OpenvSwitch vs OpenFlow: What Are They, What’s Their Relationship?

As software defined networking (SDN) becomes popular in high-bandwidth and dynamic applications (for example, cloud computing), related terms such as OpenvSwitch and OpenFlow are talked a lot by IT technicians. Though they have been introduced for a while, OpenvSwitch and OpenFlow still confuse people in some aspects. And the most frequently asked question is what’s the relationship and difference between OpenvSwitch and OpenFlow. Here we will cover these topics on what is OpenvSwitch, what is OpenFlow, and OpenvSwitch vs OpenFlow.

OpenvSwitch vs OpenFlow: OpenFlow Tutorial

Traditionally, networking hardwares from different vendors often have special configuration and management systems, which limits the interacting between routers and switches from different manufacturers. To solve this, OpenFlow is created as an open programmable network protocol for configuring and managing Gigabit network switches from various vendors. It enables us to offload the control plane of all the switches to a central controller and lets a central software define the behavior of the network. Thus network administrators can use OpenFlow software to manage and control traffic flow among different branded switching equipments.

OpenvSwitch vs OpenFlow: How OpenFlow Works
How OpenFlow Works

How Does OpenFlow Work?

OpenFlow generally consists of three components: OpenFlow controller, OpenFlow protocol and a chain of flow tables set up on the OpenFlow switch (as shown above). The OpenFlow protocol is like a media for the controller talking securely with OpenFlow switch. The OpenFlow controller can set rules about the data-forwarding behaviors of each forwarding device through the OpenFlow protocol. Flow tables installed on the switch often stores a collection of flow entries. So when a data packet arrives at the OpenFlow switch, the switch will search for matched flow entries in the flow tables and executes corresponding actions. If no match is found, an inquiry event will sent to the OpenFlow controller which then responds with a new flow entry for handling that queued packet.

OpenvSwitch vs OpenFlow: OpenvSwitch Tutorial

OpenvSwitch, sometimes abbreviated as OVS, is an open-source OpenFlow switch that works as a virtual switch in the virtualized environments such as KVM. It also used as a multilayer software for interconnecting virtual devices in the same host or between different hosts. Currently, OpenvSwitch can run on any Linux-based virtualization platform, which includes: KVM, VirtualBox, Xen, Xen Cloud Platform, XenServer.

OpenvSwitch vs OpenFlow: OpenvSwitch architecture
OpenvSwitch Architecture

OpenvSwitch has eight core elements: ovs-vswitchd, Linux kernel module, ovsdb-server, ovs-dpctl, ovs-vsctl, ovs-appctl, ovs-ofctl, and ovs-pki. Ovs-vswitchd is a daemon that implements the switch. Linux kernel module is for flow-based switching. Ovsdb-server is a lightweight database server. Ovs-dpctl is a tool for configuring the switch kernel module. Ovs-vsctl is a utility for querying and updating the configuration of ovs-vswitchd. Ovs-appctl is a utility that sends commands to running Open vSwitch daemons. Ovs-ofctl is a utility for controlling the OpenFlow features of OVS. Ovs-pki is a utility for creating and managing the public-key infrastructure.

OpenvSwitch vs OpenFlow: What’s Their Relationship?

OpenvSwitch and OpenFlow are both used for SDN application. OpenFlow is one of the first SDN standards. OpenvSwitch is an OpenStack SDN component. As to their relationship, OpenvSwitch is one of the most popular implementations of OpenFlow. Apart from OpenFlow, OpenvSwitch also supports other switch management protocols such as OVSDB (Open vSwitch Database Management Protocol).

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Rack Cable Manager for Data Center Cable Management

As plenty of devices and cables are added into data center cable racks, cable management in racks becomes one of the most pressing challenges for data center managers. To avoid rack cables looking like messy spaghetti, rack cable manager has long been an ideal solution to keep rack cables properly organized. But there are so many kinds of rack cable managers in the market, do you know which one to use for a specific situation? Here discusses some popular rack cable managers and their respective applications.

Cable Management Sections for A Rack

To better understand different kinds rack cable managers, we’d better to know the four cable management sections of a rack. Which are horizontal cable management, vertical cable management, inside of the rack cable management and top of the rack cable management. Horizontal cable managers and vertical cable managers are used for horizontal and vertical cable managements respectively, while copper/fiber patch panels and fiber raceway systems are for inside and top of the racks. The following parts will introduce various cable organizer for these four cable management sections.

Horizontal Rack Cable Manager

Horizontal rack cable manager is often used to manage cables in the front of racks and draw cables away from equipment neatly. It is usually one or two rack units high. Now there are many types of horizontal rack cable managers in the market, which are mainly divided into finger duct rack cable manager, D-ring horizontal cable manager and horizontal cable manager with brush strip. Among them, finger duct rack cable manager offers fingers and pass-through holes for routing rack cables and reducing cable strains, D-ring cable manager provides an “open” and efficient way to manage cables, brush strip manager is mainly used for allowing cables to be passed from the front to the rear of the rack. For more information on these three rack cable managers, read Selecting the Right Horizontal Cable Manager.

horizontal rack cable manager types

Horizontal Rack Cable Manager Types

Vertical Rack Cable Manager

Vertical rack cable managers are used for providing vertical pathways for cable bundles in the rack. Now the common types of vertical rack cable managers are D-ring vertical cable manager, vertical cable manager with bend radius fingers, and open frame rack vertical cable managers. The first one is a cost-effective solution for organizing and routing cable bundles. The second one is designed to maintain cable bend radius effectively. And the last one is available in single-sided and dual-sided models, which are specially used on the sides of open frame racks. For more information on these three rack cable managers, read Vertical Rack Cable Management: Where to Start?

vertical rack cable manager types

Vertical Rack Cable Manager Types

Fiber Raceway System

Fiber raceway system is used to route and protect cables above racks. It consists of fiber raceway ducts, ladder racks, various interfaces, elbows and supports, etc. The fiber raceway duct often available in four sizes from 2″x 2″ to 4″ x 12″. The following video shows how to set up a good fiber raceway system for top of the rack cable management:

Copper/Fiber Patch Panel

Copper/fiber patch panel is used to manage cables in the rack. It is often a board or enclosure which allows you to connect cables in various combinations with a number of copper/fiber sockets. Copper/fiber patch panel helps to keep things organized and contained, therefore cables in the rack won’t hang out all over the place. For more information about copper/fiber patch panel, read How to Use Fiber Patch Panel for Better Cable Management and How to Select the Suitable Copper Patch Panel?


Horizontal/vertical rack cable managers, fiber raceways and copper/fiber patch panels are good ways to manage and route your rack cables to sure everything is easy to access and identify. It is suggested to select proper rack cable managers according to your needs during set-up and installation of network cabling system.

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Cat6 Patch Panel: Shielded vs Unshielded

Patch panel is a commonly used mounted hardware assembly that contains ports for connecting and managing incoming and outgoing fiber/copper cables. It is usually attached to network racks, either above or below network switches. According to the cable type, it can be divided into Ethernet patch panel and fiber patch panel. Ethernet patch panel is for copper cable management while fiber patch panel is for fiber cabling. There are also shielded and unshielded Ethernet patch panels for different kinds of twisted pair cables. This post will focus on Cat6 patch panel shielded vs unshielded.

Cat6 Shielded Patch Panel

Cat6 shielded patch panel often consists of a metal panel and Cat6 snap-in shielded keystone jacks, which is perfect for high RFI/EMI environments where interference is a risk. It is often used together with shielded Cat6 cable which has better signal transmission performance. Based on the number of ports it contains, shielded Cat6 patch panel can be classified into 48-port, 24-port and 12-port types. The following image shows a 24 port shielded Cat6 patch panel which features installer-friendly design for quick installation and organization of shielded copper cabling system.

24 Ports Shielded Cat6 Patch Panel

Cat6 Unshielded Patch Panel

Cat6 unshielded patch panel, on the other hand, is equipped with Cat6 snap-in unshielded keystone jacks. It is a more commonly used patch panel suited for most copper network systems. Like Cat6 shielded patch panel, unshielded Cat6 patch panel also has 48-port, 24-port and 12-port types. And the 24 port patch panel is the most popular one.

24 Ports Unshielded Cat6 Patch Panel

Cat6 Patch Panel: Shielded vs Unshielded

Cost—Cat6 shielded patch panel tends to cost more than the unshielded one. This is mainly due to more expensive Cat6 keystone jacks. And the use of Cat6 shielded cable will also add cost for the whole shielded cabling system.

Performance—Though the shielded Cat6 patch panel do cost more, it is better in helping to overcome alien crosstalk. In addition, it also provide such benefits as increasing immunity from outside electronic interference.

Can Unshielded Cat6 Cable Connect to the Cat6 Shielded Patch Panel?

In practical applications, there often arises some questions such as can I use unshielded Cat6 cables on Cat6 shielded patch panels? Can I use shielded Cat6 cables with cat6 unshielded patch panels? Or can I use Cat5e cables on Cat6 patch panels? Here will discuss these questions in details:

Generally speaking, if you are setting up a network with Cat 6 shielded cables, you should use shielded Cat6 patch panels, which ensures the entire line stays fully shielded and helps to prevent data loss. This rule shall be strictly followed where cables will be run very close to other cables or electronic devices. In environments where the amount of EMI or RFI is low, it is feasible to connect unshielded Cat6 cables to cat6 shielded patch panels or use shielded Cat6 cables with cat6 unshielded patch panels. As to connecting Cat5e cables to Cat6 Patch Panel, electrically it will make contact and work fine, though the Cat5e cable is “looser” terminated on a Cat6 jack. But you should only expect Cat5e performance on the cat6 patch panel.


Cat6 patch panel is the most popular cable management tool for Gigabit Ethernet copper network. And shielded Cat6 patch panels are ideal for high-speed networks such as data center. While unshielded Cat6 patch panels are for most home or small enterprise network applications. FS.COM supplies cost-effective Cat6 patch panels, shielded or unshielded, feed-through or punch down are all available.

Related Articles:

How to Select the Suitable Copper Patch Panel?

Should We Choose Punch Down or Feedthrough Patch Panel?

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EVPN vs VPLS: What’s the Difference?

EVPN and VPLS are two technologies that provide Ethernet multipoint services over IP/MPLS networks. And as everyone knows, VPLS has been available and widely deployed for many years. EVPN, however, is a new upcoming technology which is considered to be a more efficient and feasible alternative to VPLS. Even so, someone still configure VPLS on their networks and use it to good effect. Then what’s exactly the difference between EVPN and VPLS? Which one is better? This post will focus on EVPN and VPLS tutorials, and discuss EVPN vs VPLS differences.


VPLS, be short for virtual private LAN service, is a telecom carrier-provided service. It enables customer to create a logical LAN structure between geographically separate sites. Actually, VPLS creates a virtualized data switch at the service provider, which links multiple remote sites together as if they were connected to a same physical switch. This helps a lot in simplifying network deployment and management, especially for data center interconnection.



Like VPLS, EVPN also provides virtual multipoint bridged connectivity between different Layer 2 domains over IP/MPLS backbone network. it is typically composed of customer edge (CE) devices (host, router, or Gigabit Ethernet switch) and provider edge (PE) routers. The PE routers often include an MPLS edge switch (MES) such as a 10GbE switch, which acts at the edge of the MPLS infrastructure. The following is a typical EVPN deployment. Traffic from data center 1 is transported over the service provider’s network through MES1 to MES2 and then onto data center 2. DCS1, DCS2, DCS3, and DCS4 are the data center switches.

EVPN vs VPLS -evpn

EVPN vs VPLS: What’s the Difference?

As mentioned above, EVPN is a more recent technology which aims to overcome the challenges VPLS meets. So it is more advanced in the following aspects:

EVPN vs VPLS – Signaling Protocols

VPLS features two kinds of signaling protocols: LDP and BGP. EVPN, however, adopts BGP as the only one service signaling protocol.

EVPN vs VPLS – CE Multihoming

VPLS only implements single-active solutions. EVPN implements two CE multihoming solutions: single-active (one active, N standby) and all-active (with known uni-cast per-flow load balancing).

EVPN vs VPLS – MAC Learning

VPLS only supports data-plane MAC learning on its local Attachment Circuit (AC), which can easily lead to stale forwarding state. EVPN also performs data-plane MAC learning on its local AC, but it relies on control-plane MAC learning between PEs. This will reduce unknown uni-cast flooding and implement a flush mechanism in BGP.

Will EVPN Replace MPLS?

Though EVPN has much advantages than MPLS, it doesn’t mean it’s the best solution for everything. For example, VPLS is much less consuming in terms of control plane and it uses up more service MPLS labels than EVPN. In these circumstances, EVPN will not replace MPLS. EVPN vs VPLS, which will you choose for your network?

Related Articles:
VPN vs MPLS: What’s the Difference?

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AC Switch vs DC Switch: What’s the Difference?

The first step on integrating a switch into the network is to get it powered up. And as to power supply, there are AC and DC power for network switch, both of which are used for increasing network uptime. Then what’s the difference between AC power Switch and DC power switch? Which type shall we used for our network? This post will give a detailed introduction for the difference between AC Switch and DC switch, and set out how to make a proper decision over AC Switch vs DC Switch.

AC Switch vs DC Switch: What Are They?

AC powered Ethernet switch often has a fixed AC power supply connector, thus it generally gets powered up through power cables such as IEC power cord, NEMA power cord, etc. PoE switches are typical AC switches. Take FS 24 port PoE switch as example, which is equipped with a single 100-240V AC power supply connector (as shown below). It is easy to power up AC switch. All you need to do is connect it to the power socket with proper power cable. For some advanced network switch, turning on its power switch is also necessary.

AC switch vs DC switch

DC powered Ethernet switch can be configured with an internal or external DC power supply. And the external DC power supply is more popular nowadays, which is also known as redundant power supply. Modern fiber switch often has more than one redundant power supply (e.g the following FS 10GbE switch is equipped with two DC power supply). Except for powering up switch, the DC redundant power supply can also protect other power supply when it fails with shorted outputs.

AC switch vs DC switch

AC Switch vs DC Switch: What’s the Difference?

In the market, there are Ethernet switches that support only AC power supply or DC power supply, and there are also some switches which can be used with both AC and DC power supplies. However, the switch can only support one type of power supply at the same time. That’s to say, if you use DC power supply to power up your switch initially, the switch will detect it and operate with DC power. In this case, AC power supply installed in the switch will be disabled. Even if you try to install AC power supply when the switch is operating with DC power, it will also disable the AC power and generates an alarm. So remember not to mix AC and DC power supplies in a switch.


AC and DC power supplied Ethernet switches are all commonly used nowadays. You can select one or the other according to your own case and needs. FS provides both AC and DC switches. For example, we have AC switches such as 8/24/48 port PoE+ Managed Switches which support up to 600W. High quality DC switches are also available. Customers can also custom the power type of switches.

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