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Terry Slattery

Wake Up to Containers

Will containers replace VMs in the near future? How would that impact networking?


Containers are lightweight application instances that run in servers without the need for a full VM. To get an idea of what containers are, see the Wikipedia article on Docker, which is one type of container system. A library and kernel functions provide the abstractions needed for storage, network access, security, etc.

Why should networking people care? Well, it means that applications will be able to be provisioned and functional much faster than if they had to wait for a full OS to be installed and booted. We’re talking about times under a minute, with an eventual goal of having fully operational applications within seconds of deciding that it is needed. That’s fast enough to respond to rapid changes in compute demand.

The Impact on Networking

Maybe it still isn’t clear how this is important to networking. The network will need to be provisioned within that same timeframe. That’s way faster than even what has been discussed with regard to configuring the network to support new VMs and VM migration. There’s no way that humans can be in the middle of this process. It is happening in a big way across all the big infrastructure providers, as described in this Network World article.

OK, so it will probably not impact most enterprise customers for a while yet. But one thing is for certain: It is coming to enterprises in the next few years (3-5?). As equipment refresh times come up, enterprises will have a choice on what technology upgrades to implement. Those enterprises that are the most agile will have an edge over those who don’t adapt. Think of it as evolution in the business world. The agile and adaptable will survive best.

Networking must embrace automation in a big way. This is going to be a shock to a lot of people. It will take a while to happen, primarily due to the rollout of the necessary systems, both hardware and in terms of policies, processes, procedures, and staff education.

What can we networking people do? We’ll have to give up on the old processes we followed that involved manual network configuration. Most of the networking people I know don’t like to use automation. They know that it can break a network very quickly if it tries to implement something that’s not right. Many network staff members didn’t want to use a tool that could propagate a bad configuration change faster than they could manually go behind and fix it. Well, those days are numbered.

Read, learn, and start adapting. Automation is on its way.

Terry Slattery

Terry Slattery

Principal Architect

Terry Slattery is a Principal Architect at NetCraftsmen, an advanced network consulting firm that specializes in high-profile and challenging network consulting jobs. Terry is currently working on network management, SDN, business strategy consulting, and interesting legal cases. He is the founder of Netcordia, inventor of NetMRI, has been a successful technology innovator in networking during the past 20 years, and is co-inventor on two patents. He has a long history of network consulting and design work, including some of the first Cisco consulting and training. As a consultant to Cisco, he led the development of the current Cisco IOS command line interface. Prior to Netcordia, Terry founded Chesapeake Computer Consultants, which became a Cisco premier training and consulting partner. At Chesapeake, he co-invented and patented the v-LAB system to provide hands-on access to real hardware for the hands-on component of internetwork training classes. Terry co-authored the successful McGraw-Hill text "Advanced IP Routing in Cisco Networks," is the second CCIE (1026) awarded, and is a regular speaker at Enterprise Connect and Interop. He currently blogs at TechTarget, No Jitter and our very own NetCraftsmen.

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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

CCIE #1066, CCDE #20070002, CCAr
Chief Technology Officer, Practice Lead Security Services, NetCraftsmen

John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.