Category Archives: Network Switches

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

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In Gigabit Ethernet applications, either SFP (small form-factor pluggable) port, RJ45 port or GBIC (Gigabit interface converter) 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 Port 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 port and 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.

Five Common Parameters about Buying PoE Switch

A PoE switch (Power over Ethernet) is a network switch that carries data along with power over Ethernet network cables like Cat5 or Cat6. And PoE switch is often found in IP camera systems in home or business networks due to its low maintenance costs, less downtime, easy installation, etc. Since there are various articles telling you how to buy a PoE switch, here I just explore five parameters as a reference when buying PoE switch. No matter buy 8-port, 16-port, 24-port PoE gigabit switch, the following five parameters are necessary to consider.

PoE-switch, PoE switch gigabit

Switch Stacking

Switch stacking is a common technology in network design. It offers a good solution for network designers to maximize scalability and optimize performance of networks at the same time. Therefore, when it comes to buying gigabit PoE switch, many users will take this parameter into consideration. But not all PoE switches are created equal. Most Cisco PoE switches support stacking. That’s one reason why Cisco PoE switches are more popular than others even if their price is several times higher than other similar PoE switches. However, if buying PoE switch for home or small size networks, there is no need to seek for stacking functions by spending extra money.

Acoustic Noise from Fan

Since PoE switches, especially 8-port, 16-port, and even 24-port PoE switch, are often used at home or office, the acoustic noise can be placed an important role when buying PoE gigabit switch. Because it’s really a bad experience if the PoE switch near to you is buzzing all the time. Different PoE switch comes with different acoustic value. Still take Cisco 24-port PoE switch SFE2000P as an example. This 24-port PoE gigabit switch may cause 50dB noise at the maximum, which like a person speaking to you without stopping. Of course, many vendors like FS.COM and Cisco, have supplied fanless PoE switch to offer a better usage experience for users.

Transmission Distance

In some applications, administrators have to deploy PoE switch up to 250m. Generally speaking, PoE switches can extend the transmission distance of data and power up to 100m via Cat5 or Cat5e network cables, which is enough for home or office applications. In this condition, a PoE repeater can deal with it perfectly. With one PoE repeater, the transmission distance can be added to 100 meters.

Numbers of Power Supply

In the PoE gigabit switch market, there are two types power supplies: a single power and dual power. Usually dual power is designed for power redundancy. When one of the DC power inputs has failed, the other will be triggered and working for the switch. Does it mean dual power is necessary for PoE switch? May not be. Considering the power redundancy, most vendors have strengthened their switch power supply, which can support the switch working for years. And some switches like Cisco catalyst 3850 series PoE switches offer dual power supplies, but it requires extra order to get it working.

Airflow Direction

This factor is often considered by those who have or work in data centers or service room where have numbers of network switches. Generally there are three types of airflow of network switch: back-to-front, front-to-back and side-to-side. Keep in mind to consider this factors when buying a PoE switch, especially buy 48-port PoE gigabit switches that are often used for enterprise networks. There are examples in tech forum that some users ignore the airflow direction of the network switch, which causes the switch fans drawing air from its hot air exhaust.

Summary

Buying a suitable PoE switch is not an easy task. Both the switch price and functions are needed to be taken into consideration. FS.COM offers PoE managed switches with different ports like 8-port, 24-port and 48-port. All of them are compatible with IEEE802.3af/at. And professional buying advice is also provided if need. Welcome to visit www.fs.com for more details.

Related article: PoE Switch VS. PoE+ Switch, Which Will You Choose?

Smart Switch: A Wise Choice for SMB Networks

Ethernet network switch marks the backbone of your enterprise network, with which you can connect multiple core devices like routers, printers, PCs and other hardware. There exist a dazzling array of network switches with various feature sets and functions. With regard to management options, there are primary three categories of switches: unmanaged switch, smart switch and managed switch. Among which smart switch has ranked as a moderate choice for better regulating business network – as a perfect mix of essential functions and affordability. If you’ve outstripped your unmanaged switch but don’t expect for a more advanced managed switch, it’s the right time to consider a smart managed switch.

What Is A Smart Switch?

Smart switch, or smart managed switch, fills the middle ground between the unmanaged switch and managed switch – it offers certain levels of management, basic quality-of-service (QoS) and limited security features with limited numbers of ACLs (access control lists) . Smart switch generally has a browser-based interface for management and it also enable segmentation of the network by creating VLANs, which makes it quite a versatile solution. Smart switch fits best at the edge of a large network (with managed switches as core switch). Here we make a further comparison between smart managed switch vs unmanaged switch, and smart switch vs managed switch.

smart switch

Smart Switch vs Unmanaged switch

Unmanaged switch presents the most cost-friendly plug-and-play solution for deployment that require only basic layer 2 switching and connectivity. It cannot be modified/managed and requires no configuration at all. Primarily targeted for home and SOHO, unmanaged switch is generally used to small network with only a few components, or to add temporary workgroups to larger networks. Compared to “dumb” unmanaged switch, smart managed switch opens the door to manage, monitor and configure the network, but only with very limited capability.

smart switch vs unmanaged switch

Smart Switch vs Managed Switch

Fully managed switch is designed to deliver the most comprehensive set of features to provide the highest level of security, the most precise control and management and the greatest scalability. Managed switch can be deployed as aggregation/access switches in very large professionally networks or as core switches in relatively smaller networks, allowing organizations to manage and troubleshoot network remotely and securely, and to expand with flexibility.

smart switch vs managed switch

Smart switch can be seen as a “lighter” managed switch – less capable and scalable than the managed switches, with lighter management capabilities and less VLAN groups and nodes (mac address). As such, smart switch offers a less expensive alternative to managed switches. Additionally, managed switch generally allows for full configuration by command line interface (CLI) via a console port and telnet and or SSH session, and often a web GUI. While a smart switch often lacks any console port, have less configuration flexibility via a web-based interface. Seen as an entry-level managed switch.

Should I Choose Smart Switch Over the Other Two?

The choice typically depends on two factors: budget and application. If you just want to setup a home network and keep things simple, an unmanaged and smart managed switches are good enough. But if you want to manage a LAN and need configuration options like VALN and QoS, or to deal with mission-critical applications that demands massive data traffic, it is better to use at least a smart managed switch or the more powerful managed switch.

As unmanaged switch is targeted for home and SOHO while fully managed switch for data centers, enterprises and relatively professional networks, smart switch, therefore, is mostly for small to medium sized business (SMB) users who may need some or certain configuration and management. They offer access to switch management features such as port monitoring, link aggregation, and VPN through a simple Web interface.

Conclusion

We have gone through the basics of three primary categories of network switch – unmanaged switch, smart switch and fully managed switch, as well as deployment scenarios of each. Smart managed switch can make an excellent transition solution when unmanaged switch is never adequate and the cost for a managed switch cannot be justified. Organizations and enterprises nowadays have reap significant benefits from using smart managed switch, which proves that it is a journey worthwhile to take, especially for SMB networks.