Welcome!

Linux Containers Authors: Zakia Bouachraoui, Elizabeth White, Yeshim Deniz, Liz McMillan, Pat Romanski

Related Topics: @DevOpsSummit, Microservices Expo, Linux Containers, Containers Expo Blog

@DevOpsSummit: Blog Feed Post

Things Your Proxy Can’t Do | @DevOpsSummit #DevOps #Microservices

Proxies are a bridge between dev and ops and the network

Proxies are one of the more interesting (in my no-doubt biased opinion) “devices” in the network. They’re the basis for caching, load balancing, app security, and even app acceleration services. They’re also a bridge between dev and ops and the network, being commonplace to all three groups and environments in most data center architectures.

But not all proxies are built on the same architectural principles, which means not all proxies are created equal. A large number of proxies are half-proxies while others are full-proxies, and the differences between them are what mean the difference between what you can and cannot do with them. In fact, there are three very important things you can do with a full-proxy that you can’t do with a regular old proxy.

half vs full proxy

Before we jump into those three things, let’s review the differences between them, shall we?

Half-Proxy
Half-proxy is a description of the way in which a proxy, reverse or forward, handles connections. Basically it’s describing the notion that the proxy only mediates connections on the client side. So it only proxies half the communication between the client and the app. The most important thing to recognize about a half-proxy is that it has only one network stack that it shares across both client and server.

Full-Proxy
By contrast, a full-proxy maintains two distinct network stacks – one on the client side, one of the app side – and fully proxies both sides, hence the name. While a full-proxy can be configured to act like a half-proxy, its value is in its typical configuration, which is to maintain discrete connections to both the client and the server.

It is this dual-stack approach that enables a full-proxy to provide capabilities that a half-proxy with its single network stack simply cannot.

The Three Things
A full-proxy completely understands the protocols for which it proxies and is itself both an endpoint and an originator for those protocols and connections. This also means the full-proxy can have its own TCP connection behavior for each network stack such as buffering, retransmits, and TCP options. With a full-proxy each connection is unique; each can have its own TCP connection behavior. This means that a client connecting to the full-proxy device would likely have different connection behavior than the full-proxy  might use for communicating with servers. Full-proxies can look at incoming requests and outbound responses and can manipulate both if the solution allows it.

#1 Optimize client side and server side
Because it can maintain separate network stacks and characteristics, a full-proxy can optimize each side for its unique needs. The TCP options needed to optimize for performance on the client side’s lower-speed, higher-latency network connection – particularly when mobile devices are being served – are almost certainly very different than those needed to optimize for performance on the server side’s high-speed, low latency data center network connection. A full-proxy can optimize both at the same time and thus provide the best performance possible in all situations. A half-proxy, with its single network stack, is forced to optimize for the average of its connections, which certainly means one side or the other is left with less than optimal performance.

#2 Act as a protocol gateway
Protocol gateways are an important tool in the architect’s toolbox particularly when transitioning from one version of an application protocol to another, like HTTP/1 to HTTP/2 or SPDY. Because a full proxy maintains those two unique connections, it can accept HTTP/2 on the client side, for example, but speak HTTP/1 to the server (app). That’s because a full-proxy terminates the client connection (the proxy is the server) and initiatives a different connection to the server (the proxy is the client). The protocol used on the client side doesn’t restrict the choice of protocols on the server side. Realistically, any protocol transition that makes sense (and even those that don’t) can be managed with a full-proxy. A programmable full-proxy ensures that even if its an uncommon (and thus not universally supported) that you can code up a gateway yourself without expending effort on reinventing the proxy-wheel.

#3 Terminate SSL/TLS
Technically this is a specialized case of a protocol gateway but the ascendancy of HTTP/S (and the urgency with which we are encouraged to deploy SSL Everywhere and Encrypt All The Things) makes me treat this as its own case. Basically terminating SSL/TLS is a critical capability in modern and emerging architectures because of the need to inspect and direct HTTP-based traffic (like REST API calls) based on information within the HTTP protocol that would otherwise be invisible thanks to encryption. The ability to terminate SSL/TLS means the proxy becomes the secure endpoint to which clients connect (and ultimately trust). Termination means the proxy is responsible for decrypting requests and encrypting responses and is thus able to “see” into the messages and use the data therein to make routing and load balancing decisions.

So the next time you’re looking at a proxy, don’t forget to find out whether it’s a full proxy or not. Because without a full-proxy, you’re limiting your ability to really take advantage of its capabilities and reaping the benefits it can offer modern and emerging application architectures.

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.

IoT & Smart Cities Stories
René Bostic is the Technical VP of the IBM Cloud Unit in North America. Enjoying her career with IBM during the modern millennial technological era, she is an expert in cloud computing, DevOps and emerging cloud technologies such as Blockchain. Her strengths and core competencies include a proven record of accomplishments in consensus building at all levels to assess, plan, and implement enterprise and cloud computing solutions. René is a member of the Society of Women Engineers (SWE) and a m...
Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settlement products to hedge funds and investment banks. After, he co-founded a revenue cycle management company where he learned about Bitcoin and eventually Ethereal. Andrew's role at ConsenSys Enterprise is a mul...
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
Dynatrace is an application performance management software company with products for the information technology departments and digital business owners of medium and large businesses. Building the Future of Monitoring with Artificial Intelligence. Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more busine...
Nicolas Fierro is CEO of MIMIR Blockchain Solutions. He is a programmer, technologist, and operations dev who has worked with Ethereum and blockchain since 2014. His knowledge in blockchain dates to when he performed dev ops services to the Ethereum Foundation as one the privileged few developers to work with the original core team in Switzerland.
Whenever a new technology hits the high points of hype, everyone starts talking about it like it will solve all their business problems. Blockchain is one of those technologies. According to Gartner's latest report on the hype cycle of emerging technologies, blockchain has just passed the peak of their hype cycle curve. If you read the news articles about it, one would think it has taken over the technology world. No disruptive technology is without its challenges and potential impediments t...
If a machine can invent, does this mean the end of the patent system as we know it? The patent system, both in the US and Europe, allows companies to protect their inventions and helps foster innovation. However, Artificial Intelligence (AI) could be set to disrupt the patent system as we know it. This talk will examine how AI may change the patent landscape in the years to come. Furthermore, ways in which companies can best protect their AI related inventions will be examined from both a US and...
Bill Schmarzo, Tech Chair of "Big Data | Analytics" of upcoming CloudEXPO | DXWorldEXPO New York (November 12-13, 2018, New York City) today announced the outline and schedule of the track. "The track has been designed in experience/degree order," said Schmarzo. "So, that folks who attend the entire track can leave the conference with some of the skills necessary to get their work done when they get back to their offices. It actually ties back to some work that I'm doing at the University of San...
When talking IoT we often focus on the devices, the sensors, the hardware itself. The new smart appliances, the new smart or self-driving cars (which are amalgamations of many ‘things'). When we are looking at the world of IoT, we should take a step back, look at the big picture. What value are these devices providing. IoT is not about the devices, its about the data consumed and generated. The devices are tools, mechanisms, conduits. This paper discusses the considerations when dealing with the...
Bill Schmarzo, author of "Big Data: Understanding How Data Powers Big Business" and "Big Data MBA: Driving Business Strategies with Data Science," is responsible for setting the strategy and defining the Big Data service offerings and capabilities for EMC Global Services Big Data Practice. As the CTO for the Big Data Practice, he is responsible for working with organizations to help them identify where and how to start their big data journeys. He's written several white papers, is an avid blogge...