Author Archives: Amelia.Liu

What’s the Differece: 10GBASE-SR vs 1000BASE-SX

As the development of fiber optic network, there appears lots of industry standards for fiber optic transceivers. Although transceivers with different standards may have different features and performance, they sometimes can be used in the same switch port. Thus, many people may get confused by these transceivers. For example, 10GBASE-SR and 1000BASE-SX transceivers can both be inserted into the Cisco Catalyst 2960S-48TD-L switch, but the 10GBASE-SR transceiver may not work fine with the 1000BASE-SX module in another switch. Why? This post will discuss 10GBASE-SR vs 1000BASE-SX and whether 10GBASE-SR transceiver can down-support connect to 1000BASE-SX transceiver.

connect 10GBASE-SR to 1000BASE-SX

10GBASE-SR vs 1000BASE-SX

As mentioned above, 10GBASE-SR and 1000BASE-SX are two kinds of industry standards for fiber optic transceivers. This part will introduce them in turns.

10GBASE-SR

10GBASE-SR is defined in the IEEE 802.3 Clause 49 standard, specially designed for multi-mode fiber optic medium that uses 850 nm lasers. It has a data transmission rate of up to 10.3125 Gbps and can be used over multiple cabling options. But the transmission distance may differ as the fiber cable changes. For example, when used over OM1 cabling, the 10GBASE-SR has a maximum working distance of 33 meters, as opposed to 82 meters when applied over OM2 cabling. Nowadays, the 10GBASE-SR module usually applied over OM3 and OM4 cablings to give a more structured optical cabling used in large buildings. And the transmission distance respectively are 300m and 400m.

1000BASE-SX

Like 10GBASE-SR, 1000BASE-SX is also an IEEE 802.3z standard for the multi-mode fiber optic cabling. But it has a minimum transmission distance of 220m and a maximum of 550m. Offering 1Gbps data transmission rate, 1000BASE-SX modules are mainly used to connect high-speed hubs, Ethernet switches, and routers together in different wiring closets or buildings using long cabling runs.

Can 10GBASE-SR Transceiver Down-Support Connect to 1000BASE-SX Transceiver?

10GBASE-SR modules are generally referring to 10GBASE-SR SFP+ transceivers, and 1000BASE-SX modules are usually 1000BASE-SX SFP transceivers. And since SFP+ and SFP transceivers share the same size (as shown below), SFP transceivers can often used in most SFP+ ports (For example, almost all SFP+ ports of Cisco switch can accept SFP transceivers). Then can a 10GBASE-SR SFP+ transceiver down-support connect to the 1000BASE-SX SFP transceiver?

10GBASE-SR vs 1000BASE-SX

10GBASE-SR vs 1000BASE-SX Transceivers

The answer is no. Unlike copper SFP transceivers, 10GBASE-SR SFP+ transceivers do not have such functions as auto-negotiation. In fact, both 10GBASE-SR SFP+ and 1000BASE-SX SFP transceivers can only run at the rated speed fixed by the electro-optical conversion ASIC built into the transceiver hardware. That’s to say, 10GBASE-SR SFP+ transceivers can only run at 10Gbps and 1000BASE-SX SFP transceivers run at 1Gbps. So there is no such fiber link that one end does 1G while the other end does 10G.

10GBASE-SR vs 1000BASE-SX: Have You Known the Differences?

To conclude, although 10GBASE-SR and 1000BASE-SX share something in common, they are totally different Ethernet standards for transceivers. 10GBASE-SR SFP+ transceivers mainly work in 10G links, while 1000BASE-SX transceivers can only run at 1Gbps even though in the SFP+ slot. Thus, it will not work out to connect a 10GBASE-SR SFP+ transceiver with a 1000BASE-SX SFP transceiver.

NAS vs SAN: What’s the Difference?

In the era of information technology, data has become the most critical asset for companies. Without access to their data, companies may not be able to provide their customers with desired services. Thus how to effectively store, access, protect and manage critical data is a new challenge facing IT departments. Direct attached storage (DAS), network attached storage (NAS) and storage area network (SAN) are three main technologies for storage networking. Among them, NAS and SAN are similar in using internet technology to ensure users can access and manage their storage data easily. But they are in fact two different storage technologies. This post will focus on NAS vs SAN.

What Are Network Attached Storage and Storage Area Network?

Network attached storage is a file level storage system served as a local area network (LAN) node. It is usually referred to as a single storage device connected to network, allowing clients or associated devices in the LAN to share file-based data through a standard Ethernet connection.

Network attached storage

Unlike network attached storage, storage area network provides block-level network access to storage. It often consists of hosts, switches, storage elements, and storage devices that are interconnected using a variety of technologies, topologies, and protocols.

storage area network

NAS vs SAN: What’s the Difference?

As the name implies, a network attached storage consists just of storage device while a storage area network is a network. The followings are some other differences between them:

NAS vs SAN

1. NAS vs SAN Connections

The network attached storage system can be connected directly to the network using an Ethernet cable into an Ethernet switch. Almost any device that can connect to the LAN (or is interconnected to the LAN through a WAN) can connect to a network attached storage and share files with the use of NFS, CIFS or HTTP protocol.

In contrast, devices in storage area network system are connected together using a network fabric, such as iSCSI or Fibre Channel. And only server class devices with SCSI Fibre Channel in a virtual computing environment can be connected to the storage area network.

2. NAS vs SAN Data Identify

As mentioned above, network attached storage is a file level storage system. So it identifies data by file name and byte offsets, transfers file data or file meta-data and handles security, user authentication, file locking.

Storage area network stores data in a block level. It addresses data by disk block number and transfers raw disk blocks. In this case, storage area network has lower latency and higher performance than network attached storage.

3. NAS vs SAN Backups and Mirrors

Backups and mirrors of network attached storage are done on files, not blocks, to save bandwidth and time. And the snapshot can be tiny compared to its source volume.

Backups and mirrors of storage area network require a block by block copy, even if blocks are empty. A mirror machine must be equal to or greater in capacity compared to the source volume.

NAS vs SAN: Which One to Choose?

Network attached storage and storage area network are two popular solutions for networking storage. Which on to choose is largely depend on your actual requirements. With much simpler design, network attached storage is far less expensive than storage area network. And it is ideal for those who looking for an easily implemented storage solution. While storage area network is a high-performing and complex system, suitable for companies looking for top-of-the-line storage performance and reliability.

Hyperconverged Infrastructure Basics

Hyperconverged infrastructure has been talked a lot in recent years and its adoption is skyrocketing in data centers. However, many people are still confused by this term. This post will introduce it in details.

What’s Hyperconverged Infrastructure

Hyperconverged infrastructure is often named HCI. It is introduced in 2012 to describe a fully software-defined IT infrastructure that virtualizes all the elements of conventional hardware-defined systems. In other words, the networking and storage tasks in the hyperconverged infrastructure are implemented virtually through software rather than physically in hardware. Generally, hyperconverged infrastructure is at least composed of virtualized computing (a Hypervisor), a virtualized SAN (software-defined storage) and virtualized networking (Software-defined networking). It can be utilized as a way to pool together resources so as to maximize the interoperability of on-premises infrastructure.

Hyperconverged Infrastructure

Hyperconverged Infrastructure VS Converged Infrastructure

Hyperconverged infrastructure and converged infrastructure are two alternative solutions to replace the traditional IT infrastructure. This part will tell the differences between them to help you choose one over another for your network deployment.

Hyperconverged Infrastructure VS Converged Infrastructure

Hyperconverged VS Converged Infrastructure Components

Converged infrastructure defines compute, storage, networking and server virtualization—which are the four core components in a data center—as one dense building block. Hyperconverged infrastructure is born from converged infrastructure and the idea of the software-defined data center (SDDC). Besides the data center’s four core components, hyperconverged infrastructure integrates more components such as backup software, snapshot capabilities, data deduplication, inline compression, WAN optimization and so on.

Hyperconverged VS Converged Infrastructure Principle

Hyperconverged infrastructure is a software defined approach. It means the infrastructure operations are logically separated from the physical hardware, and all components in a hyperconverged infrastructure have to stay together to function correctly. While converged infrastructure is a hardware-focused, building-block approach. Each component in a converged infrastructure is discrete and can be used for its intended purpose. For example, the server can be separated and used as a server, just as the storage can be separated and used as functional storage.

Hyperconverged VS Converged Infrastructure Principle

Hyperconverged VS Converged Infrastructure Cost

Converged infrastructure allows IT to use a single vendor for end-to-end support for all core components instead of the traditional approach where IT might buy storage from one vendor, network from another and compute from another. It also offers a smaller footprint and less cabling, which can reduce the cost of installation and maintenance.

Hyperconverged infrastructure allows IT to build, scale and protect your IT infrastructure more affordably and effectively. For example, a 10GbE Access Layer Switch (8*10/100/1000Base-T+8*1GE SFP Combo+12*10GE SFP+) specially for hyperconverged infrastructure only costs US$ 1,699. And the software-defined intelligence reduces operational management, providing automated provisioning of compute and storage capacity for dynamic workloads.

Conclusion

It is reported that hyperconverged infrastructure will represent over 35 percent of total integrated system market revenue by 2019. This makes it one of the fastest-growing and most valuable technology segments in the industry today. The upfront costs of hyperconverged infrastructure may be a little high now, but in the long term it can pay off.

Can A Computer Connected to the PoE Switch?

The PoE switch is commonly used in various networks. It can be low-cost unmanaged edge switches with a few ports or complex multi-port rack-mounted units with sophisticated management. When used in small or home networks, many people may wonder if it can be connected directly with a computer. This post will discuss this question in details.

What Are PoE and PoE Switch

Before the discussion, it is necessary to have a basic understand of what are PoE and PoE Switch:

PoE

As demands for connection from networking devices such as IP phones, IP cameras and access points increase, deployment complexity and cost rise as well. For less cable usage and investment, Power over Ethernet (PoE) technology is developed to provide both data connection and electrical power to devices through just one Cat5/Cat5e/Cat6 cable.

PoE Switch

PoE switch is a network switch that has Power over Ethernet injection built-in, which can transmit both power and data through an Cat5/Cat5e/Cat6 Ethernet cable at the same time. This kind of switch makes it easy for different sectors to deploy powered devices like VoIP phones, wireless access points and IP surveillance cameras in challenging places like ceilings, walls, outdoors, or wherever electrical outlets are not easily available.

poe switch connection

Can A Computer Connected Directly to the PoE Switch?

As shown below,PoE switch usually have the same RJ45 port as a computer. So many people will think they can be connected directly. But do not forget that PoE switch may also transmit electrical power through the RJ45 port and Cat5/Cat5e/Cat6 cable to the computer. Then can a computer be connected directly to the PoE switch? This is largely depend on the switch you have:

poe switch

If you have a PoE switch that conforms to 802.3af (the PoE standard) or 802.3at (the PoE Plus standard) and doesn’t claim to be “passive”, you can definitely connect your computer with it. This is because this kind of PoE switch has the function of PoE detection which is designed to avoid damage to non-PoE devices. In other words, when you connect other network devices to your PoE switch, it will communicate with the these devices whether they need power or not. Power is only injected if and when this negotiation is successful. Ethernet devices such as phones and access points are detected by the switch as accepting PoE and will receive the additional power feature from the PoE switch/port. Whereas a computer and other non-PoE devices will not be detected as having PoE capability and will just use the data communications features of the port.

computer connect to poe switch

However, there exists a class of PoE switches, usually referred to as “passive” or “always on”, which supply power without PoE detection. Why would anyone do this? Because this kind of PoE switch is significantly cheaper. Whether it damages your device depends on the voltage of the passive PoE switch and your devices. For a computer, it may be damaged for excessive voltage or current.

Conclusion

PoE switch is a dedicated device that contains multiple Ethernet ports to provide power and network communications. It is usually used in NVR/IP camera networks. For small or home networks, if you want to connect a computer to the PoE switch, make sure your switch follows the standard 802.3af or 802.3at PoE requirements. So can you connect a computer directly to your PoE switch?