Category Archives: Network Switch

Why Choose 10 Gigabit ISCSI Switch for SAN?

With the development of technology, many users are considering upgrading to 10 Gigabit Ethernet switch. Of course, when it comes to the edges of the fiber switch, the obvious advantage of the Gigabit switch is the speed. The Gigabit Ethernet and 10GbE switch can also bring other advantages, such as reducing cabling and bottlenecks. In addition, another important advantage is iSCSI support. This involves our theme today: 10G iSCSI switch for SAN, which is highly scalable because its capacity can be added as required.

Ethernet Switches

What is the SAN (Storage Area Network)?

The SAN is a dedicated high-speed network or subnet that connects shared pools of multiple storage devices to multiple servers. The SAN is usually assembled through three main components: cabling, host bus adapters (HBAs), and switches connected to storage arrays and servers. Now, let’s focus on the SAN switch. What need SAN switches to do is to move storage traffic. SAN switches are usually FC switches, which are compatible with many FC protocols based on SAN. At the same time, SAN switches can also be based on Ethernet. Such switches should only process traffic on IP SAN to maintain predictable performance. Ethernet switches provide traffic for IP addresses. They treat iSCSI storage targets as IP addresses. These Ethernet switches are what we call iSCSI switches.

Those people who focus on 10G devices have a common misconception that only an expensive and difficult-to-maintain fiber connect network is needed to effectively connect distributed storage SAN. While the FC has its advantages, the iSCSI switch can run economically on your existing Ethernet hardware (although the dedicated hardware is better) and works well on a 10G network.

Understanding the ISCSI Switch

When we need to build our SANs or iSCSI network, we usually heard of DELL iSCSI switch, HP iSCSI switch and so on. However, what is the iSCSI switch? The iSCSI switch is a device that processes and channels data between the iSCSI initiator and the target on a storage device. ISCSI traffic is usually high speed and high capacity, and it needs to be provided with minimal delay. Unlike dedicated FC SAN switches, iSCSI switches are standard Ethernet network switches and can be used for iSCSI traffic optimization. ISCSI switches provide reliability while enhancing network control and supporting quality of service.

10G ISCSI Switch

Figure: 10G ISCSI Switch

The Reason Why Choose 10G ISCSI Switches for SAN

Then, why we choose 10G iSCSI switches for SAN? There are three main reasons, they can be concluded as follows:

  • Flow control: building the SAN by using 10G iSCSI switches can help the host avoid being overwhelmed by the high traffic associated with iSCSI storage through allowing the host to control the rate at which data is received, and use flow control. Traffic control can also help prevent packet loss and avoid increased delays in iSCSI storage networks.
  • Jumbo frame: the high payload of jumbo frames can be processed by providing fewer frames to the switch, thereby improving the efficiency of data transmission. This can improve 10G iSCSI performance, but using jumbo frames may cost more. Basically, the better the iSCSI switch is, the better your SAN will be.
  • Link aggregation: also known as port trunking, this feature combines switch ports into higher bandwidth trunks to increase throughput and create redundancy. This is significant for you to build your SAN.

Conclusion

The world’s needs for data is growing, and nothing seems to be able to solve this problem. The video is becoming more and more high-definition, VR application is more and more used, and even the daily web pages are upgraded. If your business is already feeling the pressure of a data bottleneck, upgrading to a 10G iSCSI switch will put you back on the fast lane.

Layer 3 Switch VS Router

When it comes to layer 3 switch and routers, many networking beginners may be confused about the two terms, because they all use IP packets, check the destination address and pass packets according to the routing rules. In terms of these aspects, they are the same. But in fact, they are different in many ways. Layer 3 switch vs router, what’s the difference?

layer 3 switch

Figure 1: layer 3 switch

What Is Layer 3 Switch?

While, layer 3 switch is a product of technology to improve on routers that used in large local area networks (LANs), such as corporate intranets. The most important purpose of the layer 3 switch is to speed up the data exchange within the large LAN. And its routing function is also for this purpose. It can be routed once and forwarded many times.

What Is Router?

Performing the traffic directing on the internet, the router is a networking device, which forwards data packets between computer networks. Data (like emails or web pages) sent through the internet, is in the form of data packets.

router

Figure 2: router

Layer 3 Switch VS Router: What’s the Difference

The hardware technology used to build the unit of layer 3 switches and routers is different. Merging that of traditional switches and routers, the hardware inside a layer 3 switch replaces some of a router’s software logic with hardware to promote performance in some situations. But layer 3 switch vs router, what are the differences between a router and a Layer 3 switch?

  • Flexibility-Mixing and matching layer 2 and layer 3 switching by layer 3 switches are allowed, which means that a layer 3 switch can be configured as a layer 2 switch to operate.
  • Density of port-Compared to routers, the port count of the layer 3 switches is higher, while the port density router is lower than that of the layer 3 switches.
  • Hardware/Software decision making-The hardware technology which is used to making forwarding decision is the key difference between layer 3 switches and routers. The hardware technology used in layer 3 switches is ASIC to forward decision while the hardware technology used in routers is the software logic.
  • Cost-Compared to routers, the layer 3 switches have higher cost performance. Generally, high-performance routers are usually much more expensive than the layer 3 switches.

Layer 3 Switch VS Router: When to Use Each

Now let’s look into the scenario where to use layer 3 switches and router.

L3-Switch
  • If you need more throughput and direct access, a layer 3 switch is the best choice.
  • If your Hub rooms need to be connected, and a L3 decision need to be made, besides, direct server form connectivity requires more Ethernet interfaces, then you can use a switch.
Router
  • If you want to connect a ISP directly for providing internet, to deploy a router is best.
  • If tunnels between your different offices (securely connecting 2 offices over public internet) need to be built, then you need a router .

Conclusion

After explaining the layer 3 switches and routers above, I think you’ve had some knowledge of layer 3 switch vs router. To put it simply, they have the same functions, but each has their own advantages and disadvantages. In general, the layer 3 switch is mainly used in LAN environment, and routers are used in WAN environment. If you are looking for them, consider FS.COM. Besides, if you have any questions about the deployment of the network, please contact us at any time for help.