DATA CENTER FABRIC FOR CLOUD NETWORKS

Table of Contents Executive Summary........................................................................................................ 3 Introduction................................................................................................................ 3 Technology Drivers......................................................................................................... 3 Economic and Business Drivers............................................................................................. 4 Challenges to Building the Cloud-Ready Data Center Fabric................................................................. 5 Fabric The Ideal Network Architecture..................................................................................... 7 Preparing for the Next-Generation Data Center Fabric....................................................................... 8 Conclusion................................................................................................................. 8 About Juniper Networks.................................................................................................... 9 Table of Figures Figure 1: Typical data center network....................................................................................... 5 Figure 2: Server-to-server traffic............................................................................................ 6 Figure 3: Data center fabric................................................................................................. 8 2 Copyright 2009, Juniper Networks, Inc.

Executive Summary Legacy network architectures are inhibiting today s data centers as IT organizations continue the struggle to keep up with the burgeoning growth of Internet-enabled application services, servers, storage infrastructures and network traffic. The impact of legacy approaches on modern data centers aggravates management complexity and escalates operating costs, while offering little performance gain. Juniper Networks is committed to advancing the economics of high-performance networking by providing IT organizations with a cloud-ready foundation that liberates next-generation data centers from the constraints of legacy architectures. It starts with a vision for the ultimate in simplification - a single data center fabric one that is flat, nonblocking and lossless which delivers unprecedented scale, performance and simplicity. This ubiquitous fabric has the flexibility to support fully converged and virtualized data centers, seamlessly integrating storage, high-performance computing and networking environments. Perhaps most important, this fabric will prove to be instrumental in driving down the cost and complexity of management and data center operations well into the future. Introduction The Internet not only altered the way people and devices interconnect, but set in motion a transformation in application architectures and the underlying compute and storage infrastructure that reside behind the Internet and in the modern data center. Almost every facet of IT has undergone dramatic change since the Internet was opened to commercial use in 1995. The data center has been the foundation for this change. Client-server applications gave way to applications based on service-oriented architectures (SOAs), which in turn drove the commoditization of servers. As servers were commoditized, the inefficient model of one application per server, power and space concerns, and the need to curb capital expenditures drove the adoption of server virtualization as well as the separation and virtualization of storage. These changes driven by both technological and economic forces had a lasting impact on data centers. Technology Drivers The influx of Web-based services across the Internet was triggered by the convergence of four key technology drivers: The availability of a fast, reliable IP network with ubiquitous access across the Web. The development of a stateless Web browser to simplify client provisioning and management. The digitization of content and resulting ability to deliver content over a network. Beginning with simple text and e-mail, today, it extends to nearly every form of data and communications, including voice, music, photographic imaging and video. The forward momentum of Moore s Law 1, which continues to reduce the cost of computing and increase the speed of networks. The advent of languages such as JAVA, as well as new middleware and software development tools, unleashed a torrent of new applications that were built with SOAs and enhanced Web 2.0 interfaces. This delivered unprecedented levels of application and service scalability and flexibility, which placed new pressure on the compute, storage and network infrastructure. It quickly became apparent that these changes in application design would necessitate changes to the underlying compute infrastructure. The number of installed servers and storage arrays to handle these applications and data skyrocketed due to commoditization and standardization. This was the start of a growing need to centralize and consolidate the infrastructure. In the days of client-server applications, the computing infrastructure was distributed closer to workgroups to reduce latency and improve performance. However, as the Internet build-out accelerated, it leveraged faster network speeds, making it possible to locate the compute and storage infrastructure remotely, away from users, while still delivering acceptable performance. With a centralized infrastructure now within the realm of possibility, the distributed computing trend was thrown into reverse. A centralized approach eases management and scalability challenges, and the pooling of resources leads to a lower total cost of ownership. Servers and storage moved back into data centers. Multiple smaller data centers were consolidated in fewer, larger data centers. Soon, enterprise data centers had thousands of servers and petabytes of storage, while large service providers built mega data centers with tens of thousands servers. 1 According to Moore s Law, the number of transistors on a chip roughly doubles every two years. As transistor counts climb, so does the ability to increase device complexity and integrate many capabilities onto a chip. Copyright 2009, Juniper Networks, Inc. 3

As data centers continue to grow the need to power and cool the infrastructures drives up the cost of space, and capacity expansion introduces a new set of challenges. For example, power delivery limitations can impede the size and location of new data centers. As a result, newer data centers are often built in unpopulated areas next to major power sources, such as the Columbia River. Finally, as more power is consumed, more heat must be dissipated from data centers, which makes the cost of cooling a significant portion of the operating budgets. The final part of the infrastructure is the network, the foundation of the data center. In addition to interconnecting equipment, it moves data within and between data centers, as well as to users and client devices. The network has evolved with faster, denser hardware that has increased bandwidth and reduced latency. What has not changed significantly in the last 15 years is the underlying architecture of the data center network. This area is ripe for change. Economic and Business Drivers In addition to changes in the underlying technology, the Internet has driven three significant economic and business opportunities: (1) building better connections, (2) enabling new services and (3) driving economies of scale. First, the Internet gave businesses the ability to make better connections with customers, suppliers, partners and employees. Services were improved, customer awareness was raised, customer satisfaction went up and revenues increased. Businesses also enhanced productivity, enriched decision-making and streamlined supply chains. All this led to the development and deployment of richer applications services that placed greater pressure on data center networks. The second opportunity provided by the Internet is a new model to deliver or acquire products and services. IT hardware and software used to be sold and physically delivered to end customers. With the emergence of cloud computing, that same hardware and software are delivered as services over the network. Rather than buying them, consumers can subscribe to services on an on-demand basis, paying only for what they need, when they need it. A wealth of these services is currently available online, and they can be organized into three general categories: Application services. Known as software as a service (such as Salesforce.com, Google Docs, Twitter and Microsoft Office Live), they provide application, content and process capabilities. They also include services like payroll, planning and collaboration. Platform services. These services incorporate middleware and software development tools and frameworks, such as Amazon Web Services. Infrastructure services. These shared compute, storage and network services (such as Amazon EC2 and S3) replace or augment in-house and hosted resources. They also include disaster recovery services, long-term data storage and supplemental capacity for software release testing and simulation. As newer and more innovative services go online, they are faced with unprecedented scale challenges. How do you build out an infrastructure to support millions or tens of millions of users? Answering this question has led to some of the technological innovations previously mentioned. Again, there is a need for the data center network to evolve to meet this challenge of scale. The third business opportunity driven by the Internet is the ability to achieve economies of scale as the scale of data centers and their infrastructures increase. This is in addition to the economies of chip density and functionality served up by Moore s Law. One of the basic tenets of cloud computing is that the infrastructure is consolidated into large, standardized pools of dynamic resources that are shared across multiple applications, users and consumers. Through abstraction and virtualization, resources are dynamically allocated to handle changing capacity requirements. Exhibiting exceptional elasticity, this approach achieves economies from scale and standardization, while keeping all data flows securely partitioned. Leveraging the economies of scale of cloud-computing infrastructures is a key element in the business model of public cloud service providers. Greater scale and economies let providers deliver services at attractive price points while still generating a profit. Consequently, even organizations that are not currently involved in the production or consumption of cloud services will benefit from employing the concepts behind cloud infrastructures to drive economies in their data centers. The challenge lies in deploying and managing infrastructures at a larger scale. 4 Copyright 2009, Juniper Networks, Inc.

Challenges to Building the Cloud-Ready Data Center Fabric Today almost all architectures for data center networks are multitiered tree designs built from three, four or more tiers of switching and routing. These tiers include: An access layer to connect servers and other devices. An aggregation layer to provide connectivity fan-out. A core layer to interconnect aggregation clusters. A routing or data center edge layer to interconnect network segments within a data center, or connect a data center to other data centers or to a WAN. Data Center Edge (Routing Layer) Core Layer Security Appliances Aggregation Layer Access Layer Servers Storage Area Network Storage Figure 1: Typical data center network One notable challenge with today s data center networks is that they have grown organically over time, driven by near-term needs rather than the optimization of the data center as a whole. This is especially evident in the deployment of security appliances, which were initially deployed to address the security requirements of specific applications. As the number of applications and interactions increase, the shortcomings of this organic approach are exposed. As a result, security appliances are scattered about the network. Some are overutilized and cause bottlenecks, while others are underutilized. In addition, certain data traffic is subject to the scrutiny of an excessive security process while other traffic remains vulnerable. Complicating matters, each security appliance is an incremental point in the network and must be managed. Copyright 2009, Juniper Networks, Inc. 5

Another challenge is that data centers often consist of two or more networks, each built using different technologies that solve different problems. For example, Ethernet offers client-to-server and server-to-server connections, while Fibre Channel connects servers to disks and tape devices in a storage area network. Finally, technologies such as Infiniband offer lowlatency, server-to-server communication required in high-performance computing environments. Traditionally, the network, which is the foundation of the data center infrastructure, had to exhibit the following characteristics. Fast to support the low-latency, server-to-server traffic, which is characteristic of SOA and Web 2.0 architectures, and meet the bandwidth requirements of a digital world. Secure enough to protect critical data and computing infrastructures. Reliable enough to meet the demands for 24x7 operations. To begin meeting the challenges of the cloud-ready data center, the new network must be: Scalable to interconnect all the devices in a data center, which becomes more critical as data centers and resource pools become larger. Simple enough to be managed efficiently in the real world and to reduce operational errors that lead to outages, vulnerabilities and poor application service levels. Shared to allow virtualization of the data center infrastructure, as well as to enable the convergence of multiple networks into a single, unified system. This is the key to delivering efficiency and elasticity. Unfortunately, as IT steps up to meet these challenges, data center networks remain inhibited by their current architectures. Continuing to build out data center networks with autonomous switches that are arrayed in legacy tree structures will create deeper management and performance deficiencies with potentially disastrous consequences from a cost standpoint. The disadvantages of current network architectures include: Spanning Tree Protocol (STP) Unfortunately, STP is prevalent in most data center networks today. Due to its complexity, STP should be minimized or eliminated, resulting in lower operational and capital costs. Inefficiency Another problem with tree structures is that up to 50% of switch ports and thus the cost of the network connect switches between tiers of the tree rather than achieving the primary goal of connecting servers and storage to the network. Latency Data packets that move from switch to switch in a tree are decoded and encoded at every hop. The more devices and layers traversed, the greater the latency. As shown in Figure 2, traffic that moves east-west (sideways) between servers in a tree must first move north (up) and then south (down), adding even more latency. This also applies to serverto-storage traffic. In data centers with SOA and virtualized server environments, up to 80% of traffic moves in an eastwest flow, and this traffic is very latency sensitive. Server to Server Traffic North South Traffic East West Traffic Server Figure 2: Server-to-server traffic 6 Copyright 2009, Juniper Networks, Inc.

Nonscalable Management complexity increases exponentially as more devices are added to the network. This is a huge impediment in environments where enabling scale is the key to efficiently delivering application services. To limit complexity, data center networks traditionally used physical segmentation, which impedes the ability to build large, shared resource pools and achieve the desired efficiencies and agility. Disparate networks Data centers generally contain multiple networks (such as Ethernet, Fibre Channel and Infiniband) with each using different technologies to solve different problems. This diversity increases management and capital costs. Fabric The Ideal Network Architecture The best way to envision the ideal network architecture is to consider the behavior of a single Ethernet switch. A single Ethernet switch is fast and simple to manage, and presents a flat, any-to-any network. Each device connected to the switch is connected to every other device, and Ethernet packets are processed only once. It also eliminates internal congestion and the need to run STP within the switch. Finally, the switch provides one central point for provisioning and administration. Unfortunately, no single switch today can scale to meet these demands or handle the growing capacity requirements of cloud-ready data centers. Furthermore, having one switch in the network creates a single point of failure, falling short of reliability requirements. This is why most data centers aggregate multiple switches into a tree structure, despite its inherent shortcomings. A better alternative for cloud-ready data centers is to employ a scalable fabric. A fabric is a set of devices that act in concert to behave as a single switch. It can grow to interconnect all the devices in a data center while maintaining the simplicity of a single switch. This fabric must have the following attributes: Scalable The fabric connects all server, storage, security, routing and application devices in the data center. It satisfies current networking needs and scales to support tens of thousands of physical ports and hundreds of thousands virtual ports. The fabric also accommodates capacity in a simple, linear manner to preserving existing investments. Fast The fabric supports 10, 40 and 100 GbE access speeds. Presenting a single tier of switching, Ethernet packets are decoded and encoded only once to reduce latency to traverse the data center by an order of magnitude. It also offers very high bisectional bandwidth that scales with the number of ports supported. Congestion-free It is imperative for the fabric to leverage a nonblocking, any-to-any architecture. This eliminates congestion within the fabric, which reduces latency and ensures consistent performance under load. It also simplifies the ongoing operation of the fabric. Converged A congestion-free fabric is lossless so that all traffic in a data center can be converged onto a single network. Consequently, the fabric must support Ethernet, Fibre Channel over Ethernet and native Fibre Channel packets and frames. Flexible Connecting data center resources to a scalable, flat fabric eliminates the need for physical boundaries and segmentation. Virtual partitioning can then be deployed to create security and administration zones and broadcast domains. It allows the network to be easily reconfigured to meet the changing needs of the data center and provide greater organizational agility. Secure Inherent in the fabric, security services are applied dynamically to network traffic as needed. These security services are arranged in resource pools and shared across the data center network fabric to achieve higher utilization and greater elasticity. Reliable Reliability is an essential component of the data center fabric. To ensure carrier grade reliability, the fabric is built according to the highest standards, presents no single point of failure and enables in-service software upgrades and reconfiguration. Simple The fabric performs as a single logical switch. This eliminates the need for STP, congestion management and quality of service within the fabric. It also simplifies management and administration while dramatically reducing associated costs. Efficient Hardware in the fabric is substantially reduced by eliminating extraneous devices in tree structures and simplifying the backbone. In addition to cutting capital costs, this reduces space, power and cooling requirements, as well as ongoing support and maintenance costs. Interconnected The fabric needs to support interconnections within and beyond a data center to the rest of the world with routers that provide edge services. Copyright 2009, Juniper Networks, Inc. 7

Data Center Edge Fabric Security Services Servers Figure 3: Data center fabric Storage Preparing for the Next-Generation Data Center Fabric By rethinking the network from the ground up, Juniper Networks is ready to meet the challenge of delivering the nextgeneration data center fabric with the Stratus Project, which was announced in early 2009. Through this initiative, Juniper is developing a single, cloud-ready data center fabric that offers a quantum jump in scale, performance and simplicity plus the flexibility to support fully converged and virtualized data centers. The fabric born out of this initiative will be augmented by Juniper s extensive routing, switching and security solutions, which provide unparalleled scale, simplicity, virtualization and security, while supporting a broad range of services. All Juniper routers, switches and security products run the same single version of the Juniper Networks Junos Software for simpler feature deployments and upgrades, as well as a consistent implementation of control plane features across the data center infrastructure. This reduces complexity in high-performance networks to increase availability and deploy services faster with a lower total cost of ownership. What sets Junos apart from other network operating systems is the way it is built one operating system delivered in one software release train and with one modular architecture. The consistent operating environment of Junos increases productivity and improves the availability, performance, and security of application services. Conclusion The era of legacy data center architectures is ending. Just as other areas of the data center have evolved to meet the demands of an Internet-enabled world, the time has come for networks to take a significant leap forward into cloud computing. By rethinking legacy data center architectures, Juniper Networks will enable IT organizations to build a single ubiquitous fabric that is faster, more reliable and simpler to manage. Flat, nonblocking and lossless, this network fabric will have the scale and flexibility to meet the needs of small and medium-sized data centers, as well as large mega data centers for years to come. With Juniper s vision for the next-generation data center fabric providing the foundation for cloud networking, IT organizations can adapt quickly and cost-effectively to changing business requirements. All network resources routing and security services, storage, appliances and servers are dynamically allocated without compromising performance. As a result, mission-critical applications can be provisioned rapidly while maintaining optimum service levels. 8 Copyright 2009, Juniper Networks, Inc.

About Juniper Networks Juniper Networks, Inc. is the leader in high-performance networking. Juniper offers a high-performance network infrastructure that creates a responsive and trusted environment for accelerating the deployment of services and applications over a single network. This fuels high-performance businesses. Additional information can be found at www.juniper.net. Corporate and Sales Headquarters APAC Headquarters EMEA Headquarters To purchase Juniper Networks solutions, Juniper Networks, Inc. 1194 North Mathilda Avenue Sunnyvale, CA 94089 USA Phone: 888.JUNIPER (888.586.4737) or 408.745.2000 Fax: 408.745.2100 www.juniper.net Juniper Networks (Hong Kong) 26/F, Cityplaza One 1111 King s Road Taikoo Shing, Hong Kong Phone: 852.2332.3636 Fax: 852.2574.7803 Juniper Networks Ireland Airside Business Park Swords, County Dublin, Ireland Phone: 35.31.8903.600 Fax: 35.31.8903.601 please contact your Juniper Networks representative at 1-866-298-6428 or authorized reseller. Copyright 2009 Juniper Networks, Inc. All rights reserved. Juniper Networks, the Juniper Networks logo, Junos, NetScreen, and ScreenOS are registered trademarks of Juniper Networks, Inc. in the United States and other countries. Junos is a trademark of Juniper Networks, Inc. All other trademarks, service marks, registered marks, or registered service marks are the property of their respective owners. Juniper Networks assumes no responsibility for any inaccuracies in this document. Juniper Networks reserves the right to change, modify, transfer, or otherwise revise this publication without notice. 2000327-001-EN Oct 2009 Printed on recycled paper Copyright 2009, Juniper Networks, Inc. 9