Latest / The Cloud Business Podcast with Fexingo: AWS, Azure, GCP, and Enterprise Infrastructure / The Hidden Tax of Cloud Virtual IP Addresses
Transcript
- Lucas: Look at the average enterprise cloud bill today and you will see it is no longer just about raw storage or CPU cycles. The real bleed happens in the networking layer, specifically around those invisible assets like virtual IP addresses and the gateways that route traffic through them. Luna: Right, because nobody wakes up excited to pay for an unused IP address, but they do show up on the invoice every month without anyone noticing. Lucas: Exactly. And the issue isn't just the per-hour fee for holding onto an Elastic IP or a static public address. It is the secondary charge for the NAT gateway that sits behind it, which bills by data processed and hourly usage. If that gateway is active but processing very little traffic, you are paying a premium for capacity you never touch. Luna: So we are essentially paying rent on empty office space within our own network architecture. Lucas: That is a perfect way to put it. Let me walk you through a specific case from a mid-sized logistics platform that recently audited their spend. They had deployed a new microservices architecture across three availability zones, but they kept legacy NAT gateways running in two of those zones simply because the original engineers hadn't cleaned up the routing tables after the refactor. Luna: And those gateways were just sitting there, charging by the hour, while all the actual traffic was flowing through the third zone? Lucas: Precisely. The traffic volume in those two dead zones was near zero, yet the fixed hourly cost for the NAT gateways, plus the attached Elastic IP reservations, added up to nearly twelve thousand dollars a month. That is not a typo. It is twelve grand gone into the void because of stale configuration. Luna: Twelve thousand dollars for ghosts in the machine. That has to be one of the most expensive forms of digital hoarding I have heard. Lucas: It gets worse though, because the pricing model encourages this kind of sprawl. When you provision a NAT gateway, the provider makes money whether you use it heavily or not. The marginal cost of adding another gateway is low, so teams tend to over-provision for safety, assuming they might need the headroom later. Luna: But does that headroom actually save you money if you are paying for it regardless of utilization? Or does it just mask the inefficiency until the bill becomes unmanageable? Lucas: It masks the inefficiency entirely. Most finance teams look at the total cloud spend as a black box. They see the big numbers for compute and storage, and they assume the networking overhead is negligible. But when you start scaling out to hundreds of services, those small fixed costs compound rapidly. Luna: So this is really a problem of visibility more than anything else. If the billing dashboard doesn't highlight idle resources clearly, who is going to catch it? Lucas: Usually nobody until it is too late. The logistics company I mentioned didn't even realize the scale of the waste until they hired a dedicated FinOps consultant. She ran a simple query looking for NAT gateways with less than five percent utilization over thirty days. The report came back with eight separate gateways that were effectively doing nothing. Luna: Eight gateways. That sounds like a significant chunk of wasted budget. Did they shut them down immediately? Lucas: They did, but they also had to rethink their entire subnet strategy. You cannot just delete a NAT gateway if other services are still pointing to it. They had to rewrite their DNS records and update security groups to route traffic directly to load balancers instead, bypassing the NAT layer entirely where possible. Luna: Which makes sense because load balancers only charge you for what you process, whereas the NAT gateway charges you for time and volume regardless. Lucas: Correct. The load balancer is a variable cost. The NAT gateway has a heavy fixed component. In high-throughput scenarios, the NAT gateway can actually be cheaper per gigabyte, but in low-throughput or spiky scenarios, it is a terrible deal. The key is matching the tool to the traffic pattern. Luna: So if you have steady, massive traffic, the NAT gateway wins. But if you have sporadic requests or development environments, the load balancer or direct routing is far more efficient. Lucas: You nailed it. And this brings us to a broader point about vendor lock-in. These networking primitives are proprietary to each cloud provider. AWS calls them Elastic IPs and NAT Gateways. Azure has their Public IP addresses and NAT Gateways. GCP has their Cloud NAT. The concepts are similar, but the pricing structures vary wildly. Luna: Which means that optimizing your cloud bill often requires deep knowledge of each provider's specific quirks, rather than just general best practices. Lucas: Absolutely. You cannot apply a one-size-fits-all rule here. For instance, some providers offer free tiers for certain types of internet gateways if you stay under a specific bandwidth threshold. Others charge for every single packet inspection event. It forces your engineering teams to become part-time accountants. Luna: I imagine that friction causes a lot of resentment between engineering and finance. Engineering wants to build fast and use whatever tools make life easiest, while finance just sees the bill growing every month. Lucas: That tension is real. But the solution isn't to restrict engineering access. It is to automate the governance. We are seeing more companies implement policy as code tools that automatically flag or terminate idle resources before they can accumulate significant cost. Luna: Automated cleanup. So if a NAT gateway goes dark for forty-eight hours, the system just kills it and alerts the owner? Lucas: Something like that, though usually with a grace period. Forty-eight hours might be too aggressive for a staging environment that runs intermittently. Maybe seven days is safer. The goal is to catch the obvious waste without breaking legitimate workflows. Luna: Seven days feels reasonable. It gives teams time to notice something is wrong before the resource vanishes, but it stops the bleeding pretty quickly. Lucas: Right. And beyond automation, there is the architectural shift toward serverless networking. Some newer services allow you to handle outbound internet access without provisioning any persistent gateways at all. You pay only for the API calls or the data egress, with no hourly maintenance fee. Luna: That sounds like the ultimate alignment of cost and value. You only pay when you actually move data, not for keeping the lights on in a router. Lucas: Exactly. It removes the incentive to leave things running idly. If there is no hourly fee, there is no penalty for deleting the resource when you aren't using it. It changes the psychological model of how engineers think about infrastructure. Luna: It shifts the focus from uptime to utility. Which is probably a healthier mindset for the long term. Lucas: Definitely. Now, before we dive deeper into how to structure those serverless alternatives, I want to take a brief moment to talk about the show itself. Luna: Yes, let's do that. If these conversations are useful for what you're building or running, consider supporting us directly. Lucas: Listener support is what keeps this podcast ad-free and allows us to keep digging into these niche technical details. You can find us at buy me a coffee dot com slash fexingo. Luna: Any contribution, no matter how small, helps us keep producing this level of analysis for you. Lucas: Thank you for listening. Now, let's get back to that serverless networking question you raised. Luna: Because I am curious if those serverless options are mature enough for production workloads right now, or if they are still mostly experimental. Lucas: They are definitely mature for many use cases. For example, AWS has its VPC Lattice and various managed proxy services that operate on this pay per use model. They handle the complexity of connection pooling and health checks automatically. Luna: So you hand off the operational burden to the provider entirely, and you just deal with the final bill based on throughput. Lucas: That is the promise. However, there is a trade-off. Serverless networking can sometimes introduce slight latency variations compared to a dedicated, always-on hardware gateway. If you are running a real-time trading application, that millisecond difference might matter. Luna: For most businesses though, reliability and cost efficiency outweigh a tiny fraction of a second in latency. Lucas: For ninety-five percent of applications, yes. E-commerce, content delivery, internal dashboards, customer support portals. None of those care about sub-millisecond jitter. They care about predictability and cost control. Luna: So the advice is: audit your current NAT gateways, kill the idle ones, and then evaluate if serverless proxies fit your performance requirements. Lucas: That is a solid roadmap. Start with the easy wins by cleaning up the waste, then move to architectural improvements for the future. It is a two-step process that saves money immediately and sets you up for better scalability later. Luna: I think a lot of CTOs need to hear that message. Stop blaming the cloud providers for high bills and start looking at their own housekeeping. Lucas: Well, the providers are certainly profiting from the complexity, so maybe it is a shared responsibility. But ultimately, the engineer who designed the system is the one who can fix it. Luna: True. And hopefully, by bringing these hidden costs to light, we help those engineers make smarter decisions next time. Lucas: Hopefully. And if you are currently wrestling with a messy VPC setup, I would love to hear how you are handling the transition to cleaner models. Luna: Same here. Let us know what worked for you, and what didn't. Lucas: We will be watching for those stories. Until next time, keep your networks lean and your bills lower. Luna: Thanks for tuning in to The Cloud Business Podcast.