Why test your new cloud? Ten things you need to know

With the promise of a robust and broad range of next-generation networking offerings, the awareness of cloud computing’s advantages is widely acknowledged. The rich potential benefits of software as a service (SaaS), infrastructure as a service (IaaS) and platform as a service (PaaS), available in combination or individually in scalable data centres or other venues, are well appreciated. The pathway to delivering those advantages in public, private or hybrid clouds, however, require the right level of due diligence to achieve.

Q: We are planning to migrate to a cloud computing solution. My highly qualified IT team has ample experience with designing and implementing new networks. If we have their stamp of approval, is it really necessary to test our newly proposed cloud computing solution any further?

A: The cloud infrastructure - which is a blend of physical and virtual devices, and existing and emerging technologies (some in early stages of adoption) - makes or breaks the cloud service’s quality of experience. What looks good on paper may not be in sync with the ever-evolving complex realities of cloud computing. Findings from Nemertes Research state that launching an IT initiative without testing can completely wipe out the anticipated operational and cost benefits. Testing for performance, availability, security and scale (the cornerstone components of the PASS test methodology) assures the success of a cloud initiative by identifying vulnerabilities that may have been missed in the design and implementation phases. Proper and timely testing before launch assures the delivery on the promises of cloud computing.

Q: Recognising that effective cloud testing needs to address virtual, physical and combined environments, what are some of the specific tests required for effective evaluation of the performance of the cloud?

A: Performance tests from industry standards that address these requirements include: IETF RFC 2544 Network, RFC 2889 LAN Switch, RFC 3918 Multicast, RFC 5180 IPv6 Network and Draft Data Center Bridging Benchmarking.

Q: What exactly is the PASS test methodology?

A: In response to recognising the myriad vulnerabilities stemming from the complex and possibly confounding convergence of processes which constitute the implementation of any cloud computing solution, Spirent Communications developed the industry’s first holistic test methodology to validate the performance, availability, security and scalability (PASS) of cloud computing. These four categories are the cornerstone of success or failure of any IT initiative and have been developed based on top concerns in the industry by IT managers. The Spirent PASS methodology addresses both physical and virtual appliances and is specifically designed to test services and infrastructure between any point in the cloud environment.

Q: What are some of the critical components of testing availability in cloud computing?

A: Cloud IaaS Live Migration is of crucial importance: the movement of IaaS VM instances without the requirement of powering down. Automated resource scheduling, which automatically moves IaaS VM instances at defined load thresholds, is another important component. High availability is also critical in cloud computing, which includes the ability to instantly restart IaaS instances on HW failures. These components require virtualised test environments to produce the depth of metrics required to accurately assess the availability of your solution.

Q: Are adjacent cloud services a serious security threat?

A: Adjacent cloud services can be security threats and these concerns need to be addressed for any cloud solution. Cloud security solutions require traditional security components to work in concert with virtual security elements. You need to test them individually and as a whole, which requires test cases, hardware and virtualised components to assure effective and comprehensive test coverage. Areas where cloud security should be assessed include: user authentication IPSec, SSL VPN, 802.1x, Network Access Control (NAC), RADIUS and network attack/negative traffic testing. Testing of firewalls, IDS/IPS and complex deep packet inspection should also be part of comprehensive security testing.

Q: I’m considering a cloud solution in phases. Does PASS testing take into account my needs for future growth?

A: Scalability and performance testing identifies the breaking points of the system and quantifies the delta between current utilisation levels and maximum, indicating the headroom in the current implementation and deployment. With that information about your real-world headroom, you know to what degree your cloud is future-proofed, and where your subsequent development needs to occur in future phases of your cloud solution growth strategy.

Q: Once quality of experience (QoE) has been assured to cloud customers for SaaS, IaaS and/or the PaaS components, what are the main advantages of the cloud solution from a provider or end-user’s perspective?

A: Cloud provides infinite scalability with opportunity to grow in sync with business requirements and deliver a pay-for-what-you-use model. Some other key advantages are reduced cost, increased storage, highly automated environment, flexibility and mobility. Also it allows IT to shift focus, no longer having to worry about constant server updates and other computing issues.

Q: How critical is it to ensure SLAs in cloud? How will cloud providers be able to provide assurance to the end user?

A: Assuring SLAs in the cloud is critical, especially in a public cloud, as tenants need to be assured of the performance they receive. Continuous testing and monitoring is important, in addition to the predeployment strategies. For this providers will have test equipment integrated in the production network so that it can be used on an as-needed basis.

Q: I recognise the need to test my cloud solution with the PASS methodology. I’ll just have my in-house team take over with these guidelines in mind, right?

A: Best practices clearly indicate testing, before an IT initiative goes live, is an effective practice to mitigate costly risks. However, relying on in-house engineering resources, which may lack the required up-to-date expertise and experience, can produce unreliable test results. The choice of a qualified test partner is critical. Employing a partner with a team of test experts conversant in the challenges of cloud computing, with expertise in the field of data centre testing, is essential. Also, since the cost of the required test equipment can be prohibitive, selecting a partner that also manufactures a broad array of networking test equipment, and provides rental options, offers added advantages.

Q: What specific qualifications do I look for when choosing a test partner?

A: A neutral third party; testing as a core competency; virtual and physical test systems for true end-to-end testing of cloud services; an established global name in the test and measurement industry; experience and expertise; quality test engineers; provides test rental equipment (preferably manufactured by same company); an established delivery process; extensive automation expertise; articulation of testing benefits/ROI vs risk; holistic understanding of networks; successful engagements with references.