# Egress and network paths > Internet transfer, cross-AZ traffic, NAT processing, free allowances, CDN paths, fixed bandwidth, and the per-GB versus port break-even. --- LLMS index: [llms.txt](/llms.txt) --- > [!IMPORTANT] > **Snapshot:** 2026-08-22. Network prices vary by region, path, direction, > tier, and contract. A public transit port is not service-equivalent to cloud > egress; the comparison exposes the different cost curves. ## Direct answer {#answer} Network is its own bill, not an attachment to compute or storage. The same byte can be free on ingress, charged twice across an availability-zone round trip, processed by NAT, and charged again on internet egress. \[ \begin{aligned} \text{network bill} ={}& \sum(\text{bytes} \times \text{path rate}) \\ &+ \text{hourly gateways} + \text{processing} + \text{ports and IPs} \end{aligned} \] Draw the path before applying a rate. ## Current reference paths {#rates} | Provider / service | Path | Snapshot rate | | --- | --- | ---: | | AWS aggregate services | First internet egress allowance | `100 GB/month free` outside China/GovCloud | | AWS aggregate services | Next 10 TB internet egress | `$0.09/GB` (`¥0.610/GB`) | | AWS EC2/RDS | Same-region cross-AZ | commonly `$0.01/GB` each direction | | AWS NAT Gateway | Processing | `$0.045/GB` + `$0.045/hour` reference | | AWS public IPv4 | Address | `$0.005/hour` | | Alibaba ECS Hangzhou | Internet egress by traffic | `¥0.80/GB` | | Alibaba OSS | Busy / off-peak internet egress | `¥0.50 / ¥0.25 per GB` | | Alibaba OSS | CDN origin egress | `¥0.15/GB` | | Alibaba cross-AZ NAT | Processing CU | `¥0.23/GB-equivalent` + `¥0.23/hour` | AWS aggregates egress tiers across many services and regions; eligibility and exceptions matter. Alibaba same-region VPC product communication is often free, but NAT, CEN, EIP, load balancers, cross-region links, and public paths introduce their own meters. ## Fixed bandwidth versus per GB {#port} The self-transit scenario uses a public 1 Gbps line at `¥12,500/month` and a conservative practical load of `100 TB/month`—about 30% of theoretical line rate. This is a procurement anchor, not a universal market price. | Monthly egress | Required 1G ports | Port cost | Effective port ¥/GB | AWS `$0.09` | Alibaba ECS `¥0.8` | Alibaba OSS busy `¥0.5` | | ---: | ---: | ---: | ---: | ---: | ---: | ---: | | 10 TB | 1 | `¥12,500` | `¥1.250` | `¥6,104` | `¥8,000` | `¥5,000` | | 20 TB | 1 | `¥12,500` | `¥0.625` | `¥12,207` | `¥16,000` | `¥10,000` | | 25 TB | 1 | `¥12,500` | `¥0.500` | `¥15,259` | `¥20,000` | `¥12,500` | | 50 TB | 1 | `¥12,500` | `¥0.250` | `¥30,518` | `¥40,000` | `¥25,000` | | 100 TB | 1 | `¥12,500` | `¥0.125` | `¥61,035` | `¥80,000` | `¥50,000` | | 500 TB | 5 | `¥62,500` | `¥0.125` | `¥305,177` | `¥400,000` | `¥250,000` | Break-even volume is: \[ V_{break} = \frac{\text{port monthly price}}{\text{cloud egress price per GB}} \] | Comparison | Material crossing | | --- | ---: | | AWS `$0.09/GB` | `~20.5 TB/month` | | Alibaba ECS `¥0.8/GB` | `~15.6 TB/month` | | Alibaba OSS busy `¥0.5/GB` | `25 TB/month` | The cloud curve starts at zero and scales with bytes. The port curve starts with a fixed step and then has near-zero marginal bytes until the next port. Bursty, uncertain, global, or DDoS-exposed traffic may justify the cloud/CDN premium; stable bulk transfer crosses early. ## Alibaba fixed public bandwidth {#fixed-bandwidth} The public Hangzhou example prices 1 Mbps fixed bandwidth around `¥23/month` versus `¥0.8/GB` by traffic. They cross at `23 / 0.8 = 28.75 GB/month`. One Mbps can theoretically deliver about 328.5 GB/month, so fixed bandwidth becomes cheaper at roughly 8.8% utilization. Peak entitlement and service quality remain different from a by-traffic peak cap. ## Architecture consequences {#architecture} - Use an S3 Gateway Endpoint instead of routing S3 traffic through AWS NAT when applicable. - Avoid accidental cross-AZ round trips for chatty application/database paths. - Price ECS, OSS busy/off-peak, and CDN-origin delivery as separate exits. - Keep stable origin and backup capacity on fixed or private paths; keep global edge, CDN, DDoS, and volatile traffic on statistically pooled services. - Track IPv4, idle NAT, orphan load balancers, and cross-region replication as first-class meters. ## Exit capability {#exit} Provider exit waivers can materially change C1, but only when eligibility, covered services, destination, notice, transfer window, and approval process are documented. A negotiated or conditional waiver is recorded separately from the default meter. The operational export path and time limit remain part of the test even when the rate is zero. ## Historical insight {#history} AWS marginal egress fell from `$0.20/GB` in 2006 to `$0.09` in 2014, then remained flat through the snapshot. Alibaba ECS Hangzhou stayed at `¥0.8/GB` across the report's 2016–2026 anchors. Silicon and disk gains do not automatically flow into the network meter. See [Cloud price history](/ledger/price-history/). ## Boundaries {#boundaries} - Port procurement lacks the cloud platform's global backbone, elasticity, routing, DDoS, operations, and zero-startup option. - The 1 Gbps quote and 100 TB practical load are scenario inputs. - Taxes, installation, private contracts, and regional fees can move crossings. - All rates must be refreshed after the snapshot before procurement. ## Data and sources {#data} - [Cloud transfer rates](/data/cloud-pricing/2026-08-22-v1/tables/traffic_rates.csv) - [Egress scale curve](/data/build-vs-buy/2026-08-24-v1/tables/egress_scale_curve.csv) - [Pricing source ledger](/data/cloud-pricing/2026-08-22-v1/tables/source_ledger.csv) - [Build-versus-buy source ledger](/data/build-vs-buy/2026-08-24-v1/tables/source_ledger.csv)