Powering PoE Switch From A PoE Switch: Is It Possible?

PoE (Power Over Ethernet) technology supports power and data transmission over the same Ethernet cable, which makes the cabling easier and greatly saves the space. Characterized by this advantage, PoE switch gains the popularity among many users. In practical application, we may meet some emergency, such as power failure. At this time, is powering PoE switch from a PoE switch possible? This article will discuss this topic.

Working Principe of PoE Switch

Before we come to the answer of powering PoE switch from a PoE switch, let’s learn about working principle of PoE switch. A whole PoE system consists of Powering Sourcing Equipment (PSE) and Power Device (PD). PoE switch is a type of PSE device. The PSE device not only powers Ethernet client devices, but also manage the entire Power over Ethernet process. While the PD device is PSE load which receives power, or we can call it PoE system client. The working principle pf PoE switch can be divided into five steps. For applications of PoE switch, you can read this article: Using PoE Switch for Different IP Camera Systems

Detection: PoE switch outputs very small voltage on the port, until it detects that the PD equipment connected to the cable end supports the IEEE802.3af standard.

PD Classification: After detecting the PD, PoE switch may classify PD equipment, and assess the power loss of PD equipment.

Begin to Supply Power: In a configurable time (usually less than 15μs) start-up period, PoE switch begin to power PD equipment with low voltage, until it provides 48V DC power supply.

Power Supply: PoE switch provide stable and reliable 48V DC power for PD equipment to meet the power consumption which is less than 15.4W.

Power Off: If the PD equipment is disconnected from the network, the PoE switch will stop powering the PD equipment quickly, generally within 300-400ms, and repeat to detect whether the end of the cable is connected to the PD equipment.

Powering PoE Device From A PoE Switch

PoE switch is self-adaptive. When the PSE has the power supply requirement, the PD will output the voltage to the PSE. This means the switch can be powered by PoE while simultaneously providing power by PoE to other devices such as IP phones or wireless access points. This provides great flexibility because it means that the switch can be deployed without the constraints of an AC power outlet. As for powering PoE switch from a PoE switch, Universal PoE (UPOE) technology will be required and the following part will talk about UPOE. The following figure shows the evolution of PoE technology.

Evolution of PoE Standard

Powering PoE Switch From A PoE Switch with UPOE Technology

UPOE technology is a new innovation from Cisco Systems which happens to the industry’s first 60-watt Power over Ethernet technology. It can offer twice the power per port of the switch—providing both power and network access to a greater range of devices through a single standard Ethernet cable. This can surely help to lower the total cost of IT operations. By using UPOE technology, powering PoE switch from a PoE switch is possible. Here is an example to help you have a better understanding of this.

Most major networking vendors provide PoE Passthru, but they all require using higher powered sources. It physically would be impossible otherwise. If X is the power provided to the switch and Y is the power the switch uses, then Z is the power available for PoE devices. Then X – Y = Z. If you want Z to meet the PoE specification, then X has to be at least: Z + Y which means your input power needs to be UPOE.

Conclusion

As the enterprise workspace evolves with more and more end devices for communication, collaboration, security, and productivity, the need of PoE is also evolving to support newer end devices with increased power requirements. Regarded as upgrade of PoE, UPOE technology doubles the power delivered per port over PoE+ to 60 Watts which can extend resilient network power to a broad range of devices. What’s more, it realizes powering PoE switch from a PoE switch.

Introduction to 48 Port Gigabit SFP Switch

As we all know, data center cabling system consists of multiple devices, such as fiber optic transceiver, fiber optic patch cable, fiber patch panel, cable manager, and so on. As the central nerve of the whole cabling system, gigabit switch has been a topic of discussion. To satisfy different sizes of networking deployment, there are various types of Ethernet switches. This article will introduce a kind of 48 port gigabit SFP switch.

Overview of 48 Port Gigabit SFP Switch

FS.COM S5800-48F4S switch is a 48 port gigabit switch with 10gb uplink. It has 48×1GbE SFP ports and 4×10GbE SFP+ ports in a compact 1RU form factor. The switching capacity of this 48 port switch is 176 Gbps and its non-blocking bandwidth is 88 Gbps. And this gigabit switch can provide 130.95 Mpps. Meanwhile, FS.COM S5800-48F4S switch has 2 (1+1 redundancy) hot-swap power supplies and 4 (N+1 redundancy) hot-swappable fans. It is also a low latency L2/L3 Ethernet switch with 2.3us latency. The price of this 48 port gigabit switch with 10gb uplink is US$ 1,699.00. Here is a figure for you which shows front and back panel overview of FS.COM S5800-48F4S 48 port gigabit SFP switch.

front and back panel overview of 48 port gigabit SFP switch

Highlights of 48 Port Gigabit SFP Switch

The S5800-48F4S 48 port gigabit SFP switch with 10GE SFP+ uplinks comes with the complete system software with comprehensive protocols and applications to facilitate the rapid service deployment and management for both traditional L2/L3/MPLS networks. With support for advanced features, including MLAG, SFLOW, SNMP etc, this switch is ideal for traditional or fully virtualized data center. The S5800-48F4S hardware also provides high-availability features, including pluggable redundant fans and using high quality electronic components, which ensures low power consumption.

Applications of 48 Port Gigabit SFP Switch

Designed with 48×1GbE SFP ports and 4×10GbE SFP+ ports, FS.COM S5800-48F4S 48 port gigabit SFP switch can accomplish N×1G to N×1G (N≤48) connection or N×10G to N×10G (N≤4) connection. For example, in 5G to 5G connection, on one side, five 1G SFP transceivers are plugged into SFP ports on S5800-48F4S switch; on the other side, another five 1G SFP transceiver modules are plugged into SFP ports on switch, too. Then, these five SFP optical transceivers are connected by five fiber optic cables. It should be noted that the transceivers and fiber patch cables used in the link are of the same type.

Supported Accessories for 48 Port Gigabit SFP Switch

In the above part, we mention that the S5800-48F4S 48 port gigabit SFP switch can be used with SFP transceiver, SFP+ module and fiber optic cable. This part will go on introducing some support accessories for this 48 port gigabit SFP switch.

Fiber Optic Transceiver
ID Type Wavelength Transmission Distance Interface DOM Support
29838 1000BASE-SX SFP 850 nm 550 m over OM2 MMF LC duplex, MMF Yes
20057 1000BASE-T SFP 100 m over Cat5 RJ45 No
29849 1000BASE-LX/LH SFP 1310 nm 10 km LC duplex, MMF/SMF Yes
11591 10GBASE-LR SFP+ 1310 nm 10 km LC duplex, SMF Yes
11589 10GBASE-SR SFP+ 850 nm 300 m over OM3 MMF LC duplex, MMF Yes
Cable
ID Cable Length Connector Type Fiber Count Polish Type Jacket Material
21278 2 m SFP+ to SFP+ Passive Copper Cable (DAC) PVC (OFNR)
35194 3 m SFP+ to SFP+ Passive Copper Cable (DAC) PVC (OFNR)
40191 1 m LC to LC OS2 Duplex UPC to UPC PVC
40192 2 m LC to LC OS2 Duplex UPC to UPC PVC
41730 1 m LC to LC OM3 Duplex UPC to UPC PVC
40180 1 m LC to LC OM4 Duplex UPC to UPC PVC
CWDM MUX DEMUX
ID Wavelength Channel Spacing Channel Bandwidth Line Type Client Port Special Port
33489 18 channels 1270-1610nm 20 nm ±6.5nm Dual fiber Duplex LC/UPC Monitor Port
43099 8 Channels 1470-1610nm 20 nm ±6.5nm Dual fiber Duplex LC/UPC Expansion Port

Conclusion

As the size of data center becomes larger and larger, cable density increases, too. To simplify the cabling, many data center managers prefer network switch with high density ports. The above 48 port gigabit SFP switch with 10GE SFP+ uplinks is a suitable choice for high density cabling.

Different Types of Switches in Networking

For networking builders, network switch is an essential component in their networking building plan. In a network deployment, switch channels incoming data from any of multiple input ports to the specific output port that will take the data toward its intended destination. Besides, to achieve high performance level, there are different types of switches in networking. This article will introduce different types of switches in networking to help you choose a suitable one for your networking.

LAN Switch

Local area network switches or LAN switches are usually used to connect points on a company’s internal LAN. It is also known as a data switch or an Ethernet switch. It blocks the overlap of data packets running through a network by the economical allocation of bandwidth. The LAN switch delivers the transmitted data packet before directing it to its planned receiver. These types of switches reduce network congestion or bottlenecks by distributing a package of data only to its intended recipient.

Unmanaged Switch

Unmanaged network switches are frequently used in home networks, small companies and businesses. It permits devices on the network to connect with each other, such as computer to computer or printer to computer in one location. An unmanaged switch does not necessarily need to be configured or watched. It is simple and easy to set up. If you want to add more Ethernet ports, you can use these plug and play types of switches in networking.

Managed Switch

Compared to unmanaged switches, the advantage of managed switches is that they can be customized to enhance the functionality of a certain network. They offer some features like QoS (Quality of Service), Simple Network Management Protocol (SNMP) and so on. These types of switches in networking can support a range of advanced features designed to be controlled by a professional administrator. In addition, there is smart switch, a type of managed switch. It has some features that managed switch has, but are more limited. Smart network switch is usually used for the networking devices such as VLANs.

PoE Switch

PoE Gigabit Ethernet switch is a network switch that utilizes Power over Ethernet technology. When connected with multiple other network devices, PoE switches can support power and data transmission over one network cable at the same time. This greatly simplifies the cabling process. These types of switches in networking provide greater flexibility and you will never have to worry about power outlet when deploying network devices.

 PoE-Gigabit-Switch

Stackable Switch

Stackable switches provide a way to simplify and increase the availability of the network. For example, instead of configuring, managing, and troubleshooting eight 48-port switches individually, you can manage all eight like a single unit using a stackable Switches. With a true stackable switch, those eight switches (total 384 ports) function as a single switch—there is a single SNMP/RMON agent, single Spanning Tree domain, single CLI or Web interface. There are valuable operational advantages to use these types of switches in networking, such as you can create link aggregation groups spanning across multiple units in the stack, port mirror traffic from one unit in the stack to another, or setup ACLs/QoS spanning all the units.

Conclusion

This article briefly introduces five types of switches in networking: LAN switch, unmanaged switch, managed switch, PoE switch and stackable switch. All of them have their own characteristics and are used in different network deployment. I hope you can have a better understanding on them after reading the article.

Gigabit Switch Review: Ethernet Switches Recommendations

Ethernet switches, also known as network switches, serve as the brain of the whole network, especially for data center. On the market, there are various types of Ethernet switches which are designed for different requirements, such as port number, speed, managed or unmanaged. Faced with so many choices, you may get confused about which one is the best switch. In fact, not just you, there are a lot of people who don’t know how to make the choice. In the year 2017, Gigabit switch has been the hot topic at several big forums, and the question “Can you recommend a Gigabit switch for me?” frequently occurred. This article will focus on Gigabit switch review and recommend several Ethernet switches for you.

Gigabit Switch Review 1: D-Link DGS-1008G Gigabit Switch

D-Link DGS-1008G Gigabit switch has eight gigabit ports and boasts data transfer speeds of up to 2000 Mbps. It comes with QoS features, which automatically organize and prioritize important and time-sensitive data packets, ensuring efficient delivery. This feature helps enable smoother media streaming, VoIP calling and online gaming features. In addition, it utilizes D-Link’s Green Technology which allows the switch to reduce heat and use less energy. D-Link DGS-1008G Gigabit switch is a solid choice if you are looking for a fast, easy-to-use and reliable network switch.

Gigabit Switch Review 2: FS S5800-8TF12S Managed Switch

FS S5800-8TF12S switch is a 12 port smart managed switch. It is designed with twelve 10G SFP+ ports and eight 1000BASE-T/ SFP combo ports. The 1000BASE-T copper RJ45 ports support Gigabit speeds over Cat6 cable up to 100 meters, and the 1G SFP fiber ports can be connected to other devices via SFP transceivers over fiber optic cable. FS S5800-8TF12S 12 port smart managed switch is designed to support a demanding and dynamic environment of SMB networks. It is a good choice for 10G access Layer switch for hyper-converged infrastructure.

Gigabit Switch Review: FS-S5800-8TF12S 12-port smart managed switch

Gigabit Switch Review 3: UniFi US-24-500W PoE Switch

UniFi US-24-500W switch is a 24 port PoE switch which comes with 24 Gigabit RJ45 ports and 2 SFP ports. Its non-blocking throughput is up to 26 Gbps and the switching capacity is up to 52 Gbps. UniFi US-24-500W PoE switchh is a fully managed Gigabit switch which can deliver robust performance and intelligent switching for networks. Besides, it offers the forwarding capacity to simultaneously process traffic on all ports at line rate without any packet loss. It is really a cost-effective PoE switch at $399.00. For more details about Gigabit PoE switch review, you can read my previous article: 8 Port PoE Switch Recommendations.

Gigabit Switch Review 4: FS S5850-48T4Q 10GBASE-T Switch

FS S5850-48T4Q 10GBASE-T copper switch is a 1U managed L2/L3 Ethernet switch. It has forty-eight 10GBASE-T RJ45 ports and four 40G QSFP+ ports. And it can provide 1.28Tbps switching capacity. FS S5850-48T4Q switch is designed to meet next generation Metro, Data Center and Enterprise network requirements. For example, it can be used for Spine-Leaf network which is a popular architecture design for data center. For 1GBASE-T copper switch at lower cost, FS S5850-48T4Q switch is a great option to help you migrate to 10GbE network.

Conclusion

The above content Gigabit switch review has recommend 8 port unmanaged Gigabit switch, 12 port 10G smart managed switch, 24 port PoE switch and 48 port 10GBASE-T copper switch. All of them are good choices when compared with the same type of Ethernet switches. I hope this article can help you choose the best switch when you feel confused.

Uplink Port Vs. Normal Port on Switch

When it comes to network switch, we usually ask about the port type on the switch and the number of port, such as twenty-four 10/100/1000 Mbps ports and four SFP+ ports. If you have used managed switch in your network deployment, you must have heard about uplink port or normal port. How much do you know about them? Is there any difference between them? This article will guide you to learn about uplink port vs. normal port on switch.

Uplink Port Vs. Normal Port: Connect to Different Devices

The uplink port on switch is used to connect a device or smaller local network to a larger network, or connect to the next “higher” device in the topology. For example, edge switch connects “up” to distribution layer managed switch. Also in computer network, hub, unmanaged switch and router typically designate one Ethernet port as the uplink port. And it may be labeled WAN or Internet instead of uplink. This type of port simplify connects different types of Ethernet devices to each other, such as when linking a local home network to a modem and the Internet. While normal port on switch is used to connect end user PC or server and all. In most cases, uplink ports have more bandwidth as compared to normal ports as they aggregate traffic between different layers.

Uplink Port Vs. Normal Port: Connect to Different Cables

Each Ethernet interface has two transmit pins and two receive pins. To achieve the link connection, the transmit pins at one end of network cable have to be connected to the receive pins at the other end. An uplink port does not crossover the transmit and receive pins, but a regular port does. Therefore, when two network switches are connected together with a straight-through cable, then one end must be uplink port and one end must be normal port. If a crossover cable is used to connect them, then the ports at both ends must be the same kind of port. Here is a figure for you to have a better understanding of this.

uplink port vs. normal port

Uplink Port Vs. Normal Port: Additional Information about Shared Port and Dual-purposed Port

Some older network equipment specially configured a normal port next to the uplink port and linked the two together as a pair. Specifically, the hardware logic of these products supported connections to either the uplink port, or the normal shared port, but not both. Connecting devices to both ports of a shared port device stops the unit from functioning properly. Nowadays, many network equipment offer a dual-purpose port which can function either as an uplink or a normal port depending on the type of device connected to it.

Conclusion

In fact, uplink port can serve as normal port. Therefore, there are no big differences between them. The only difference is that uplink port is connected to higher layer network device to aggregate the bandwidth and must be connected to the normal port on another network device. I hope after reading this article, you can be clear on uplink port vs. normal port on switch.