Ethernet switch toward network core

Ethernet switches are expanding their applications to the network core. This is mainly from two aspects: one is that Ethernet switches have the function of routers, not even, there are more than three layers of switches; the second is the maturity of the physical layer technology and the Exchange technology makes the Ethernet break through the area of the LAN, and can implement the network across a wide range of regions, such as Single-mode fiber transmission distance can reach more than 40 kilometers, and with the introduction of 10G Ethernet Standard (802.3AE), or even 100G Ethernet, Ethernet backbone network construction is no longer nonsense. This means that Ethernet switches can be built into an access network, a LAN, or a metropolitan area network, or even a WAN. So, as you can imagine, the future of Ethernet switches is bright.

For this reason, the competition in the area of Ethernet switches is particularly fierce. Whether domestic or foreign manufacturers, the goal is to develop software features rich, hardware port density and speed reflects the latest integrated circuit level products. Cisco and 3Com are still the leader in market share, Atrica, Extreme, foundry and Nortel have also introduced technology-leading and performance-friendly products, and Intel and other manufacturers have introduced low-end but superior performance products. Huawei introduced the S8016-type high-end routing switch in 2001, with a back-panel capacity of up to 256Gbps.

The products of each section flourish

Cisco offers a Catalyst series with a full range of switch products, and an important improvement is Cisco's unified use of iOS in its switch series, which facilitates user configuration and management and makes their products more competitive. Cisco's main advantage is that it offers a wide range of products that can generally meet the needs of users.

Atrica has a clear goal: to provide high-speed, profitable optical Ethernet platform to the metropolitan network operators. Atrica that the introduction of sdh/sonet into the metropolitan area network is costly and difficult to manage, while Ethernet is better than sdh/sonet because it is more popular and easier to respond to application needs. The advantage of Atrica is that Ethernet is implemented on fiber, such as 10G Ethernet in DWDM.

Extreme is a company that only advocates Ethernet switches. The company's products have a good policy-based QoS guarantee mechanism, so much acclaim in the industry. Its latest product SummitPx1 can analyze TCP sessions with Gigabit line speed, which can greatly improve the response performance of data centers and Web sites. Extreme's goal is to promote Ethernet switches in the wider range of applications in the metropolitan area network, extreme even believe that the future of the WAN is Ethernet.

Technical observation of Dr. Chen Shaoqiang

The Nortel Passport8600 Series switches provide a 10G Ethernet port. Nortel is also working to turn Ethernet into a metropolitan area network and WAN, citing Ethernet simplicity and low cost. Nortel offers complete optical Ethernet solutions, including Ethernet over Fiber, Ethernet over resilient Packet rings (RPR), Ethernet over DWDM, and Ethernet over SD H et.

3Com copper wire Gigabit in the global market share of nearly 30%, mainly because 3Com products easy to install, management and maintenance, can be said that 3Com of Gigabit Ethernet technology to popularize the work. The 3Com superstack 3 switch 4.9 million Gigabit Ethernet switch product line has been a great success. It can be seen that the 3Com walk is Low-cost, high-performance route.

Foundry from high to low has Bigiron, Fastiron and Netiron several series of products, including Bigiron backplane bandwidth up to 480Gbps. It is worth mentioning that the Netiron product realizes MPLS, which helps to realize the higher level management function of virtual special line and traffic engineering. In addition, the foundry 4-tier Web switch has a high market share.

Intel, Nbase and other vendors also offer lower-end products, typically with gigabit-connected 2/3-tier switches.

Development Youdao

Ethernet switches provide manufacturers generally do not do the bottom of the chip, but the use of chips to provide manufacturers of the core chip. General network processor or ASIC is programmable, three layer and multi-layer exchange is the use of network processor chip microcode programming to achieve.

The software uses proprietary network operating systems (such as Cisco IOS) or commercially available embedded real-time operating systems (such as VxWorks and recently popular embedded Linux) plus proprietary or purchased routing protocols and management software (such as the WindRiver TMS Development Kit), By writing the necessary underlying driver software, you can develop a router-capable switch. In fact, the development of the switch is much more complicated, and the cost of the person is enormous. This is mainly because of the high operating rate of the difficulty of wiring, as well as the network processor microcode programming is very difficult. Therefore, at present, there are still rare products with independent intellectual property rights, and most of them are OEM come.

Advancing to the core of the network

Ethernet switch will be more and more penetrated into the network core domain, so the switch must have the characteristics of the router, can assume the responsibility of unified Business Network. These features include: Improved routing capabilities, support for QoS, support for traffic engineering, support for the road from the table, and satisfaction of operators ' needs. Among them, QoS and traffic engineering for Ethernet is a new attempt, but is completely necessary. Foundry has a good saying: Network engineering is to allocate bandwidth to the load, and traffic engineering, on the contrary, is to allocate the load to bandwidth. Participation in traffic engineering and bandwidth management is an urgent need for increasingly important switches. The problem is that the 802.3 protocol does not specify the concept of data priority, and it is obviously difficult to implement bandwidth management on traditional Ethernet.

The manufacturers ' initial attempts were to use MPLS, such as Foundry's big iron and Extreme's series. Strictly speaking, this does not solve the problem fundamentally (i.e., the physical level), but is a step forward from protocol and software to bandwidth management. The solution to the physical layer should be the task of the chip provider.

On the other hand, Ethernet in self-healing recovery time is not up to the operator's requirements, operators require a millisecond recovery time, and Ethernet self-healing time in about 30 seconds, this gap requires specialized technology to make up. The optical network layer has its own recovery algorithm, the IP layer to provide recovery capabilities, MPLS is the only option. The IP layer's MPLS recovery is accomplished by establishing a standby LSP (Label switching Path) in advance.

Another requirement for operators is profitability, which requires not only low cost of project implementation, but also good billing tool support. For the complete statistical multiplexing of Ethernet, it is necessary to develop the packet statistic function of the outgoing speed, which is a challenge to the line speed of G and 10G.