Welcome!

Blog Feed Post

Achieving Command and Control through Requests and Responses

I’ve been talking about layer 7 load balancing (L7 LB) since, well, for a long time. From the first inception of it back in the day when someone decided that routing requests using URIs and host headers was a pretty innovative thing to do. bifurcated-network-stateful-statelessIf you must know, that was back in 2001.

And it was innovative then. Because at the time, load balancing and routing was something addressed at layers 3 and 4 – that’s TCP/IP – in the network using routers and switches and load balancers and network architecture.  You didn’t commonly see network devices operating at L7. You just didn’t, except in the app infrastructure.  

Today you see it all the time in the network. That virtual server definition in httpd.conf that relies on HTTP host header? That’s part of L7 LB. Rewriting URLs? Part of L7 LB. Persistent (sticky) sessions? You got this, right? Right. L7 LB.

So basically I’ve spent most of this century preaching about L7 LB.

One Monday morning in May I was reading the Internet (cause I do that on Mondays) and came across a lengthy discussion of microservices and L7 LB.

Guys, I must tell you I was totally excited by this blog. I was excited by the content, by the focus on the role of L7 LB in microservices and emerging app architectures (he mentions canary deployments), and by the words the author used to seamlessly move what has been a traditionally network-focused technology into an ops-focused technology. This is, without a doubt, one of the best (and most concise) descriptions of L7 LB I’ve read on the Internet:

It’s this experience that motivated linkerd (pronounced “linker dee”), a proxy designed to give service operators command & control over traffic between services. This encompasses a variety of features including transport security, load balancing, multiplexing, timeouts, retries, and routing.

In this post, I’ll discuss linkerd’s approach to routing. Classically, routing is one of the problems that is addressed at Layers 3 and 4—TCP/IP—with hardware load balancers, BGP, DNS, iptables, etc. While these tools still have a place in the world, they’re difficult to extend to modern multi-service software systems. Instead of operating on connections and packets, we want to operate on requests and responses. Instead of IP addressees and ports, we want to operate on services and instances.

I highlighted that one part because man, there’s just so much wrapped up in that single statement I can’t even. Literally.

The concept of operating on requests and responses is the foundation of entire solution sets across security, scale, and performance. A proxy capable of inspecting requests and responses is able to note only deal with transport security (TLS/SSL offload) and load balancing, but app security, as well. Request and response inspection is a critical component of app security, scanning and scrubbing of content deep down in the payload (the JSON, the HTML, the XML) to find exploits and malicious content is the premise of a web application firewall.

And then there’s access control, which increasingly cannot simply rely on IP addresses and user names. The proliferation of cloud and roaming, mobile employees and users alike means a greater focus on controlling access to applications based on context. Which means operating on requests and being able to extract a variety of information from it that will provide richer access policies able to cross the chasm from users to things (devices).

And of course there’s scale. Scale today is not about load balancing algorithms, it’s about architecture. Application and operational architecture alike. The use of DevOps-driven deployment patterns like canary and blue-green deployments as well as sharding and partitioning architectures are critical to achieving not just the seamless scale required today but the efficacy of those architectures. L7 LB is key to these endeavors, enabling fine-grained control over the routing of requests and handling of responses between apps (micro or monolith) and users (thing and human). 

And that’s really what the aforementioned (did I mention it was awesome, already?) is talking about: L7 LB. Whether it’s hardware or software, in the cloud or on-premises, isn’t really all that important. That’s an operational detail that is (or should be) irrelevant when we’re talking about architecting a scalable application composed of “services and instances.”

I cannot reiterate often enough the importance of L7 LB as part of modern application architectures. And it’s exciting to see the dev and ops side of the world starting to shout the same thing as they encounter the operational challenges of scale and routing amidst a highly interconnected and interdependent set of services that are the foundation for apps (and business) today.

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.

Latest Stories
Have you ever noticed how some IT people seem to lead successful, rewarding, and satisfying lives and careers, while others struggle? IT author and speaker Don Crawley uncovered the five principles that successful IT people use to build satisfying lives and careers and he shares them in this fast-paced, thought-provoking webinar. You'll learn the importance of striking a balance with technical skills and people skills, challenge your pre-existing ideas about IT customer service, and gain new in...
SYS-CON Events announced today that SD Times | BZ Media has been named “Media Sponsor” of SYS-CON's 20th International Cloud Expo, which will take place on June 6–8, 2017, at the Javits Center in New York City, NY. BZ Media LLC is a high-tech media company that produces technical conferences and expositions, and publishes a magazine, newsletters and websites in the software development, SharePoint, mobile development and commercial UAV markets.
SYS-CON Events announced today that Telecom Reseller has been named “Media Sponsor” of SYS-CON's 20th International Cloud Expo, which will take place on June 6–8, 2017, at the Javits Center in New York City, NY. Telecom Reseller reports on Unified Communications, UCaaS, BPaaS for enterprise and SMBs. They report extensively on both customer premises based solutions such as IP-PBX as well as cloud based and hosted platforms.
SYS-CON Events announced today that Cloudistics, an on-premises cloud computing company, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Cloudistics delivers a complete public cloud experience with composable on-premises infrastructures to medium and large enterprises. Its software-defined technology natively converges network, storage, compute, virtualization, and management into a ...
In his keynote at @ThingsExpo, Chris Matthieu, Director of IoT Engineering at Citrix and co-founder and CTO of Octoblu, focused on building an IoT platform and company. He provided a behind-the-scenes look at Octoblu’s platform, business, and pivots along the way (including the Citrix acquisition of Octoblu).
SYS-CON Events announced today that Juniper Networks (NYSE: JNPR), an industry leader in automated, scalable and secure networks, will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Juniper Networks challenges the status quo with products, solutions and services that transform the economics of networking. The company co-innovates with customers and partners to deliver automated, scalable and secure network...
"I think that everyone recognizes that for IoT to really realize its full potential and value that it is about creating ecosystems and marketplaces and that no single vendor is able to support what is required," explained Esmeralda Swartz, VP, Marketing Enterprise and Cloud at Ericsson, in this SYS-CON.tv interview at @ThingsExpo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Historically, some banking activities such as trading have been relying heavily on analytics and cutting edge algorithmic tools. The coming of age of powerful data analytics solutions combined with the development of intelligent algorithms have created new opportunities for financial institutions. In his session at 20th Cloud Expo, Sebastien Meunier, Head of Digital for North America at Chappuis Halder & Co., will discuss how these tools can be leveraged to develop a lasting competitive advanta...
SYS-CON Events announced today that Loom Systems will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Founded in 2015, Loom Systems delivers an advanced AI solution to predict and prevent problems in the digital business. Loom stands alone in the industry as an AI analysis platform requiring no prior math knowledge from operators, leveraging the existing staff to succeed in the digital era. With offices in S...
SYS-CON Events announced today that Interoute, owner-operator of one of Europe's largest networks and a global cloud services platform, has been named “Bronze Sponsor” of SYS-CON's 20th Cloud Expo, which will take place on June 6-8, 2017 at the Javits Center in New York, New York. Interoute is the owner-operator of one of Europe's largest networks and a global cloud services platform which encompasses 12 data centers, 14 virtual data centers and 31 colocation centers, with connections to 195 add...
SYS-CON Events announced today that HTBase will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. HTBase (Gartner 2016 Cool Vendor) delivers a Composable IT infrastructure solution architected for agility and increased efficiency. It turns compute, storage, and fabric into fluid pools of resources that are easily composed and re-composed to meet each application’s needs. With HTBase, companies can quickly prov...
SYS-CON Events announced today that CA Technologies has been named “Platinum Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY, and the 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business – from apparel to energy – is being rewritten by software. From ...
What if you could build a web application that could support true web-scale traffic without having to ever provision or manage a single server? Sounds magical, and it is! In his session at 20th Cloud Expo, Chris Munns, Senior Developer Advocate for Serverless Applications at Amazon Web Services, will show how to build a serverless website that scales automatically using services like AWS Lambda, Amazon API Gateway, and Amazon S3. We will review several frameworks that can help you build serverle...
SYS-CON Events announced today that SoftLayer, an IBM Company, has been named “Gold Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. SoftLayer, an IBM Company, provides cloud infrastructure as a service from a growing number of data centers and network points of presence around the world. SoftLayer’s customers range from Web startups to global enterprises.
Culture is the most important ingredient of DevOps. The challenge for most organizations is defining and communicating a vision of beneficial DevOps culture for their organizations, and then facilitating the changes needed to achieve that. Often this comes down to an ability to provide true leadership. As a CIO, are your direct reports IT managers or are they IT leaders? The hard truth is that many IT managers have risen through the ranks based on their technical skills, not their leadership abi...