Agility has become a key initiative for business leaders. Companies need the capability

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1 A ZK Research White Paper Influence and insight through social media Prepared by Zeus Kerravala March 2014 A Guide To Network Virtualization

2 ZK Research Zeus Kerravala A Guide to BYOD Network And Virtualization Collaboration ABOUT THE AUTHOR Zeus Kerravala is the founder and principal analyst with ZK Research. Kerravala provides a mix of tactical advice to help his clients in the current business climate and long-term strategic advice. He delivers research and advice to the following constituents: end-user IT and network managers; vendors of IT hardware, software and services; and members of the financial community looking to invest in the companies that he covers. Introduction: It s Time for the Network to Evolve Agility has become a key initiative for business leaders. Companies need the capability to respond to competitive pressures fast, and to add new applications and services as quickly as possible. This is the primary reason that business agility has become a top initiative for almost every C-level executive and line-of-business manager. The job of creating an agile business has fallen on the shoulders of today s CIOs. The only way to have an agile company is to support the business with agile technology infrastructure. This is why IT leaders have implemented many technologies at the compute and application layer, such as server virtualization, cloud computing and application componentization. However, organizations cannot achieve the necessary level of IT agility without the network reaching a correspondingly higher level of agility. The network has evolved through the different eras of computing and has become a more strategic asset with each successive evolutionary step (Exhibit One, see page 3). The shift to virtual and cloud computing will be the single biggest transition in the history of computing and will impact IT in the following ways: Agile IT will become a reality. Today s business leaders must be able to rapidly change or augment corporate strategy. To accomplish this, CIOs need a dynamic, agile IT infrastructure to support the business. The virtualization of IT resources creates a significantly higher level of IT agility than legacy compute models. 2

3 Exhibit One: Computing Through the Ages Computing Era: Mainframe Computing Era: Internet Computing Connected Endpoints: Tens of Thousands Connected Endpoints: Millions Role of Network: N/A Role of Network: Limited Optimization 1960 to to to Computing Era: Client/Server Computing Era: Virtual/Cloud Computing Connected Endpoints: Hundreds of Thousands Connected Endpoints: Billions Role of Network: Basic Connectivity Role of Network: IT Enabler Strategic Asset Source: ZK Research, 2014 IT will adopt a services model. As IT moves from virtual to cloud computing, it will evolve along the lines of X-as-a-service. This will enable organizations to allocate appropriate resources to the applications and services that require them as per business policy. Consequent- 3

4 ly, businesses can significantly improve resource utilization and maximize investments in infrastructure such as servers and storage. IT silos will disappear. The next IT era will require greater coordination and orchestration of all IT resources from applications through the network. This will require tighter integration 37% of network downtime is caused by human error among IT resources and the operations teams, which will ultimately drive organizations away from traditional IT silos and toward a more unified structure. While the majority of IT today has evolved, the network has yet to change as virtualization has become a bigger part of IT strategy. The architecture used to build networks today is fundamentally the same as it was 20 years ago. If the network is going to become an agile, flexible IT resource, business-centric network virtualization must become a reality. Section II: The Challenge with Legacy Networks The current network architecture used to build enterprise networks and data centers is outdated and cannot enable IT agility. The historical value chain in traditional IT assigned applications the highest value and considered the network to be the plumbing having the least value relative to the rest of the technology stack. Although the network has always been necessary, it ultimately did not play a critical role in the overall performance of the business because most applications were best-effort. Now that IT is shifting to a network-centric model, the following limitations will inhibit a 4

5 company s journey to building an agile business: Built on old protocols: Legacy infrastructure uses the archaic Spanning Tree Protocol (STP) to prevent routing loops and broadcast radiation by disabling ports that are not part of the tree. These disabled ports are made active in the event of a link failure on one of the active ports. This means that up to half of the ports in a network could be in passive mode, leading to a highly inefficient, underutilized network. Static architecture: Network infrastructure is very rigid and optimized for static environments. Network infrastructure provisioning can often have long lead times, and changes often must be made manually on a box-by-box basis. This process can lead to large amounts of human error. ZK Research studies have shown that the largest amount of network downtime, 37%, is due to human error induced during changes (Exhibit Two, see page 6). Not designed for modern compute models: Traditional networks are designed for best-effort traffic, such as and Internet browsing. Today s IT strategies revolve around trends such as real-time collaboration, virtualization and cloud computing. This places the emphasis on the network evolving away from best-effort solutions and toward a network that features guaranteed delivery and low latency. Protocol overlays: With legacy network technologies, the same protocols and features need to be implemented at Layer 2 and then again at Layer 3, creating extra complexity due to the successive overlay of standalone protocols. 5

6 High amounts of latency and insufficient resiliency: Legacy networks are architected with three or more tiers, and traffic is passed through each tier of the network core and then back through each tier. Each of these hops between network devices adds latency and creates points of failure that can impede the performance of mission-critical applications. Exhibit Two: Human Error Is the Largest Cause of Network Downtime Causes of Network Downtime 9% Hardware Failure Power Outage 6% 3% Other 37% Human Error 14% Software Bugs/Error 31% Telco Outage Source: ZK Research,

7 For organizations to leverage the network and create a more agile business, the network must now evolve and itself become a more agile resource. Section III: The Evolution to Network Virtualization Network evolution is long overdue. Server virtualization, mobile computing, the cloud and Network virtualization creates the ability to rapidly scale the network up or down or to create new networks on demand. real-time collaboration have put new demands on the network that legacy designs simply can t meet. This begs the question: If the current network architecture is outdated, what are the characteristics of an agile network? An agile network needs to be significantly less complex than traditional networks. Additionally, the network being put in place today must be future-proofed to be a foundation for forthcoming initiatives. To meet both of these goals, organizations should look to leverage the power of network virtualization. Virtualization is the act of decoupling an infrastructure service from the physical platform on which that service operates. The IT service that is being utilized is not identified with any physical asset; rather, services exist entirely in a logical abstraction layer running within virtualization software. Network virtualization uses network resources and creates multiple logical network segments that run on a single physical network (Exhibit Three, see page 8). The concept of network virtualization isn t new. High availability demands have created the need for the dynamic use of alternative resources. The problem with legacy implementations of network virtualization 7

8 Exhibit Three: Server Virtualization vs. Network Virtualization Application Application Application Workload Workload Workload x86 Environment L2, L3, L4-7 Network Services Virtual Machine Virtual Machine Virtual Machine Decoupled Virtual Network Virtual Network Virtual Network Server Hypervisor Requirement: x86 Network Virtualization Platform Requirement: IP Transport Physical Compute and Memory Physical Network Source: ZK Research, 2014 is that one set of network resources such as links, switches and routers remains idle while waiting for the failure of an active resource. Although this methodology met the challenge of creating dynamic resources, it was highly inefficient because many network resources remain idle most of the time. Network virtualization addresses these issues by abstracting control of the resources and centralizing it in a common control plane. This control plane enables the dynamic allocation of 8

9 the resources based on demand or business policy. Organizations that deploy network virtualization will realize the following benefits: Dynamic network control: Network virtualization offers centralized control over all network resources, with the ability to dynamically provision and reconfigure them. Additionally, through the use of northbound APIs, the applications and compute resources can communicate directly with virtual network resources and automate provisioning to optimize application performance and resource utilization. The overall solution must simplify many of the complexities associated with legacy networks. Lower cost of hardware: There are many ways network virtualization can reduce the cost of hardware, such as lowering hardware costs and providing more efficient bandwidth utilization. Additionally, because of centralized control and automation, many of the operational processes required to manage the network are also greatly reduced, lowering operational expenses. Rapid scalability: Network virtualization creates the ability to rapidly scale the network up or down or to create new networks on demand. This becomes increasingly important as organizations move IT resources to the cloud and shift to an as-a-service model. Section IV: What to Look for in a Solution Business and IT leaders are striving to create business agility. To accomplish this, CIOs have turned to a number of emerging technologies to increase overall IT agility. The requirements 9

10 of cloud, bring your own device (BYOD), virtualization and collaboration are putting unprecedented demands on today s networks. Organizations should adopt network virtualization to enable the levels of network agility and flexibility necessary to align better with the rest of the technology stack. This is a new role for the network. Consequently, network decision makers must shed old-school buying strategies based primarily on brand or vendor incumbency, and instead evaluate network infrastructure based on its ability to support the needs of the evolving enterprise network. However, a full understanding of what to look for in a network solution provider may not be obvious. Enterprises evaluating network virtualization solutions must consider the following: Simplicity of the solution: The goal of network virtualization is to simplify the network architecture and the operational model. This means the overall solution must simplify many of the complexities associated with legacy networks. For example, the network protocols must be unified at Layers 2 and 3 to avoid overlay complexity. Additionally, the solution must provide topology freedom so all services are available whether the virtual network is operating at Layer 2 or 3. Extends beyond the data center: Most network virtualization vendors have solutions targeted at the data center only. Network virtualization can bring tremendous value to points in the network outside the data center including the campus edge, wireless edge and branch offices. Additionally, the solution should span geographically dispersed 10

11 Any solution deployed today must offer sub-second recovery of all network services, including complex ones such as IP multicast. data centers and make them appear as a single enterprise resource. Integrated multi-tenancy: The solution must offer more than just separation of traffic; it must provide full multi-tenant networking. This will allow organizations to keep departmental or tenant networks separated but still offer access to some of the shared services. Additionally, the solution should allow secure zones to be set up across the backbone to isolate different traffic types or groups of users. This is particularly important for businesses operating in environments with regulatory or compliance obligations. Improved network uptime: Any solution deployed today must offer sub-second recovery of all network services, including complex ones such as IP multicast. This is in stark contrast to STP, which would often take tens of minutes before all services were made fully available. Improved scalability: The network must be able to scale beyond the 4,096-VLAN limitation associated with traditional networks. This will provide an excellent foundation for future applications as well as the upcoming wave of mobile devices. Open, standards-based solution: There are many ways for solution providers to meet the challenge of network evolution. Many vendors choose to use proprietary protocols and solutions to develop new products. This can sometimes short-cut development time and allow vendors to get products to market early. However, in the long term, it causes vendor lockin and impairs a customer s ability to choose best-of-breed products in the future. An open, standards-based solution guarantees interoperability with other best-of-breed products and 11

12 ensures a wide variety of choice. For example, there are a number of candidate replacements for STP; but to date, only Shortest Path Bridging (SPB) is based on a standard (IEEE 802.1aq specifications). TRILL and other protocols have yet to be fully standardized, and this uncertainty may lead to interoperability issues in the future. Section V: Conclusion and Recommendations The drive toward business agility is transforming IT at an unprecedented rate. Virtualization Companies should look to migrate away from three-tier designs to a two-tier or even single-tier option when feasible. has already had a significant impact on the software and server industry, and it will have a similar impact on networking because the network plays a critical role in fulfilling on the vision of agile IT. The network is the only pervasive resource, and it connects all IT resources to different users and devices no matter where they are. To do this, though, the network needs to evolve and become a virtual resource that has the same level of flexibility and agility as other enterprise IT resources. Network virtualization will put the network in a position to become the key point of competitive differentiation for organizations as they look to capitalize on the flexibility and cost efficiencies of virtualization. This introduces new requirements for network design and the choice of solution provider. Customers must move decision criteria away from things like market share and vendor incumbency, and focus instead on attributes such as how resilient the network is, to what degree the network simplifies the infra- 12

13 Influence and insight through social media structure, and how it enables virtualization to be used more broadly. With this in mind, ZK Research makes the following recommendations for companies looking to implement network virtualization: Simplify the network architecture as much as possible. Companies should look to migrate away from three-tier designs to a two-tier or even single-tier option when feasible. The less complex the network is, the easier it is to manage and troubleshoot. Stick with a standards-based, open solution. Implementing network virtualization requires a large ecosystem of solution providers. A network built on closed, proprietary technologies may not be able to interoperate with all the necessary ecosystem vendors. A standards-based, open solution guarantees the broadest range of choice for customers. Deploy a no-compromise network, even if that means moving away from your incumbent vendor. Choosing the incumbent vendor often seems like the easy choice because of product familiarity: It s the safe option. However, this often forces IT organizations to make compromises they may regret in the future. The requirements of the network today are significantly different from those of the past; simply going down the path of least resistance might be the wrong choice. Organizations should no longer have to compromise between purchase 2014 ZK Research: A Division of Kerravala Consulting All rights reserved. Reproduction or redistribution in any form without the express prior permission of ZK Research is expressly prohibited. For questions, comments or further information, zeus@zkresearch.com. price, resiliency, power efficiency and feature set. Choose the vendor that best supports your network virtualization initiatives, and do not compromise on any features needed to fulfill on the vision of agile IT. 13