ExpressRoute bills a circuit port fee by bandwidth, in a metered plan (per-GB egress) or unlimited plan (flat, higher fee), plus provider connectivity charges. For large, steady traffic to Azure it can beat VPN. Here is the model.
Private Link bills per private endpoint per hour plus per GB of data processed, keeping traffic to Azure services on the backbone privately. It adds cost but can reduce egress and improve security. Here is the model and the tradeoff.
Cloud Interconnect bills per VLAN attachment (by capacity) plus discounted egress over the connection, in Dedicated (your own 10G/100G ports) or Partner (via a provider) flavors. For large steady traffic it beats VPN. Here is the model.
gRPC's binary encoding and HTTP/2 multiplexing send fewer bytes and use connections more efficiently than JSON over HTTP/1.1, which can cut egress and compute at high volume. But REST is simpler and universal. Here is the cost tradeoff.
AWS (ALB/NLB), Azure (Load Balancer, Application Gateway), and GCP (Cloud Load Balancing) price load balancing on hourly plus capacity/data axes. Layer-4 is cheaper than layer-7. This compares them and the shared choice of layer to your needs.
Cloud Map bills per registered service-discovery resource per month and per API discovery call, plus any health checks. It is inexpensive, but high-frequency discovery lookups from many clients can add up. Here is the model.
App Mesh adds no charge of its own; you pay for the Envoy proxy sidecars that run alongside your services, consuming CPU and memory on every task or pod. At scale, the sidecar overhead is the real cost. Here is what to watch.
Direct Connect bills a port-hour fee by connection speed plus data transfer out at rates well below internet egress. For high, steady traffic to AWS it pays back the port fee; for low volume it does not. Here is the model.
Site-to-Site VPN bills about $0.05 per connection-hour (roughly $36/month) plus standard data transfer out. It is a cheap, quick way to connect on-premises to AWS over the internet. Here is the model and when to prefer Direct Connect.
GCP offers two network service tiers: Premium routes over Google's backbone for best performance, Standard routes over the public internet for cheaper egress. Choosing Standard where performance allows cuts egress cost. Here is the tradeoff.
Since February 2024, AWS charges about $0.005 per hour (roughly $3.60/month) for every public IPv4 address, whether attached or idle. Idle Elastic IPs and sprawling public IPs add up fast. Here is what changed and how to cut it.
Cloud NAT charges an hourly fee plus about $0.045 per GB processed, similar to AWS and Azure NAT. Traffic to Google APIs can skip it with Private Google Access, cutting the data line. Here is how it prices and how to reduce it.
Azure Firewall charges a fixed hourly deployment fee (around $1.25/hour, roughly $900/month) plus about $0.016 per GB processed. The always-on hourly fee, not data processing, is what shocks teams. Here is the breakdown and cheaper alternatives.
Azure Bastion bills a fixed hourly fee by tier (Basic around $0.19/hour, roughly $140/month) plus outbound data transfer. It runs around the clock whether or not anyone connects, so it is worth it for shared access, not one rarely-used VM.
Azure NAT Gateway charges about $0.045 per hour plus about $0.045 per GB processed, the same shape as the AWS NAT gateway. It is often cheaper and simpler than Azure Firewall for outbound-only needs. Here is how it prices and where it fits.
Gateway endpoints for S3 and DynamoDB are free and remove that traffic from your NAT gateway entirely. Interface endpoints cost per hour per AZ plus per GB, which can still beat NAT on high-volume paths. Here is how to choose.
Azure egress is free for the first 100 GB/month, then tiered ~$0.087/GB; ingress is free. Here's the egress map, the patterns that drive the bill, and how a CDN and region co-location cut it.
Global Accelerator is $18/month per accelerator plus a per-GB data-transfer premium. Here's what it's for (anycast IPs, failover, latency), why it's not CloudFront, and how to keep the premium intentional.
Load Balancer (L4) is ~$25-40/month; Application Gateway (L7) starts ~$180/month plus capacity units. Here's what the gap buys, when you need L7, and how to avoid defaulting to the pricier option.
GCP load balancers bill forwarding rules (~$18/month each for the first five) plus data processed. Here's why sprawl drives the bill and how URL maps and a CDN cut it.
VNet peering has no hourly fee but charges ~$0.01/GB each direction (more for global). It bills on both sides. Here's where the cost hides in hub-and-spoke and chatty services, and how to cut it.
Transit Gateway is $0.05/hour per attachment (~$36.50/month each) + $0.02/GB. Here's why it costs more than peering, when the hub is worth it (~4-6 VPCs), and how to cut it.
Azure CDN is pure caching billed per GB egress with no base fee; Front Door adds load balancing and WAF for a monthly base plus requests. Here's which to use and why cache hit ratio drives the bill.
AWS WAF charges $5/month per Web ACL + $1/month per rule + $0.60 per million requests, plus paid add-ons like Bot Control. Here's how the meters stack and how to keep them down.