Go FCoE completely subvert storage network architecture pattern Date: 2010-3-22

The presence of FCoE in the storage field has caused a stir. In order to make it healthy and fast forward, the FCOE standard was introduced in June 09, which indicates that this technology will be more mature to the data Center storage transport protocol to lead the goal of the advance. Like many of the new technologies of the past, there are some positive fcoe, some people watching and others dismissive. However, most people are still looking forward to FCoE, but it is still a while before it wants to become mainstream.

In June 2009, the T11 Technical Committee finally submitted the FCoE (Fibre Channel over Ethernet) standard as an ANSI standard to the INCITS (International Information Technology Standards Committee) for review and is expected to be approved in the near future. Although FCoE is the final standard is still the last step, but has been basically no suspense.

The emergence of FCoE has been favored by the industry, is considered to be a complete subversion of the current pattern of storage network architecture, as the future-leading storage transport protocol. Enhanced Ethernet (converged enhanced Ethernet,cee) is the most important related part of the FCOE protocol, which is the protocol that transmits FC encapsulation over Ethernet. CEE is an Ethernet with FC characteristics, which can transmit FCoE storage data, data Center application system and cluster. CEE is a lossless Ethernet (lossless Ethernet) that can transmit FCoE data without compromising. Currently, CEE uses three priority groups, including IPC, LAN, and WAN.

Organic combination of Ethernet and Fibre Channel

The advent of FCoE stems from the idea that the current large-scale application of Ethernet and Fibre Channel should be combined. The combination of the two will give the data center the benefits of reducing the number of devices, making full use of Fibre Channel, and storage centralization. The benefits of FCoE to large enterprise data centers are obvious because large enterprises invest billions of of dollars a year in Fibre Channel storage, so it is tempting to make the most of Fibre Channel in 10Gbps of enhanced Ethernet. It should be said that the combination of Ethernet and Fibre Channel is great and exciting.

FCoE can also help with the application of fibre sans in high-speed short-distance networks, such as the blade server Backplane and virtualized servers that are common in the perimeter of the data center.

The concept of FCoE is simple: The Fibre Channel architecture runs on the 10Gbps Enhanced Ethernet (CEE) to form a converged network, featuring FC data frames that remain unchanged and use the same name; Ethernet requires larger data frames (Jumbo Frames) than 1500 bytes; Ethernet must become a storage data that is not lost and is guaranteed to transmit intact. FCoE is an encapsulation protocol that is less than iSCSI headers but more than FC, and the encapsulation protocol does not replace storage interfaces, such as FC or SCSI. FCoE reduces the number of server and switch ports, reduces cable and power consumption, and increases link usage efficiency. At the same time, because of the use of 10Gbps CEE, its transmission speed is high.

FCoE does not apply to all situations, and typically a small, Ethernet-only storage environment does not require a FCOE of the connectivity performance associated with it. But for users using Fibre Channel, FCOE enables Fibre Channel storage to penetrate every corner of the data center.

Two related protocols are required to achieve this level of application: First, the FCoE itself, a transport standard that makes the local Fibre Channel architecture run on Ethernet; The second is enhanced Ethernet (CEE), which requires FCOE to transmit Fibre Channel over Ethernet.

The FCOE standard enables Fibre Channel to run through the data Link layer bridge between multiple enhanced Ethernet LAN segments to support SAN management domains by maintaining multiple logical Fibre Channel sans spanning 10Gbps-enhanced Ethernet segments. The FCOE standard does not cause any performance loss to Fibre Channel and does not alter its architecture.

Enhanced Ethernet, also known as Fusion Enhanced Ethernet (CEE), Datacenter Ethernet (Data center Ethernet), or Datacenter Bridge (data center BRIDGING,DCB), replaces the TCP/IP network layer protocol with local Data link layer Ethernet. Traditional Ethernet networks often have network congestion, latency and drop frames, which are not suitable for fibre Channel transmission, but 10Gbps enhanced Ethernet achieves the "lossless (lossless)" Network by abandoning TCP/IP.

The "lossless" network environment is a prerequisite for priority traffic control (Priority), scheduling (ETS), and FCoE protocol applications (also a prerequisite for blocking management, although tempting but not necessary for FCoE). These are the necessary conditions for the Fibre Channel architecture to run directly on the 10Gbps Ethernet segment without losing any performance.

FCoE and Data center

The current converged network adapter (converged network ADAPTERS,CNA) is still in the internal testing state of the enterprise. Customer's biggest hope for FCoE is to ease the data center's increasingly strained computing environment and connect it to the SAN. FCoE will likely extend and balance existing Fibre Channel resources in the Data Center computing environment.

Together with CEE, FCoE can provide data center administrators with the following convenience:

Use existing centralized storage instead of direct-attached storage (DAS);

Balance Fibre Channel resources so that administrators no longer need to purchase separate iSCSI sans;

Provides a 10Gbps speed CEE for high-performance environments.

Some of the problems facing some high-performance environments are just FCOE and CEE can be solved. These issues include the need to deploy iSCSI sans in centralized storage to eliminate direct-attached storage, as well as the energy costs associated with a large number of complex cables and redundant devices.

This is also the goal of most FCOE-related research, and in 2009, FCoE is still used for the above peripheral environment. As FCoE is proving increasingly stable and formalized, we believe FCoE will appear in key applications in the data center over the next few years. FCoE will become mainstream in a year or two after a few companies take the lead in using them. A FCOE deployment test has emerged in 2009, and the 2010 commercial FCoE is expected to appear in the peripheral applications of the data center.

While there are many organizational and budgetary challenges, we still believe that centralized storage on existing Fibre Channel Sans will return more than it pays.

1. Use centralized storage in an intensive server environment

In the past, blades and virtual servers at the periphery of the data center generally used DAS methods to store data; Centralized Ethernet architectures based on CEE and FCoE provide greater bandwidth, higher speeds, and the ability to connect to Fibre Channel Sans. Extending existing fibre storage to these I/O-intensive high-performance environments eliminates inefficient das storage and balances existing fibre storage sans without the need to purchase iSCSI Sans. CEE can also improve the I/O intensive environment because it provides greater bandwidth and speed.

2. Reduce equipment complexity and rebuild data center by consolidating servers

Another early application of FCoE is to help servers and network consolidation. Typical server clusters in a data center typically have 5~7 I/O interfaces for other networks and redundant devices. FCoE and CEE can unify ports through multi-protocol switching and host-based can, which greatly reduces the number of network devices, the interfaces of servers to the network, and cables connecting different clusters. For example, the number of interfaces may be reduced to two 10GbE ports, two cables, and two switching interfaces.

Another benefit of consolidation is the ability to support FCoE's CNA to provide a standardized approach to fibre SAN connectivity, which simplifies the physical architecture and its support. For I/O connectivity, the integration will no longer require the installation of Fibre Channel services since all data center servers have CNA, so IT departments or other policy departments can use Fibre Channel services anytime, anywhere.

3. Helping to improve energy efficiency in data centres

In the data center, consolidation and network unification also reduce the energy consumption associated with network and storage. In general, the network does not consume more energy than storage. The centralized structure reduces the number of cables, the number of interfaces, and the number of redundant servers to achieve energy savings. However, by using FCOE to expand Fibre Channel storage for more data center servers, the energy consumption of additional disk arrays is reduced, and this part of the energy consumption is considerable. Replacing multiple Das Storage and iSCSI arrays with San centralized storage can significantly reduce the array's need for energy, space, and cooling.

4. Consistent SAN Connectivity

CNA enables dynamic Fibre Channel Sans to be deployed in Ethernet services. This eliminates the need to configure additional Fibre Channel ports on the server to establish a connection. Fibre Channel connectivity can also replace inefficient Das methods, simplify the physical architecture and support, reduce the number of complex devices that are attached to each other's structures, and enable storage administrators to achieve efficient storage resource management, which means Fibre Channel replaces Fibre Channel +ISCSI and/or DAS.

Although FCoE and CEE have not officially become standard, but already have a large number of vendors support and recognition. But standards are also very important, which is the key to deep integration and synergy. Setting standards will enable administrators to trust FCoE and CEE on virtualization and blade servers on the periphery of the data center, and to be able to trust their capabilities in the datacenter core environment. Although the standard has not yet been formally established, but has attracted enough manufacturers and enterprises to bring commercial products to the adopters, is expected 2010 FCoE and CEE will become mainstream products. In addition, most of the storage and Ethernet vendors are involved in the development and integration of FCOE equipment suppliers in the market, including Brocade, Cisco, Emulex and QLogic.

At the same time, InfiniBand vendors have seen extended opportunities based on high-performance Computing (HPC). While only a handful of vendors are involved, modifying InfiniBand will be more easily approved, and InfiniBand has provided many of the CEE that will be provided in the future.

when to deploy FCoE

To know when FCoE can be widely used, the key is to understand how data center managers make decisions. "Change" means the budget for the investment and installation of the equipment, management and other operations required. Device upgrades are usually based on two things: the first is that the service level is not up to the requirements, and the second is that the operating costs of the old equipment are higher than the new ones. Thus, in general, the introduction of new technologies can only occur if the opportunity and management costs of the old technologies are higher than the cost of transforming them into new technologies.

As a result, almost all new technologies have undergone a relatively long process from being presented to adoption. Pragmatism and the impact of the budget outweigh the experts ' optimism about the project. As a reference, you can flip through past experts ' predictions of certain technologies. InfiniBand, iSCSI, and even 10Gbps Ethernet have reached a certain number of market penetration rates over a longer period of time than initially expected. Some technologies never reach a penetration rate of 50%; iSCSI and InfiniBand maintain less than 50% of the market penetration rate has been more than 6 years, 10GbE has experienced 7 years under 50% market penetration rate.

The adoption rate of technology varies according to the size and industry characteristics of the enterprise. For businesses that spend more than 1 million dollars a year on storage, the adoption rate of new technology is much higher, because it brings performance improvements. And for organizations that spend less than 100,000 dollars a year on storage, the need for ease of use is the main reason they are more iSCSI and Nas. For small and medium-sized enterprises, the adoption rate of Fibre channel is less than 50%.

There are also examples of rapid increases in technology adoption rates, but even fast-moving cases, such as Fibre Channel, have been going on for several years to become mainstream connectivity technologies. The rapid growth of Fibre channel is mainly due to the drawbacks of existing storage network technologies that outweigh the deployment problems and costs associated with the use of new technologies. However, in such an ideal environment, fiber channel has been used for 4 years to become the mainstream technology.

FCoE mainly relies on two foundations. One is the new standard for placing the Fibre Channel architecture in the Ethernet architecture, which was formally released by the T11 Technical Committee in June 2009. The other is a new standard that can provide FCOE specified reliable Ethernet transmission. This part is still in progress and is moving quickly towards formal standards.

CEE, the early term "Data center Ethernet" (Data-center ethernet,dce), which FCoE requires, is Cisco's proprietary terminology. The new 10Gbps CEE no longer requires TCP to deliver packets, but rather to use the Ethernet Data Link layer, which is more like a Fibre Channel data link layer secure transmission.

For some people, using CEE means transferring the storage protocol to the LAN, but this time it's not the same. The new CEE network has all the storage network features, including virtual channels, priority and quality services, secure transport, and transparent fault-tolerant redundant connections.

Another possible reason for CEE is that traditional Ethernet use of TCP/IP can pose a security problem. Unlike CEE, Ethernet is always in the non-routed data transfer layer. With CNA and CEE, connected Sans and LANs share the same physical pipeline, but are still logically separate and the quality of service is still protected.

Although there are still many differences between iSCSI and FCoE using the same transmission, iSCSI is valuable for its low cost and ease of use, but it does not provide the same performance as Fibre Channel. There are many reasons for this, too far from TCP is one of the reasons.

Data center managers now have the question of whether future FCoE will become important. This question is very simple, of course, the answer is yes. But the hard question is: "When will the FCoE replace the standard Fibre Channel?" "or" FCOE will replace Fibre Channel and iSCSI storage. "The answers to these questions need to be determined by several factors, including the size of the enterprise and the number of IT budgets." As shown in Figure 2, Fibre Channel storage is gradually replaced by FCoE and iSCSI.

In the early stages of promotion, the FCoE will apply to large organizations, which need 10Gbps of speed to sustain infrastructure investment and have IT specialists to solve deployment problems. iSCSI storage is primarily used for small organizations and special areas that do not require maximum storage performance. Over time, the FCoE costs will fall, the deployment challenges will be resolved, and the mainstream market can begin to enter. With the help of CEE and 10Gbps, iSCSI will overcome the lack of performance to find the right market in large enterprises.

Ultimately, the deployment of CEE will make FCoE possible, while iSCSI and NAS storage performance will also improve. As a result, in the near future, CEE will become the mainstream of all LAN and SAN protocols.

The emergence of FCoE has put forward a new demand for enterprise equipment performance, that is, the network speed requires 10Gbps. As a result, enterprises that are upgrading Fibre Channel to 8Gbps are likely not to deploy FCoE in the near future. However, businesses that still use 4Gbps or even 2Gbps devices should soon be upgraded to 10Gbps.

Remember that when FCoE first released, there was a lot of skepticism, because it was the only way the IT environment needed a new transmission and protocol. Now there are two more sophisticated networks, Fibre Channel SAN storage and Ethernet LAN storage. In addition, although InfiniBand has recently gained widespread attention, it does not look like a universal way of transmitting data for LAN and SAN instead of Ethernet.

FCoE Market

Although the process of stepping into the FCoE will not be as easy as from 100Mbps Ethernet to 1Gbps Ethernet and from 4Gbps Fibre Channel to 8Gbps Fibre Channel, vendors continue to develop CEE and FCOE products. Because the integration of San and LAN into the public architecture also requires upgrading of existing Ethernet hardware, which requires new low latency Ethernet devices.

Increasing the virtual I/O layer will also drive CNA to replace the HBA. Virtualization has been a key catalyst for dynamic It, information lifecycle management, cloud computing, and many other achievements. However, the existing LAN and SAN protocols do not support port virtualization. Therefore, increasing virtual I/O will enable CEE data transfer to play a greater role in support, and will also help virtual I/O detach from the converged host adapter.

Many vendors have started or are planning to launch CEE and FCoE products (although there are no local FCOE storage requirements). Manufacturers like JDS Uniphase have introduced FCoE testing equipment (JDS Uniphase recently acquired Finisar's Network Tools Division).

FCoE market prosperity may also be one of the reasons for its success. Traditional Fibre Channel vendors have also started releasing FCoE products, while Ethernet vendors and even InfiniBand vendors are starting to offer CEE devices. For example, InfiniBand vendors Voltaire and Mellanox have released 10Gbps of CEE equipment, competing with Cisco and Brocade. The current market price for CEE devices is about $1000 per port and almost twice times the standard 10Gbps Ethernet port.

who is the beneficiary of FCoE.

The beneficiaries of FCOE include large enterprises and small and medium-sized enterprises. Large IT organizations will be able to integrate server I/O transfer into flexible, virtual data transfer modes to conserve space, energy, and cabling. In addition, large enterprises will have higher connection speeds due to increased bandwidth. This is because FCoE is backward compatible with existing Fibre Channel networks and is compatible with new high-speed networks for other storage protocol data.

For small and medium-sized enterprises, the reason for the benefit in FCoE is that these enterprises will hardly need to choose the transmission mode in the future. Because no matter what, the result is using Ethernet. This means that small and medium enterprises can now deploy NAS and iSCSI storage on standard Ethernet. In the future, if there is a need for Fibre Channel storage, you can still leverage FCoE to maximize the functionality of NAS and iSCSI storage. This only requires a simple upgrade of existing Ethernet.

The reason many storage vendors support FCoE is that FCoE has pioneered a path for converged data transmission and has been able to take full advantage of the enterprise's past investment in I/O technology. What manufacturers need is to transfer physical and data link layers from Fibre Channel to Ethernet with minimal investment. When using FCoE initially, the price of the CNA and CEE that support FCoE must not be cheaper than the 8Gbps light channel. But as the number of uses and the number of manufacturers increase, market competition will promote the decline in prices.

It can be said that almost everyone is the beneficiary of FCoE. IT organizations using Fibre Channel can continue to make full use of old equipment; Organizations that have not yet used Fibre Channel can use this opportunity to deploy Fibre Channel storage and other protocols, such as iSCSI, NFS, and CIFS. By using CEE Ethernet as a standard transmission, old devices will be fully utilized, whether for large enterprises or small to medium sized enterprises.

Measures and recommendations

Evaluator Group Consulting recommends that all organizations consider new CEE Ethernet when planning a storage architecture. Based on existing storage products, enterprises should also make arrangements for the use of FCoE.

2010, only the annual IT budget more than millions of dollars of enterprises suitable for investment CEE and FCoE. These enterprise deployments CEE and FCoE will most likely be used to address the problem of hyper-scale server virtualization and the high I/O density. Large-scale applications of CEE and FCoE will appear in 2012 and beyond.

For large enterprises, the deployment recommendations for CEE and FCoE are as follows:

2009-2011 years: Hyper-scale server virtualization requires higher I/O requirements (CEE and FCOE);

2010-2013 years: Server I/O integration, with the integration of CEE to provide additional storage;

After 2012: Convert existing optical storage network facilities to CEE and FCOE architectures.

For small and medium-sized enterprises with low equipment performance requirements, the deployment of CEE and FCoE is expected to follow, not earlier than 2011. For small and medium-sized enterprises that have already deployed fibre Channel vigorously, they will continue to make full use of the existing Fibre Channel for storage system improvement in the future. For Fibre Channel devices, it is recommended to upgrade to 8Gbps in the next two years.

Some SMEs mainly use Ethernet-attached storage, such as Nas and iSCSI. Evaluator Group recommends continued strengthening of standard Ethernet construction. The price of new CEE Ethernet devices is much higher than standard Ethernet devices and is not cost-effective, and the price is expected to converge over the next 2-3 years.

We believe that the future of the world will belong to Ethernet.