Welcome!

SDN Journal Authors: Liz McMillan, Stefan Bernbo, Michel Courtoy, Amitabh Sinha, Mike Wood

Related Topics: SDN Journal, Java IoT, Linux Containers, Containers Expo Blog, @CloudExpo, @BigDataExpo

SDN Journal: Blog Feed Post

What a Network Engineer Does

Network Engineering workflow can be characterized by overlapping cycles of Activity and Modeling

In a previous article, we talked about “Short T’s.”  We talked about how, in network engineering, the “T” is very long:  Configuring a network to achieve business goals requires considerable skill and knowledge.  While we set up a conceptual model in that post to talk about what “T” means in general terms, we did not discuss in detail how to articulate “T” more specifically for network engineering.  In this post, we’ll explore this in a little more detail.

The NetEng Cycle

Figure 1: The Network Engineering Cycle

Network Engineering workflow can be characterized by overlapping cycles of Activity and Modeling.  In figure 1, I have depicted 4 cycles.  From smallest timescale to largest, these are called:  1. Referential Traversal, 2. Interactive, 3. Design, and 4. Architecture.  The crest of each of these cycles is “Activity” and the trough is “Modeling.”  Modeling on the smaller cycles is simple and correlative, while on the larger cycles it is more abstract and analytical.  Activity on the smaller cycles is characterized by direct interactivity with the network, while on larger scales it is indirect and more design oriented.

As is implied from the diagram, a network engineer will oscillate between activities and modeling.  For instance, in the interactive cycle, they may configure a QoS classification policy, but then immediately issue show commands to see if traffic is being classified appropriately.  Configuring a policy and issuing of show commands are activities, but the show commands start to transition into modeling.  The engineer is attempting to model the immediate effect of the changes they have made.  Based on this modeling of “how things are,” the engineer might start thinking about modifications to the classification policy to bring the operation of the network closer to an expected model of “how things should be.”  As far as it is possible to do so, an attempt might be made to model “how things will be” to check for possible side effects.  The cycle, then, repeats.

Referential Space
However, which show commands should they use to accurately model how the configuration is actually working?  If you were to write down the exact sequence of commands, you might find that the engineer is taking data from the output of the first command and using that as either input into the second command, or as a point of reference while examining output from the second command.  The output from the second command might be, in turn, used similarly when executing a third show command.  This is what is called Referential Traversal.  Referential Traversal is when a network engineer engages in iterative data correlation in support of a workflow.  In the context of a workflow, this data represents that workflow’s state.

Another well known referential traversal is doing a manual packet-walk of the network:  Examining nodes along the way to determine if there is a potential issue along the path between two endpoints on the edge of the network.  Here, the engineer will examine lookup tables, arp entries, and LLDP neighbor information, jumping from one node to the next.  This particular workflow can tangent in tricky ways such as examining when and what configuration changes were made to see if they could impact traffic between those two endpoints.  When tangenting into examination of a device configuration, you enter a different set of correlated data:  A route-map applied to an interface can, in turn, reference access-lists or prefix-lists.  The rules for evaluating packet flow through a policy follows different logic than the general rules for packet flow across a series of devices.

Figure 2: Referential Space

Figure 2: Referential Space

If you take the set of rules, relationships, and data points from “configuration space” and the rules, relationships, and data points from the “forwarding space,” and you combine them with all other such spaces that a network engineer must deal with in the course of their activities, the sum of these is called “referential space” (See Figure 2).  A network engineering workflow will follow some referential path through this space, examining data and following it’s relationships to yet other data.  There are numerous interconnected spaces in the management, control, forwarding, and device planes of a network each with their own logic and types of data. There are more abstract spaces as well, such as a “design” space that contains the rules and relationships that govern network design.  A network engineer’s expertise is measured by how well they can navigate referential space in support of longer time-scale cycles.

Enablement versus Obviation
The challenge of networking, and the reason that automation (and UX/UI for that matter) has not evolved terribly well, is that these referential paths vary greatly based on what the network engineer is trying to do and how a particular network is built.  There is a vast set of rules governing the many relationships that exist between the seemingly infinite array of data types.  The dynamic nature of referential traversal, and the intimidating size of referential space, should justify a healthy skepticism of vendors claiming to encapsulate network complexity or automate network workflows.  More often than not, they are simply moving the complexity around, while making it more difficult to navigate in the process.

It’s long since overdue to move innovation in networking towards enabling network engineers to be more effective instead of trying to obviate them.  Unlike the past, this should happen with a keen understanding of what network engineers actually do and how they think through their activities.  We can augment these activities to reduce time-to-completion, and reduce time-to-insight while at the same reducing risk and increasing accountability.  There are many networking workflows, which after 20 years, are still notoriously difficult and risky to model and complete.  Let’s solve these problems first.

Make Things Better
As a network engineer, how many times have you heard about the glorious wonders of a product that automates networking or encapsulates network complexity in some way?  After 20 years, we have been trained to identify this language as snake-oil, or perhaps a little nicer, “marketing speak.”  When we buy into these products or features, it’s always just a matter of time before they go unused, or the ugly realities of their operation surfaces.

Encapsulating network complexity, or automating network workflows, can’t just be about “faster.”  That’s only part of the problem.  It has to make things “better.”  This can only happen with a deeper understanding of referential space.

The post What a Network Engineer Does appeared first on Plexxi.

Read the original blog entry...

More Stories By Derick Winkworth

Derick Winkworth has been a developer, network engineer, and IT architect in various verticals throughout his career.He is currently a Product Manager at Plexxi, Inc where he focuses on workflow automation and product UX.

@CloudExpo Stories
Blockchain is a shared, secure record of exchange that establishes trust, accountability and transparency across business networks. Supported by the Linux Foundation's open source, open-standards based Hyperledger Project, Blockchain has the potential to improve regulatory compliance, reduce cost as well as advance trade. Are you curious about how Blockchain is built for business? In her session at 21st Cloud Expo, René Bostic, Technical VP of the IBM Cloud Unit in North America, will discuss th...
While some vendors scramble to create and sell you a fancy solution for monitoring your spanking new Amazon Lambdas, hear how you can do it on the cheap using just built-in Java APIs yourself. By exploiting a little-known fact that Lambdas aren’t exactly single-threaded, you can effectively identify hot spots in your serverless code. In his session at @DevOpsSummit at 21st Cloud Expo, Dave Martin, Product owner at CA Technologies, will give a live demonstration and code walkthrough, showing how ...
SYS-CON Events announced today that CA Technologies has been named “Platinum Sponsor” of SYS-CON's 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 planning to development to management to security, CA creates software that fuels transformation for companies in the applic...
Cloud adoption is often driven by a desire to increase efficiency, boost agility and save money. All too often, however, the reality involves unpredictable cost spikes and lack of oversight due to resource limitations. In his session at 20th Cloud Expo, Joe Kinsella, CTO and Founder of CloudHealth Technologies, tackled the question: “How do you build a fully optimized cloud?” He will examine: Why TCO is critical to achieving cloud success – and why attendees should be thinking holistically ab...
Internet of @ThingsExpo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devic...
As more and more companies are making the shift from on-premises to public cloud, the standard approach to DevOps is evolving. From encryption, compliance and regulations like GDPR, security in the cloud has become a hot topic. Many DevOps-focused companies have hired dedicated staff to fulfill these requirements, often creating further siloes, complexity and cost. This session aims to highlight existing DevOps cultural approaches, tooling and how security can be wrapped in every facet of the bu...
WebRTC is great technology to build your own communication tools. It will be even more exciting experience it with advanced devices, such as a 360 Camera, 360 microphone, and a depth sensor camera. In his session at @ThingsExpo, Masashi Ganeko, a manager at INFOCOM Corporation, will introduce two experimental projects from his team and what they learned from them. "Shotoku Tamago" uses the robot audition software HARK to track speakers in 360 video of a remote party. "Virtual Teleport" uses a...
yperConvergence came to market with the objective of being simple, flexible and to help drive down operating expenses. It reduced the footprint by bundling the compute/storage/network into one box. This brought a new set of challenges as the HyperConverged vendors are very focused on their own proprietary building blocks. If you want to scale in a certain way, let’s say you identified a need for more storage and want to add a device that is not sold by the HyperConverged vendor, forget about it....
SYS-CON Events announced today that Calligo has been named “Bronze Sponsor” of SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Calligo is an innovative cloud service provider offering mid-sized companies the highest levels of data privacy. Calligo offers unparalleled application performance guarantees, commercial flexibility and a personalized support service from its globally located cloud platform...
SYS-CON Events announced today that Elastifile will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Elastifile Cloud File System (ECFS) is software-defined data infrastructure designed for seamless and efficient management of dynamic workloads across heterogeneous environments. Elastifile provides the architecture needed to optimize your hybrid cloud environment, by facilitating efficient...
As DevOps methodologies expand their reach across the enterprise, organizations face the daunting challenge of adapting related cloud strategies to ensure optimal alignment, from managing complexity to ensuring proper governance. How can culture, automation, legacy apps and even budget be reexamined to enable this ongoing shift within the modern software factory?
SYS-CON Events announced today that Cloudistics, an on-premises cloud computing company, has been named “Bronze Sponsor” of SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Launched in 2016, Cloudistics helps anyone bring the power of the cloud to the data center in an easy-to-use, on- premises cloud platform that automatically provides high performance resources for all types of applications: Docke...
With Cloud Foundry you can easily deploy and use apps utilizing websocket technology, but not everybody realizes that scaling them out is not that trivial. In his session at 21st Cloud Expo, Roman Swoszowski, CTO and VP, Cloud Foundry Services, at Grape Up, will show you an example of how to deal with this issue. He will demonstrate a cloud-native Spring Boot app running in Cloud Foundry and communicating with clients over websocket protocol that can be easily scaled horizontally and coordinate...
SYS-CON Events announced today that Golden Gate University will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Since 1901, non-profit Golden Gate University (GGU) has been helping adults achieve their professional goals by providing high quality, practice-based undergraduate and graduate educational programs in law, taxation, business and related professions. Many of its courses are taug...
@DevOpsSummit at Cloud Expo taking place Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center, Santa Clara, CA, is co-located with the 21st International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is ...
SYS-CON Events announced today that Golden Gate University will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Since 1901, non-profit Golden Gate University (GGU) has been helping adults achieve their professional goals by providing high quality, practice-based undergraduate and graduate educational programs in law, taxation, business and related professions. Many of its courses are taug...
DevOps at Cloud Expo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to w...
SYS-CON Events announced today that Secure Channels, a cybersecurity firm, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Secure Channels, Inc. offers several products and solutions to its many clients, helping them protect critical data from being compromised and access to computer networks from the unauthorized. The company develops comprehensive data encryption security strategie...
Recently, WebRTC has a lot of eyes from market. The use cases of WebRTC are expanding - video chat, online education, online health care etc. Not only for human-to-human communication, but also IoT use cases such as machine to human use cases can be seen recently. One of the typical use-case is remote camera monitoring. With WebRTC, people can have interoperability and flexibility for deploying monitoring service. However, the benefit of WebRTC for IoT is not only its convenience and interopera...
Vulnerability management is vital for large companies that need to secure containers across thousands of hosts, but many struggle to understand how exposed they are when they discover a new high security vulnerability. In his session at 21st Cloud Expo, John Morello, CTO of Twistlock, will address this pressing concern by introducing the concept of the “Vulnerability Risk Tree API,” which brings all the data together in a simple REST endpoint, allowing companies to easily grasp the severity of t...