Welcome!

AJAX & REA Authors: RealWire News Distribution, Harald Zeitlhofer

Related Topics: SDN Journal, SOA & WOA, Virtualization, Cloud Expo, Security, Big Data Journal

SDN Journal: Blog Feed Post

Service Chaining and Unintended Consequences

Service chaining in a nutshell is basically orchestration of network services

Service chaining is a popular term today to describe a process in the network that's been done in the land of application integration for a long time. Service chaining in a nutshell is basically orchestration of network services. This concept is being put forth as the way future data center networks will be designed and execute in the future.

Its unintended consequence is, of course, that chaining can have a profound impact on performance, particularly when (or if) those chains extend across providers.

Let's consider an existing service chaining example that's challenging for SSL in terms of performance.

The Rest of the "SSL Performance" Story

Now, we're all aware that SSL handshaking introduces latency. It has to because in addition to the already time-consuming process of performing cryptographic functions, it requires additional round trips between the client (browser) and server (or intermediate network proxy acting as the endpoint, such as a load balancer or ADC) to exchange the information needed to encrypt and decrypt subsequent communication.

But that's not all it needs to do. The certificate offered up by the server-side device is increasingly suspect thanks to a variety of incidents in which basically forged certificates were used to impersonate a site and trick the user into believing the site was safe. As the SSL Everywhere movement continues to grow, so has the decision by browsers to properly validate certificates by querying an OCSP (Online Certificate Status Protocol) responder as to the status of the certificate (this is increasingly favored over the use of CRL (Certificate Revocation Lists) to address certain shortcomings of the technology).

What this means is that during the SSL handshake, the client makes a request to an OCSP responder. It's an additional service in the connection chain that adds time to the "load" process. Thus, it needs to be as fast as possible because it's counted in the "load time" for a page, if not technically then from the perspective of the user which, as we all know, is what really counts.

So the browser makes a request to the responder. It does this by choosing a responder from a list of those that support the CA (Certificate Authority, the issuer of the certificate in question). While there are a large number of global CAs, the actual number of global CAs for SSL is fairly small. Thus the responder is almost certainly very large and likely to see billions of requests a day, from around the globe. This "link in the chain" is increasingly important to the overall performance experienced by the end-user. Its impact on mobile users, in particular, is worthy of note given the impact of mobile networks and constrained device capabilities, as noted by Mike Belshe, one of the folks who helped create the SPDY protocol (emphasis mine):

But this process is pretty costly, especially on mobile networks. For my own service, I just did a quick trace over 3G:

  • DNS (1334ms)
  • TCP handshake (240ms)
  • SSL handshake (376ms)
  • Follow certificate chain (1011ms) — server should have bundled this.
  • DNS to CA (300ms)
  • TCP to CA (407ms)
  • OCSP to CA #1 (598ms) — StartSSL CA uses connection close on each!
  • TCP to CA #2 (317ms)
  • OCSP to CA #2 (444ms)
  • Finish SSL handshake (1270ms)

-- Rethinking SSL for Mobile Apps

The emphasized portions of the transaction indicate those related to the certificate verification process being carried out by the browser as a security precaution. Over a non-mobile network, one would expect the performance to improve, but the impact on "regular" browsers should not be underestimated, either. Early last year Adam Langley noted this and proposed to disable OSCP validation in Chrome: .

The median time for a successful OCSP check is ~300ms and the mean is nearly a second. This delays page loading and discourages sites from using HTTPS. They are also a privacy concern because the CA learns the IP address of users and which sites they're visiting.

On this basis, we're currently planning on disabling online revocation checks in a future version of Chrome.

http://www.imperialviolet.org/2012/02/05/crlsets.html

I'll save the security-related arguments for another time, but suffice to say that the impact of service chaining on performance in the case of SSL and certificate validation is significant enough at times to be noticed.

Key Takeaway

Now certainly service chaining in other contexts, say in the data center network, would not experience the same magnitude of delay based purely on the fact that we're talking about LAN speeds rather than what often end up being inter- or cross-continental communications. Still, the very real impact of service chaining, particularly when such chains are comprised of a long string of services, should not be ignored or underestimated. Such chains introduce  additional latency, often in the form of unnecessary, duplicated functions as well as the possibility of failure. Load and utilization monitoring and scaling strategies of individual (dependent) services is a vital to the overall success of any architecture which employs an orchestrated (chained) services strategy.

And while technologies like SDN and cloud offer corrective action in the face of failure, it should be noted that such corrections tend to be reactions to failure. That means at least one user experiences a failure before a correction is made. In some cases that failure will go unnoticed except for a lengthier response time, but the key takeaway there is that it is noticeable.

And when it comes to web application performance, noticeable degradations are not something the business or operations, for that matter, likes to see. Not even for a single user.

Read the original blog entry...

More Stories By Lori MacVittie

Lori MacVittie is responsible for education and evangelism of application services available across F5’s entire product suite. Her role includes authorship of technical materials and participation in a number of community-based forums and industry standards organizations, among other efforts. MacVittie has extensive programming experience as an application architect, as well as network and systems development and administration expertise. Prior to joining F5, MacVittie was an award-winning Senior Technology Editor at Network Computing Magazine, where she conducted product research and evaluation focused on integration with application and network architectures, and authored articles on a variety of topics aimed at IT professionals. Her most recent area of focus included SOA-related products and architectures. She holds a B.S. in Information and Computing Science from the University of Wisconsin at Green Bay, and an M.S. in Computer Science from Nova Southeastern University.

Cloud Expo Latest Stories
14th International Cloud Expo, held on June 10–12, 2014 at the Javits Center in New York City, featured three content-packed days with a rich array of sessions about the business and technical value of cloud computing, Internet of Things, Big Data, and DevOps led by exceptional speakers from every sector of the IT ecosystem. The Cloud Expo series is the fastest-growing Enterprise IT event in the past 10 years, devoted to every aspect of delivering massively scalable enterprise IT as a service.
As more applications and services move "to the cloud" (public or on-premise) cloud environments are increasingly adopting and building out traditional enterprise features. This in turn is enabling and encouraging cloud adoption from enterprise users. In many ways the definition is blurring as features like continuous operation, geo-distribution or on-demand capacity become the norm. NuoDB is involved in both building enterprise software and using enterprise cloud capabilities. In his session at 15th Cloud Expo, Seth Proctor, CTO at NuoDB, Inc., will discuss the experiences from building, deploying and using enterprise services and suggest some ways to approach moving enterprise applications into a cloud model.
Until recently, many organizations required specialized departments to perform mapping and geospatial analysis, and they used Esri on-premise solutions for that work. In his session at 15th Cloud Expo, Dave Peters, author of the Esri Press book Building a GIS, System Architecture Design Strategies for Managers, will discuss how Esri has successfully included the cloud as a fully integrated SaaS expansion of the ArcGIS mapping platform. Organizations that have incorporated Esri cloud-based applications and content within their business models are reaping huge benefits by directly leveraging cloud-based mapping and analysis capabilities within their existing enterprise investments. The ArcGIS mapping platform includes cloud-based content management and information resources to more widely, efficiently, and affordably deliver real-time actionable information and analysis capabilities to your organization.
In his session at 15th Cloud Expo, Mark Hinkle, Senior Director, Open Source Solutions at Citrix Systems Inc., will provide overview of the open source software that can be used to deploy and manage a cloud computing environment. He will include information on storage, networking(e.g., OpenDaylight) and compute virtualization (Xen, KVM, LXC) and the orchestration(Apache CloudStack, OpenStack) of the three to build their own cloud services. Speaker Bio: Mark Hinkle is the Senior Director, Open Source Solutions, at Citrix Systems Inc. He joined Citrix as a result of their July 2011 acquisition of Cloud.com where he was their Vice President of Community. He is currently responsible for Citrix open source efforts around the open source cloud computing platform, Apache CloudStack and the Xen Hypervisor. Previously he was the VP of Community at Zenoss Inc., a producer of the open source application, server, and network management software, where he grew the Zenoss Core project to over 10...
Almost everyone sees the potential of Internet of Things but how can businesses truly unlock that potential. The key will be in the ability to discover business insight in the midst of an ocean of Big Data generated from billions of embedded devices via Systems of Discover. Businesses will also need to ensure that they can sustain that insight by leveraging the cloud for global reach, scale and elasticity. In his session at Internet of @ThingsExpo, Mac Devine, Distinguished Engineer at IBM, will discuss bringing these three elements together via Systems of Discover.
Cloud and Big Data present unique dilemmas: embracing the benefits of these new technologies while maintaining the security of your organization’s assets. When an outside party owns, controls and manages your infrastructure and computational resources, how can you be assured that sensitive data remains private and secure? How do you best protect data in mixed use cloud and big data infrastructure sets? Can you still satisfy the full range of reporting, compliance and regulatory requirements? In his session at 15th Cloud Expo, Derek Tumulak, Vice President of Product Management at Vormetric, will discuss how to address data security in cloud and Big Data environments so that your organization isn’t next week’s data breach headline.
The cloud is everywhere and growing, and with it SaaS has become an accepted means for software delivery. SaaS is more than just a technology, it is a thriving business model estimated to be worth around $53 billion dollars by 2015, according to IDC. The question is – how do you build and scale a profitable SaaS business model? In his session at 15th Cloud Expo, Jason Cumberland, Vice President, SaaS Solutions at Dimension Data, will give the audience an understanding of common mistakes businesses make when transitioning to SaaS; how to avoid them; and how to build a profitable and scalable SaaS business.
SYS-CON Events announced today that Gridstore™, the leader in software-defined storage (SDS) purpose-built for Windows Servers and Hyper-V, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Gridstore™ is the leader in software-defined storage purpose built for virtualization that is designed to accelerate applications in virtualized environments. Using its patented Server-Side Virtual Controller™ Technology (SVCT) to eliminate the I/O blender effect and accelerate applications Gridstore delivers vmOptimized™ Storage that self-optimizes to each application or VM across both virtual and physical environments. Leveraging a grid architecture, Gridstore delivers the first end-to-end storage QoS to ensure the most important App or VM performance is never compromised. The storage grid, that uses Gridstore’s performance optimized nodes or capacity optimized nodes, starts with as few a...
SYS-CON Events announced today that Solgenia, the global market leader in Cloud Collaboration and Cloud Infrastructure software solutions, will exhibit at SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Solgenia is the global market leader in Cloud Collaboration and Cloud Infrastructure software solutions. Designed to “Bridge the Gap” between personal and professional social, mobile and cloud user experiences, our solutions help large and medium-sized organizations dramatically improve productivity, reduce collaboration costs, and increase the overall enterprise value by bringing collaboration and infrastructure solutions to the cloud.
Cloud computing started a technology revolution; now DevOps is driving that revolution forward. By enabling new approaches to service delivery, cloud and DevOps together are delivering even greater speed, agility, and efficiency. No wonder leading innovators are adopting DevOps and cloud together! In his session at DevOps Summit, Andi Mann, Vice President of Strategic Solutions at CA Technologies, will explore the synergies in these two approaches, with practical tips, techniques, research data, war stories, case studies, and recommendations.
Enterprises require the performance, agility and on-demand access of the public cloud, and the management, security and compatibility of the private cloud. The solution? In his session at 15th Cloud Expo, Simone Brunozzi, VP and Chief Technologist(global role) for VMware, will explore how to unlock the power of the hybrid cloud and the steps to get there. He'll discuss the challenges that conventional approaches to both public and private cloud computing, and outline the tough decisions that must be made to accelerate the journey to the hybrid cloud. As part of the transition, an Infrastructure-as-a-Service model will enable enterprise IT to build services beyond their data center while owning what gets moved, when to move it, and for how long. IT can then move forward on what matters most to the organization that it supports – availability, agility and efficiency.
Every healthy ecosystem is diverse. This is especially true in cloud ecosystems, where portability and interoperability are more important than old enterprise models of proprietary ownership. In his session at 15th Cloud Expo, Mark Baker, Server Product Manager at Canonical/Ubuntu, will discuss how single vendors used to take the lead in creating and delivering technology, but in a cloud economy, where users want tools of their preference, when and where they need them, it makes no sense.
The 15th International Cloud Expo has just expanded its conference program, to bring together Cloud Computing, APM, APIs, Security, Big Data, Internet of Things, DevOps and WebRTC at one location. Cloud Expo is the single show where delegates and technology vendors can meet to experience and discuss the entire world of the cloud. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to learn about the latest technology developments and solutions.
SYS-CON Events announced today that Bsquare Corporation, a leading enabler of smart connected systems, has been named “Bronze Sponsor” of SYS-CON's Internet of @ThingsExpo, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Bsquare is a global leader of embedded software solutions. We enable smart connected systems at the device level and beyond that millions use every day and provide actionable data solutions for the growing Internet of Things (IoT) market. We empower our world-class customers with our products, services and solutions to achieve innovation and success.
SYS-CON Events announced today that NuoDB, Inc., the leader in webscale distributed database technology, has been named “Bronze Sponsor” of SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. NuoDB was launched in 2010 by industry-renowned database architect Jim Starkey and accomplished software CEO Barry Morris to deliver a webscale distributed database management system that is specifically designed for the cloud and the modern datacenter.