Virtualization Changes Everything. WOC 2.0: The Era of Virtual WAN Optimization Controllers

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1 Virtualization Changes Everything WOC 2.0: The Era of Virtual WAN Optimization Controllers January 30, 2012

2 Introduction While ensuring acceptable application delivery has always been important, it historically wasn t a top of mind issue for the majority of IT organizations. That changed several years ago when IT organizations began to develop a concerted focus on application delivery in large part to respond to the performance challenges that were associated with supporting applications that were delay sensitive and/or chatty, as well as supporting large file transfers between headquarters and branch offices. One of the primary ways that IT organizations responded to these performance challenges was by deploying WAN Optimization Controllers (WOCs). In the vast majority of instances, WOCs were implemented as a stand-alone hardware-based device. Throughout this white paper the application delivery challenges and the WOC solutions of the last several years will be referred to as the WOC 1.0 era. Driven in large part by the adoption of virtualization, IT organizations are now facing a new wave of emerging application delivery challenges. For example, the successful adoption of desktop virtualization is one of the factors that will require IT organizations to support a dramatic increase in delay sensitive WAN traffic. Virtualization, however, is also enabling some significant new application delivery solutions. For example, as explained below, in addition to the traditional, stand-alone hardware based WOCs, IT organizations can now also implement virtual WOCs (vwocs) that offer IT organizations a number of advantages. Throughout this white paper the emerging application delivery challenges and the associated WOC solutions will be referred to as the WOC 2.0 era. As part of the research for this paper, two IT professionals whose companies have adopted vwocs were interviewed. One of the interviewees is Will Hosek, VP of IT at SurePrep, a U.S.- based tax preparation service provider. The other interviewee is Kees Jan Mink, General Manager and CTO at Carrier to Carrier Telecom BV (C2C), a Netherlands-based provider of both satellite and terrestrial solutions as well as IaaS Cloud Services. C2C is a fully owned Globecomm company. The goals of the interviews were to understand the reasons behind their decision to implement vwocs and to identify the criterion that they used to evaluate vwocs. Network and Application Optimization Challenges As previously noted, some of the performance challenges that were associated with the WOC 1.0 era were supporting applications that were delay sensitive and/or chatty. VoIP is an example of an application that is widely deployed and whose performance is highly sensitive to delay, jitter and packet loss. As illustrated in Figure 1, a chatty application or protocol requires hundreds of round trips to complete a transaction. 2

3 Figure 1: Chatty Application To exemplify the impact of a chatty protocol or application, assume that a given transaction requires 200 application turns and that the round trip delay of the WAN on which the application will be deployed is 100 milliseconds. For simplicity, the delay associated with the data transfer will be ignored and only the delay associated with the application turns will be calculated. That delay is 20 seconds. That much delay would at best be an irritant to the users of the application, and at worst cause the application to not be usable. The challenges of the WOC 2.0 era include all of the challenges of the WOC 1.0 era, plus some additional ones. For example, while supporting VoIP remains a challenge for the majority of IT organizations, The 2011 Cloud Networking Report 1 contained the results of market research that indicates that over the next year that almost 80% of IT organizations will increase their use of video, and that in many cases the increased use of video will be substantial. The same market research demonstrated the growing interest that IT organizations have in desktop virtualization and concluded that over the next year that the percentage of IT organizations that haven t implemented any desktop virtualization will be cut roughly in half. SurePrep is an example of a company that has made a significant deployment of desktop virtualization. According to Hosek, SurePrep implemented desktop virtualization for security reasons but that it is very challenging to get good performance when the devices are thousands of miles apart from each other. He added that the protocol that their desktop virtualization solution utilizes is encrypted and that There isn t a lot that a WOC can do to optimize the performance of RDP, but we were able to get a 30% improvement in performance just based on the ability of our WOCs to re-sequence packets. In addition to adopting virtualization, IT organizations are also adopting varying forms of cloud computing such as Infrastructure-as-a-Service (IaaS). As pointed out in The 2011 Application and Service Delivery Handbook 2, the market for IaaS solutions is expected to grow from just under $4 billion in 2011 to just over $10 billion in That handbook also stated that a variety of data center initiatives are also creating WOC 2.0 era challenges in large part because these initiatives are placing huge volumes of traffic on the WAN. One such initiative is the migration of virtual machines (VMs) between data centers. During VM migration the machine image, which typically runs 10 Gigabytes or more, the active memory, and the execution state of a virtual machine is transmitted over a WAN from one physical server to another. Another key data center initiative is storage replication. Disk array and filer volumes are expanding rapidly and volume sizes of up to 500 TB 1 PB are becoming increasingly common

4 Virtualized WAN Optimization Controllers WOCs are often referred to as symmetric solutions because they typically require an appliance in both the data center as well as at the branch office or on the end user s device. As detailed in The 2011 Application and Service Delivery Handbook, WOCs implement a wide variety of technologies, including caching, compression, congestion control, forward error correction, protocol acceleration, as well as request prediction and spoofing. As is also explained in The 2011 Application and Delivery Handbook, the phrase virtual appliance gets used in a variety of ways. However, in most cases the phrase virtual appliance refers to the software that provides the appropriate functionality, taken together with its operating system, running in a virtual machine (VM) on top of the hypervisor in a virtualized server or some other similar environment. One of the factors that are driving the deployment of vwocs is the previously mentioned growing interest that IT organizations have in using IaaS solutions and the fact that as discussed in The 2011 Application and Service Delivery Handbook, one of the primary concerns that IT organizations have with using these solutions is performance. SurePrep is an example of a company that a while ago decided to not run a data center of their own and to rely completely on IaaS solutions. Hosek highlighted one of the limitations of a hardware-based WOC when he said that, When we first moved away from having our own data center, our IaaS vendor was not open to installing hardware-based WOCs. IaaS providers typically don t want to install custom hardware for customers. IT organizations can bypass this reluctance by implementing a vwoc at the IaaS provider s site. Another factor that is driving the deployment of vwocs is the proliferation of hypervisors on a variety of types of devices. For example, the majority of IT organizations have virtualized at least some of their data center servers and it is becoming increasingly common to implement disk storage systems that have a storage hypervisor. As a result, in most cases there already are VMs in an enterprise s data center and these VMs can be used to host one or more vwocs. In a branch office, a suitably placed virtualized server could host a vwoc as well as other virtual appliances forming what is sometimes referred to as a Branch Office Box (BOB). Alternatively, a router such as Cisco s ISR G2 that supports router blades could also host a vwoc and function as a BOB. Virtual appliances can therefore support branch office server consolidation strategies by enabling a single device (i.e., server, router) to perform multiple functions typically performed by multiple physical devices. Carrier 2 Carrier provides satellite service to some very remote places. Prior to virtualization, Carrier 2 Carrier would have to have multiple devices at remote sites in order to support voice and video as well as data applications and functionality such as compression and security. Mink stated that installing and powering all of those devices and providing the necessary spares was a logistical nightmare. He added that implementing virtual solutions saves cost and reduces the risk of things going wrong. 4

5 The relative ease of transferring a vwoc has a number of advantages. For example, one of the challenges associated with migrating a VM between physical servers is replicating the VM s networking environment in its new location. However, unlike a hardware-based WOC, a vwoc can be easily migrated along with the VM. This makes it easier for the IT organization to replicate the VMs networking environment in its new location. In addition, many IT organizations choose to implement a proof-of-concept (POC) trial prior to acquiring WOCs. The purpose of these trials is to enable the IT organization to quantify the performance improvements provided by the WOCs and to understand related issues such as the manageability and transparency of the WOCs. While it is possible to conduct a POC using a hardware-based WOC, it is easier to do so with a vwoc. This follows in part because a vwoc can be downloaded in a matter of minutes, whereas it typically takes a few days to ship a hardware-based WOC. Another reason why it is easier to conduct a POC with a vwoc than with a hardware-based WOC is because some vendors allow users to download a vwoc without having any contact with the vendor. In similar fashion, another advantage of a vwoc is that some vendors of vwocs provide a version of their product that is completely free and is obtained on a selfservice basis. Mink stated that when they did a POC, that they got an evaluation license for a vwoc, downloaded and tested it. He concluded that This is absolutely an easier way to do testing. Hosek stated that if he were conducting a POC at a site in the US, that he could easily send people to the site to install the equipment and to do testing but that If I have to get involved in shipping devices internationally it is a big headache. He illustrated the issue by pointing out that SurePrep has a major facility in India and that if he has to ship devices there in order to conduct a POC that there is a lot of bureaucratic overhead and he also has to pay tariffs and taxes. If, at the end of the POC he decides that he doesn t want to keep the equipment, It is a huge bureaucratic nightmare to get your money back and you completely avoid this issue with a virtual appliance. Whether it is for a POC or to implement a production WOC, the difference between the amount of time it takes to download a vwoc and the time it takes to ship a hardware-based appliance is particularly acute if the WOC is being deployed in a part of the world where it can take weeks if not months to get a hardware-based product through customs. For example, Mink pointed out that, If you are doing satellite communications you tend to be in rural locations and the deployment of physical equipment in those locations is expensive, time-consuming and sometimes dangerous. As a result, the less physical equipment you have the better. An interesting side affect of the growing adoption of vwocs is that in many cases community forums have Reasons to use a Virtual WOC (vwoc): Proliferation of hypervisors Ability to accelerate IaaS Mobility - transfer vwoc with other VMs Free vwoc appliances No shipping delays Online community forums Pricing flexibility - pay "as you go" and "as you grow" 5

6 developed around a given vendor s vwoc products. These forums complement and in some cases replace the support that is provided by the vendors of virtual WOCs. When considering vwocs, IT organizations need to realize that there are some significant technical differences in the solutions that are currently available in the marketplace. These differences include the highest speed LAN and WAN links that can be supported as well as which hypervisors are supported; e.g., hypervisors from the leading vendors such as VMware, Citrix and Microsoft as well as proprietary hypervisors from a cloud computing provider such as Amazon. Another key consideration is the ability of the vwoc to fully leverage the multi-core processors being developed by vendors such as Intel and AMD in order to continually scale performance. In addition to technical considerations, IT organizations need to realize that there are some significant differences in terms of how vendors of vwocs structure the pricing of their products. One option provided by some vendors is typically referred to as pay as you go. This pricing option allows IT organizations to avoid the capital costs that are associated with a perpetual license and to acquire and pay for a vwoc on an annual basis. Another option provided by some vendors is typically referred to as pay as you grow. This pricing option provides investment protection because it enables an IT organization to get stared with WAN optimization by implementing vwocs that have relatively small capacity and are priced accordingly. The IT organization can upgrade to a higher-capacity vwoc when needed and only pay the difference between the price of the vwoc that it already has installed and the price of the vwoc that it wants to install. Mink stated that his company utilizes both the pay as you go and pay as you grow pricing models for vwocs. We tend to acquire a vwoc on a yearly basis and we know we can upgrade during the year and just pay the delta. He added that, This approach gives me options. If tomorrow someone says that they need more throughput, I can just turn on a key. If we no longer need the functionality, I can stop it at the end of the year. Hosek commented on the value of being able to scale performance economically when he said that, You definitely want to choose a vendor whose product scales. You need to understand the upgrade path and what it s going to cost you. In addition to technical and pricing concerns, he added that, If you are new to this and you are not getting help from your vendor, you might want to choose another vendor. Summary Virtualization is fundamentally changing the IT function. Part of the way that virtualization is changing IT is that it is creating a new set of performance challenges such as those that are associated with supporting virtual desktops or with enabling the transfer of VMs between physical servers in disparate data centers. Virtualization, however, is also making it easier for IT organizations to respond to a wide range of performance challenges. For example, the proliferation of hypervisors on a variety of devices makes it easier for an IT organization to deploy a virtual appliance such as a vwoc and vwocs provide a number of advantages when compared hardware-based WOCs. vwocs are easier to deploy at an IaaS provider s site and it 6

7 is easier to transfer a vwoc than it is to transfer a hardware-based WOC. The ease of transfer of a vwoc facilitates the dynamic movement of VMs, the ability of an IT organization to conduct a POC for WOCs and the shipping of vwocs to challenging geographies. When considering vwocs, IT organizations need to evaluate a number of technical criteria. This includes the highest speed LAN and WAN links that can be supported as well as which hypervisors are supported. Another key technical consideration is the ability of the vwoc to fully leverage a multi-core processor architecture in order to continually scale performance. In addition to technical criteria, IT organizations should also evaluate the vendor s pricing model. This includes whether or not the vendor offers a pay as you go pricing model that allows IT organizations to avoid the capital costs that are associated with a perpetual license as well as a pay as you grow pricing model that provides the IT organizations with investment protection. 7