1. WHITE PAPER
DIffERENTIATED
ARCHITECTuREs foR
THE DATA CENTER
Key factors Driving the Need to Change Architecture in
Today’s Data Center
Copyright © 2011, Juniper Networks, Inc. 1

2. WHITE PAPER - Differentiated Architectures for the Data Center
Table of Contents
Executive summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Making Best use of All Resources and Becoming Cloud-Ready . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Cost Centers or Profit Centers—Different solutions for Different Data Center Needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
faster, simpler, and Cost Effective – The Juniper Data Center Advantage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Juniper’s 3-2-1 Data Center Network Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The IT Data Center Becomes simpler and More Cost Effective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
The New Network Is Reduced to Two Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
The Production Data Center Is faster and More scalable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Conclusion—Differentiation for the Data Center with Qfabric—It’s one Big switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
About Juniper Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table of Figures
figure 1: Juniper’s 3-2-1 data center vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
figure 2: Legacy three-tier network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
figure 3: simplified two-tier network architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
figure 4: Juniper’s fabric-based production data center network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
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3. WHITE PAPER - Differentiated Architectures for the Data Center
Executive Summary
A number of recent trends—including mobility, new application architectures, and evolving types of applications—are driving
divergence between campus and data center architectures. Evolving needs require different architectures, making the same
network does all design a thing of the past. The data center network now requires a very different architecture from the
campus network in order to successfully deliver applications.
The situation within the data center is similar. Evolving application requirements, the emergence of storage convergence and
virtualization, cloud security threats, and the growing need to interconnect data centers all demand different designs and
architectures to achieve different goals for different types of data centers.
At the center of these changing requirements are the applications themselves. It starts with service-oriented architectures
(soAs), which require conversations between multiple servers and storage devices in order to complete a task, completely
changing the way traffic has typically traversed the data center. These changes have reoriented traffic flows within the
data center, moving from predominantly north-south (client-server) to east-west (server to server). unfortunately, existing
multitiered network architectures in the data center, which were created to enhance security and scale for north-south traffic
patterns, have become inhibitors of effective application activity in the new east-west model. soA requirements in turn drive
the need for changes in storage, Layer 2 domain scale, and server utilization.
Recognizing these requirements for change, Juniper delivers a complete product set to implement the best possible
architectures for today’s evolving data center, centered around a simplified, cost-effective 3-2-1 network architecture and its
revolutionary Juniper Networks® Qfabric™ technology.
Introduction
Making Best Use of All Resources and Becoming Cloud-Ready
The promise of the cloud for data centers is that it converts all of the compute and storage capacity into pools of resources
which can be dynamically allocated and shared. shared resources are more efficient than resources in silos. With cloud
computing, applications can be added quickly and they function more efficiently.
Juniper has developed a vision for the evolution of the data center that takes these changes into account, delivering a
strategy for making all data centers cloud-ready. By following the Juniper vision, all types and scales of data centers can
enjoy the advantages of virtualization, storage optimization, ubiquitous security, and secure, WAN-extended L2 domains—all
orchestrated from a central point of management.
Cost Centers or Profit Centers—Different Solutions for Different Data Center Needs
Whether CIos are managing a data center which runs the operational side of the business (IT data center) or a data center
which produces revenue (production data center), Juniper has a vision for evolving these entities to a cloud-ready state.
IT data centers, which provide connectivity and business application support, are cost centers that require control and
stability. Production data centers, on the other hand, are profit centers and require state-of-the-art technology and the
highest possible performance.
IT data centers almost exclusively use 100-400 1GbE servers. They have separate storage Area Networks (sANs) which
provide fibre Channel (fC) storage. Production data centers typically have 10GbE servers and are actively pursuing strategies
for integrating their storage with their compute resources through the same Ethernet network. Choices of simplified network
architectures from Juniper enable both the IT and production data centers to become cloud-ready.
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4. WHITE PAPER - Differentiated Architectures for the Data Center
Faster, Simpler, and Cost Effective – The Juniper Data Center Advantage
Every data center begins its evolution to a cloud-ready state from a different place. The vast majority of customers currently
have three-tier data center network architectures, compliments of vendors who have a vested interest in selling as many
switches as possible. The Juniper 3-2-1 data center network architecture, on the other hand, enables customers to migrate
from this highly inefficient three-tier network architecture to a more streamlined two-tier or even one-tier network, depending
upon requirements for scale and 10GbE.
Legacy three-tier Juniper two-tier Juniper’s data
3. data center 2. data center 1. center fabric
W Up to 75% of tra c E
W Up to 75% of tra c E
Figure 1: Juniper’s 3-2-1 data center vision
Juniper’s 3-2-1 Data Center Network Architecture
Juniper’s prescription for building a cloud-ready data center network requires three steps:
• Simplify the network with a 3-2-1 data center architecture: By consolidating siloed systems and collapsing or eliminating
inefficient tiers using a single network fabric running a single network operating system, users can reduce the number of
devices, shrink their operational footprint, reduce complexity, simplify management operations, and improve application
performance.
• Share the resources: Virtualize network resources to segment the network into simple, logical, and scalable partitions
for various applications and services, while using fabric technology to ensure seamless connectivity to those resources
regardless of their location. Privacy, flexibility, high performance, and quality of service (Qos) remain primary goals. such
sharing results in greater agility for multiple users, applications, and services.
• Secure the data flows: Integrate dynamic security services into the network to provide security scale, threat visibility,
and enforcement. These comprehensive services secure data flows across both physical and virtual environments, while
leveraging centralized orchestration to dramatically simplify the enforcement of dynamic, application-aware, and identity-
aware policies, ultimately ensuring better application availability and network performance.
It is also important to automate network operations at each step with an open, extensible software platform. This reduces
operational costs and complexity, enables rapid scaling, minimizes operator errors, and increases reliability through a single
network operating system. A powerful network application platform with innovative applications enables network operators
to leverage Juniper or other third-party applications that simplify operations and scale application infrastructure to improve
operational efficiency.
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5. WHITE PAPER - Differentiated Architectures for the Data Center
The IT Data Center Becomes Simpler and More Cost Effective
The existing three-tier network architecture presents several problems—replication of security at every aggregation point,
increasing latencies due to multiple aggregation switches separating servers, using protocols to prevent loops, and increasing
the number of IP addresses to manage. This architecture does not scale gracefully, and it is costly to maintain.
using technologies such as virtual private LAN service (VPLs) network virtualization on Juniper Networks® MX series 3D
universal Edge Routers, and Virtual Chassis technology on Juniper Networks EX series Ethernet switches, Juniper flattens
data center networks by reducing them from three layers to two. EX series switches help collapse this three-tier architecture
into two layers using Virtual Chassis technology at the access and core layers. The intermediate, aggregation layer can be
removed, with tremendous cost savings.
3 2 1 The legacy network, 3 tiers.
Ethernet Core Layer
Aggregation Layer
Access Layer
Servers NAS FC
Storage
FC
FC SAN
Figure 2: Legacy three-tier network
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6. WHITE PAPER - Differentiated Architectures for the Data Center
The New Network Is Reduced to Two Layers
By following the Juniper strategy of simplify, share, and secure, it is possible to transform this legacy architecture into a much
more efficient system, at a much lower cost. This section will discuss the methods used to accomplish this by examining
each element of the approach.
3 2 1 Today, move to 2 tiers.
MX Series
EX8200/ Core Layer
MX Series
SRX5800
EX4200/ QFX3500
EX4500
Virtual Chassis
GbE 10GbE
Configuration
Servers NAS FC
Storage
FC
FC SAN
Figure 3: Simplified two-tier network architecture
Simpler Switching Infrastructure
The switching infrastructure can be greatly simplified by creating a two-tier network fabric using Juniper’s Virtual Chassis
technology, available on its EX series Ethernet switches. Virtual Chassis technology allows multiple interconnected switches
to operate as a single, logical device, providing a scalable solution that eliminates the need for three switching tiers and
removing the barriers to rapid east-west traffic required by modern applications. At the L2 edge where servers attach to the
network, Virtual Chassis technology creates an access layer fabric by joining multiple individual devices as a single switch
sharing a single configuration file and operating system, thus removing the need to manage each individual switch and
replacing all of them with one management object. At the L3 aggregation layer, Virtual Chassis technology provides a highly
resilient fabric for the core by condensing multiple switches into one managed entity, eliminating loop-related issues in the
access network.
Efficiently Connected Across the WAN
At the data center’s edge where connections to other data centers and networks occur over the WAN, the Internet, or a
partner’s network, the number of deployed devices can be consolidated into fewer, more agile, and more scalable devices
with Juniper solutions. This consolidation simplifies the management and control of network connections while lowering
operational costs. Juniper Networks M series Multiservice Edge Routers and MX series 3D universal Edge Routers are
powerful, reliable, and the industry’s most scalable solutions for intelligent edge and inter-data center mobility. Multiple data
centers can be connected via L2 extensions over VPLs, a standards-based interface for long reach connectivity.
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7. WHITE PAPER - Differentiated Architectures for the Data Center
Consolidated Security
Network-based security services—intrusion detection and prevention, encryption, and application monitoring—can be
consolidated into highly scalable dynamic security platforms to reduce security sprawl. The Juniper Networks sRX series
services Gateways can reduce previously siloed security platforms by a ratio of 5:1, enabling rapid provisioning and simplified
operation of multiple security controls for dynamic scaling of security services across physical and logical platforms. The
sRX series meets the network and security requirements of data center hyper-consolidation, rapid managed services
deployments, and aggregated security solutions by providing a unified and scalable platform with a smaller footprint.
The Production Data Center Is Faster and More Scalable
3 2 1 QFabric
MX Series
Access Layer
SRX Series
Servers NAS FC Storage
Figure 4: Juniper’s fabric-based production data center network
Production data centers are faced with the challenge of having to increase performance while increasing scale. since the
most efficient way for resources to interact is to reduce the number of hops between them, the ideal next-generation network
architecture would directly connect all processing and storage elements in a flat, any-to-any connectivity-based network
fabric. optimized for performance and simplicity, this next-generation architecture would address the latency requirements
of today’s applications, eliminate the complexity of legacy hierarchical architectures, scale elegantly, and support
virtualization, cloud computing, convergence, and other requirements for the next-generation data center.
Juniper Networks Qfabric™ technology delivers this revolutionary design by creating a single tier network that operates—and
is managed—like a single, logical, distributed switch. Consisting of edge, interconnect, and control devices—all running the
Juniper Networks Junos® operating system—Qfabric technology combines the low latency, flat architecture, and operational
simplicity of a single switch with the scalability and resiliency of a fabric. The result is an innovative approach that unleashes
the exponential power of the data center, delivering any-to-any connectivity that reduces complexity and lowers capital,
management, and operational expenses. In addition, by optimizing application performance and supporting virtualization,
convergence, cloud computing, and other key technologies, Qfabric technology makes the entire data center more efficient.
since the Qfabric solution behaves like a single switch, it operates with the MX series solutions to share and the sRX series
solutions to secure in the same efficient fashion as the two-tier data center.
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8. WHITE PAPER - Differentiated Architectures for the Data Center
Switching
By giving organizations high performance, simplicity, and scalability while lowering capital and operational expenses, a
fabric-based data center architecture eliminates the need for IT to trade off one capability for another. Whether a company is
looking to re-architect its data center to sell cloud services, streamline service delivery, or bring new products to market more
quickly, a fabric-based network architecture can help them get the most from their investments in virtualization, soA, and
other data center technologies.
Routing
Data center fabrics must connect to the WAN and to other parts of the corporate network in order to connect users with
applications. Juniper routing platforms deliver the efficiency and scale to create data center to data center links across the
private or public wide area network. The ability to add new links efficiently to existing platforms provides the fastest possible
time to bring up new services from multiple, distributed data centers.
Security
By consolidating multiple functions into a small footprint, Juniper security platforms can provide tremendous cost savings
over traditional security models. services such as application-aware denial of service (Dos), stateful firewall, and intrusion
detection and prevention systems (IPs) are consolidated on a security platform and can be enforced from the physical
network to the virtual machine hypervisor for the widest possible range of coverage.
Automation
Juniper is the only major networking systems company to offer the same operating system on all of its platforms. This
improves the speed at which new devices can be added, while reducing the overall complexity and cost of management.
Table 1: Summary of Juniper Technologies and Benefits
PRoDUCT TyPE TEChNoLogy BENEFIT
switching fabric • Easier to manage, improves reliability, reduces cost
• Virtual Chassis • speed of applications, fastest scale of server farms
• Qfabric technology
Routing • MPLs/VPLs • scale and efficiency
• Virtual Chassis • Easier to manage, improves reliability
security • Consolidated security services • space and cost savings with more services
• Hypervisor firewall • Comprehensive virtual security
Automation • Junos os • Reduces time to deploy and manage, decreases
• Juniper Networks Junos space operations costs
• Provides a single control point for all platforms
Conclusion—Differentiation for the Data Center with QFabric—It’s one Big Switch
To create a simple single-tiered data center network, Juniper drew inspiration from existing switch designs, determining that
the best way to address data center complexity was to make the network itself behave like a single distributed switch.
Inside every switch is a fabric—a mesh that is completely flat (not hierarchical, like a multitiered tree network) and provides
any-to-any connectivity between ports. Qfabric technology extends this concept of a switch fabric and scales it beyond a
single device to the entire data center network. When this fabric design is applied, it retains a level of simplicity by allowing
multiple physical switches to behave as, and be managed like, a single logical device. Management and operational expenses
are an order of magnitude lower than with traditional network architectures.
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9. WHITE PAPER - Differentiated Architectures for the Data Center
A network fabric design enables any-to-any connectivity, where every device is a single hop away from every other device.
Qfabric technology also greatly simplifies the network architecture by eliminating unnecessary switch layers and the
corresponding switch-to-switch interactions. In addition, because the Qfabric solution functions as a single device, there
is no need for shared network protocols like spanning Tree, since the configuration and management of the network fabric
does not need to be exposed to the customer. Consequently, network management and operations are greatly simplified,
and performance improves even if the network scales from tens of ports to tens of thousands of ports. servers, storage, and
other data center devices can be connected to the fabric seamlessly because of the fabric design’s high degree of scalability.
optimized for performance and simplicity, Juniper Networks Qfabric technology addresses the latency requirements
of today’s applications, eliminates the complexity of legacy hierarchical architectures, scales elegantly, and supports
virtualization, cloud computing, convergence, and other requirements for the next-generation data center.
About Juniper Networks
Juniper Networks is in the business of network innovation. from devices to data centers, from consumers to cloud providers,
Juniper Networks delivers the software, silicon and systems that transform the experience and economics of networking.
The company serves customers and partners worldwide. Additional information can be found at www.juniper.net.
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Copyright 2011 Juniper Networks, Inc. All rights reserved. Juniper Networks, the Juniper Networks logo, Junos,
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