisco 2960-SF Ethernet switch enables a wide range of business or residential applications and services. FS.COM offers all above Cisco compatible transceiver with reasonable prices and high performance. All those products are tested before shipping to ensure high quality. For more details, please visit www.fs.com or contact us via sales@fs.com.

Related Article: Compatible Transceivers for Cisco Catalyst 4948E Switch

Full CWDM Mux Demux and CWDM SFP Transceivers Solutions

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CWDM systems have channels at wavelengths spaced 20 nanometers (nm) apart, compared with 0.4 nm spacing for DWDM. This allows the use of low-cost, uncooled lasers for CWDM. In a typical CWDM system, laser emissions occur on full eighteen channels at eighteen defined wavelengths: 1610 nm, 1590 nm, 1570 nm, 1550 nm, 1530 nm, 1510 nm, 1490 nm, 1470 nm, 1450 nm, 1430 nm, 1410 nm, 1390 nm, 1370 nm, 1350 nm, 1330 nm, 1310 nm, 1290 nm, 1270 nm. Besides, for CWDM systems an industry standard color coding scheme is used. The latches of the CWDM SFP transceivers match the colored port indicators on the passive units therefore guaranteeing simple setup. Following color codes and wavelength are valid for CWDM.

cwdm-channels

Full CWDM Channels (18 Channels) Mux Demux Solution

The WDM system uses a multiplexer at the transmitter to combine several wavelengths together, each one carry different signal with bite-rate up to 10G and a demultiplexer at the receiver to split them apart. Both mux and demux are passive, requiring no power supply. The 18 Channels CWDM mux demux covers all channels of 1270nm to 1610nm in 20nm increments. Without replacing any infrastructure, it totally support data rates up to 180 Gbps by being completely protocol transparent. The main fields of applications are the use in SDH (STM-1, STM-4, STM-16, STM- 64), IP (Fast Ethernet, Gigabit Ethernet, 10 Gigabit) ATM and storage (1G, 2G, 4G, 8G, 10G Fibre Channel) networks. Connectors, located on the front of the CWDM mux demux modules, are labeled and use the same color-coding that is used to indicate the wavelength of the individual CWDM SFP transceivers (shown in the figure below).

cwdm-mux-demux

When fiber availability is limited, CWDM mux demux could increase the bandwidth on the existing fiber infrastructure. By using 18ch CWDM mux demux mentioned above and the CWDM SFP transceivers, up to 180 Gbps could be supported on a fiber pair.

18-channels-cwdm-mux-demux

Full CWDM SFP Transceivers Solution

CWDM SFP transceiver is based on the SFP form factor which is a MSA standard build. The max speed of this product is 1.25G and they are also available as 2.5G and of course the popular CWDM 10G SFP transceivers. The CWDM SFP transceiver has a specific laser which emits a “color” defined in the CWDM ITU grid. The CWDM ITU grid is defined from 1270 to 1610nm and has steps of 20nm. So the available wavelength is 1270nm, 1290nm, 1310nm, 1330nm, 1350nm, 1370nm, 1390nm, 1410nm, 1430nm, 1450nm, 1470nm, 1490nm, 1510nm, 1530nm, 1550nm, 1570nm, 1590nm and C. Besides, our CWDM SFP transceivers are similarly color-coded as the CWDM mux demux to help you match the right link connection (shown in the figure below).

CWDM SFP

We can make the CWDM SFP transceivers compatible with every brand (Cisco, HP, H3C, Juniper, Huawei, Brocade, Arista). A lot of brands have vendor locking and only with the proper coding. Fiberstore is specialized in this rebranding or recoding. We have many different switches and routers in our test lab to test the coding. We also use different Optical Spectrum Analyzers to ensure the CWDM SFP transceiver is emitting the right color and has the correct power budget. The CWDM SFP transceiver is used in combination with passive CWDM mux demux, and we can provide you a complete solution and advice on which equipment fits best in your project. Please give us your project details and we will provide the most efficient and economical solution.

1270nm SFP 1290nm SFP 1310nm SFP 1330nm SFP 1350nm SFP 1370nm SFP
1390nm SFP 1410nm SFP 1430nm SFP 1450nm SFP 1470nm SFP 1490nm SFP
1510nm SFP 1530nm SFP 1550nm SFP 1570nm SFP 1590nm SFP 1610nm SFP

Can I Use SFP Transceiver in SFP+ Slot?

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A common confusion about SFP and SFP+ compatibility is that if I can use the SFP module in SFP+ slot. When I connect the SFP transceiver to SFP+ transceiver, can SFP+ negotiate down to 1G? Or is it possible to use SFP+ module in the SFP port on my switch? Can SFP+ copper twinax cable can negotiate down to 1G to support SFP? Can 1G and 10G can exist in the same link? All these questions usually create a giant headache for many engineers. After looking up many relevant documentation, now I will conclusion the answers in this article.

SFP Can be Plugged into SFP+ Ports in Most Situations
I’m not sure about the specific switch model, but as a general rule of thumb, SFPs will work in SFP+ slot, but SFP+ optics do not work in SFP slots. It’s just a power availability thing. When you plug the SFP module in SFP+ port, the speed of this port is 1G not the 10G. And sometimes this port will lock the speed at 1G until you reload the switch or do some fancy set of commands. Besides, the SFP+ port usually can never support speed under 1G. That is to say, we can’t plug the 100BASE SFP in the SFP+ port. In fact, for this question, it may depend greatly on the switch models – sometimes SFPs are supported in SFP+ ports, and sometimes not. For example, almost all SFP+ ports of Cisco switch can support SFPs and many SFP+ ports of Brocade switch only support SFP+. Though it’s feasible often, it’s safer to ask your switch vendor for some information.

SFP module in SFP+ port

SFP+ Can’t Auto-negotiate Down to 1G to Support with SFP Module
To my knowledge, unlike copper SFPs which are available in 10/100/1000 auto-negotiation, optics such as SFP and SFP+ do not support auto negotiation at all. In fact, Most (95+%) SFPs and SFP+s will only run at the rated speed, no more, no less. Besides, there is no such thing as a SFP+ that does 1G on one side (towards the fiber) and then does 10G on another side (towards the unit). Though we can use SFP in SFP+ ports in many cases, that doesn’t mean a SFP+ plugged into the SFP+ slot can support 1G. In a fiber link, if we plug a SFP in the SFP+ port on one side (1G), and then plug a SFP+ in the SFP+ port on the another side (10G), this may not work! You just can’t have 10 GbE at one end and 1 GbE at the other. For this question, if you use SFP+ copper, it also can’t negotiate down to 1G.

When use SFP and SFP+ modules in your network, make sure the speed of both ends of the fiber link is the same. SFP modules may can be used in SFP+ slot, but a SFP can never be connected to a SFP+ module. For their different speeds, transmission distance and wavelength. 10 SFP+ only can use for 10G SFP+ port, and can never auto-negotiate to 1G.

Related Article: Can I Use the QSFP+ Optics on QSFP28 Port?

Related Article: SFP Module: What’s It and How to Choose It?

Related Article: Understanding Video SFP Transceivers

What Is The Difference: SFP vs SFP+

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As we know, a SFP module just looks the same as the SFP+ module. And most switches can both support SFP module and SFP+ module. So, do these two modules really refer to the same one? What’s the difference between SFP vs SFP+?

SFP vs SFP+

SFP vs SFP+: SFP Definition
SFP stands for Small Form-factor Pluggable. It is a hot-pluggable transceiver that plugs into the SFP port of a network switch and supports SONET, Gigabit Ethernet, Fibre Channel, and other communications standards. SFP specifications are based on IEEE802.3 and SFF-8472. They are capable of supporting speeds up to 4.25 Gbps. Due to its smaller size, SFP replaces the formerly common gigabit interface converter (GBIC). Therefore SFP is also called Mini-GBIC. By choosing different SFP module, the same electrical port on the switch can connect to different fiber types (multimode or single-mode) and different wavelengths.

SFP module Cisco

SFP vs SFP+: SFP+ Definition
Since SFP supports only up to 4.25 Gbps, SFP+ that supports data rates up to 16 Gbps was later introduced. In fact, SFP+ is an enhanced version of the SFP. The SFP+ specifications are based on SFF-8431. In today’s most applications, SFP+ module usually supports 8 Gbit/s Fibre Channel, 10 Gigabit Ethernet and Optical Transport Network standard OTU2. In comparison to earlier 10 Gigabit Ethernet XENPAK or XFP modules, SFP+ module is smaller and becomes the most popular 10 Gigabit Ethernet module in the market.

SFP+ module Cisco

SFP vs SFP+
Review the SFP and SFP+ definition mentioned above, we can know that the main difference between SFP and SFP+ is the data rate. And due to different data rate, the applications and transmission distance is also different.

Ethernet Application

SFP (1Gbps) SFP+ (10Gbps)
1000BASE-SX SFP 850nm 550m

1000BASE-LX/LH SFP 1310nm 20km

1000BASE-EX SFP 1310nm 40km

1000BASE-ZX SFP 1550nm 80km

10GBASE-SR SFP+ 850nm 300m

10GBASE-LRM SFP+ 1310nm 220m

10GBASE-LR SFP+ 1310nm 10km

10GBASE-ER SFP+ 1550nm 40km

10GBASE-ZR SFP+ 1550nm 100km

Fiber Channel Application

SFP (2G, 4G) SFP+ (8G)
2.125Gbps:

2G Fibre Channel SFP 1310nm 2km/15km/20km/40km

2G Fibre Channel SFP 1510nm 80km

4.25Gbps:

4G Fibre Channel SFP 850nm 150m

4G Fibre Channel SFP 1310nm 5km/10km/15km/20km

8.5Gbps:

8G Fibre Channel SFP+ 850nm 150m

8G Fibre Channel SFP+ 1310mn 10km/20km/40km

8G Fibre Channel SFP+ 1510nm 80km

SONET/SDH Application

SFP (155Mbps, 622Mbps, 2.5Gbps) SFP+ (10G)
155Mbps:

OC-3/STM-1 1310nm 2km/15km/40km

OC-3/STM-1 1510nm 80km

622Mbps:

OC-12/STM-4 1310nm 500m/2km/15km/40km

OC-12/STM-4 1510nm 80km

2.5Gbps:

OC-48/STM-16 1310nm 2km/15km/40km

OC-48/STM-16 1510nm 80km

OC-192/STM-64 850nm 300m

OC-192/STM-64 1310nm 2km/10km/20km/40km

OC-192/STM-64 1510nm 80km

As we’ve explained the difference of SFP vs SFP+. Usually, SFP module plugs into SFP port of the switch and SFP+ module plugs into SFP+ port of the switch. But, sometimes SFP module can also be plugged into SFP+ port. Which SFP or SFP+ module should you choose all depends on your switch types. Fiberstore is a reliable SFP transceiver module manufactures, all SFP module and SFP+ module types are available in FS.COM. Besides, SFP+ cable is also provided. What’s more, the price of SFP module and SFP+ module is lower than many other manufactures. SFP test is strict in FS.COM. Matching fiber patch cable is also available.

Related Article: Compatible SFPs for Ubiquiti EdgeSwitch and UniFi switch

Related Article: SFP Module: What’s It and How to Choose It?

Related Article: Understanding Video SFP Transceivers