You’ve probably heard cloudy evangelists telling CIOs how they won’t need the infrastructure engineers once they move their workloads into a public cloud. As always, whatever sounds too good to be true usually is. Compute resources in public clouds still need to be managed, someone still needs to measure application performance, and backups won’t happen by themselves.

Even more important (for networking engineers), network requirements don’t change just because you decided to use someone else’s computers:

• You still need networks and subnets, and to make matters worse most layer-2 tricks like shared IP address or IP address mobility no longer work;
• If you care about high availability, you have to use a plethora of load balancing mechanisms, from internal load balancing to local-, anycast- and DNS-based load balancing;
• You still have to protect your workloads with packet filters (usually called security groups just to confuse you);
• Routing in public clouds is interesting, and works slightly differently in every public cloud;
• You could use web application firewall and DDoS mitigation offered by a public cloud vendor, or bring your own appliances… in which case you’ll have a fun time trying to integrate your network appliances with public cloud routing and forwarding quirks;

I’m told networking engineers configure these aspects of application infrastructure in on-premises deployments because they were made responsible for them and because they know how to make them work and troubleshoot them when needed. Considering that makes the expectations I mentioned at the top of this blog post a bit delusional.

Regardless of all the similarities I mention, there’s a fundamental difference between on-premises and public cloud deployments. While enterprise networking vendors focus on supporting whatever legacy stupidities they find in enterprise networks (hoping to lock their customers into proprietary architectures), public cloud vendors focus on scalability and stability, so their implementations feel and work a bit differently from what you’re used to… but don’t worry, we have you covered. We’ll cover public cloud networking, network security, and hybrid cloud connectivity details in our Networking in Public Cloud Deployments online course… all you need to do is to register before we run out of seats.