Click here to close now.

Welcome!

SDN Journal Authors: AppDynamics Blog, Roger Strukhoff, Liz McMillan, Lori MacVittie, Pat Romanski

Related Topics: SDN Journal, Java, Linux, Virtualization, Cloud Expo, Big Data Journal

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
Chuck Piluso will present a study of cloud adoption trends and the power and flexibility of IBM Power and Pureflex cloud solutions. Speaker Bio: Prior to Data Storage Corporation (DSC), Mr. Piluso founded North American Telecommunication Corporation, a facilities-based Competitive Local Exchange Carrier licensed by the Public Service Commission in 10 states, serving as the company's chairman and president from 1997 to 2000. Between 1990 and 1997, Mr. Piluso served as chairman & founder of ...
SYS-CON Events announced today that Soha will exhibit at SYS-CON's DevOps Summit New York, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Soha delivers enterprise-grade application security, on any device, as agile as the cloud. This turnkey, cloud-based service enables customers to solve secure application access and delivery challenges that traditional or virtualized network solutions cannot solve because they are too expensive, inflexible and operational...
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
of cloud, colocation, managed services and disaster recovery solutions, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. TierPoint, LLC, is a leading national provider of information technology and data center services, including cloud, colocation, disaster recovery and managed IT services, with corporate headquarters in St. Louis, MO. TierPoint was formed through the strategic combination of some of t...
SYS-CON Events announced today that Ciqada will exhibit at SYS-CON's @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Ciqada™ makes it easy to connect your products to the Internet. By integrating key components - hardware, servers, dashboards, and mobile apps - into an easy-to-use, configurable system, your products can quickly and securely join the internet of things. With remote monitoring, control, and alert messaging capability, you will mee...
The best mobile applications are augmented by dedicated servers, the Internet and Cloud services. Mobile developers should focus on one thing: writing the next socially disruptive viral app. Thanks to the cloud, they can focus on the overall solution, not the underlying plumbing. From iOS to Android and Windows, developers can leverage cloud services to create a common cross-platform backend to persist user settings, app data, broadcast notifications, run jobs, etc. This session provide...
SYS-CON Events announced today that Column Technologies, a global technology solutions company, will exhibit at SYS-CON's DevOps Summit 2015 New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. Established in 1998, Column Technologies is a leader in application performance and infrastructure management for commercial and federal markets. The company is headquartered in the United States, with a diverse and talented team of more than 350 employees around th...
SYS-CON Media announced today that @WebRTCSummit Blog, the largest WebRTC resource in the world, has been launched. @WebRTCSummit Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @WebRTCSummit Blog can be bookmarked ▸ Here @WebRTCSummit conference site can be bookmarked ▸ Here
Health care systems across the globe are under enormous strain, as facilities reach capacity and costs continue to rise. M2M and the Internet of Things have the potential to transform the industry through connected health solutions that can make care more efficient while reducing costs. In fact, Vodafone's annual M2M Barometer Report forecasts M2M applications rising to 57 percent in health care and life sciences by 2016. Lively is one of Vodafone's health care partners, whose solutions enable o...
Public Cloud IaaS started it's life in the developer and startup communities and has grown rapidly to a $20B+ industry, but it still pales in comparison to how much is spent worldwide on IT: $3.6 trillion. In fact, there are 8.6 million data centers worldwide, the reality is many small and medium sized business have server closets and colocation footprints filled with servers and storage gear. While on-premise environment virtualization may have peaked at 75%, the Public Cloud has lagged in ado...
Dave will share his insights on how Internet of Things for Enterprises are transforming and making more productive and efficient operations and maintenance (O&M) procedures in the cleantech industry and beyond. Speaker Bio: Dave Landa is chief operating officer of Cybozu Corp (kintone US). Based in the San Francisco Bay Area, Dave has been on the forefront of the Cloud revolution driving strategic business development on the executive teams of multiple leading Software as a Services (SaaS) ap...
The 5th International DevOps Summit, co-located with 17th International Cloud Expo – being held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the...
Database apps on mobile devices shouldn't stop working when there's limited or no network connectivity. In his session at 16th Cloud Expo, Bradley Holt, a Developer Advocate for IBM Cloudant, will discuss how to bring data stored in a cloud database to the edge of the network (and back again), whenever an Internet connection is available. He will demonstrate techniques for replicating cloud databases with mobile devices in order to build offline-enabled mobile apps that can provide a better,...
Modern Systems announced completion of a successful project with its new Rapid Program Modernization (eavRPMa"c) software. The eavRPMa"c technology architecturally transforms legacy applications, enabling faster feature development and reducing time-to-market for critical software updates. Working with Modern Systems, the University of California at Santa Barbara (UCSB) leveraged eavRPMa"c to transform its Student Information System from Software AG's Natural syntax to a modern application lev...
ProfitBricks has launched its new DevOps Central and REST API, along with support for three multi-cloud libraries and a Python SDK. This, combined with its already existing SOAP API and its new RESTful API, moves ProfitBricks into a position to better serve the DevOps community and provide the ability to automate cloud infrastructure in a multi-cloud world. Following this momentum, ProfitBricks has also introduced several libraries that enable developers to use their favorite language to code ...
The IoT Bootcamp is coming to Cloud Expo | @ThingsExpo on June 9-10 at the Javits Center in New York. Instructor. Registration is now available at http://iotbootcamp.sys-con.com/ Instructor Janakiram MSV previously taught the famously successful Multi-Cloud Bootcamp at Cloud Expo | @ThingsExpo in November in Santa Clara. Now he is expanding the focus to Janakiram is the founder and CTO of Get Cloud Ready Consulting, a niche Cloud Migration and Cloud Operations firm that recently got acquir...
The 17th International Cloud Expo has announced that its Call for Papers is open. 17th International Cloud Expo, to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, APM, APIs, Microservices, Security, Big Data, Internet of Things, DevOps and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding bu...
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch ...
The world's leading Cloud event, Cloud Expo has launched Microservices Journal on the SYS-CON.com portal, featuring over 19,000 original articles, news stories, features, and blog entries. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. Microservices Journal offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. Follow new article posts on T...
SYS-CON Events announced today that Litmus Automation will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Litmus Automation’s vision is to provide a solution for companies that are in a rush to embrace the disruptive Internet of Things technology and leverage it for real business challenges. Litmus Automation simplifies the complexity of connected devices applications with Loop, a secure and scalable clou...