Egress
Definition
Outbound network traffic leaving your cloud environment to the internet or other networks, impacting performance and cost management.
Use Cases
- Netflix: Delivering video streams to end users globally — Netflix uses a content delivery approach (including its Open Connect CDN) to serve video closer to viewers, reducing the amount of traffic that must traverse long-haul networks and optimizing outbound delivery paths. (Lower delivery costs per streamed GB and improved viewer experience through reduced buffering and latency.)
- Cloudflare: Serving cached web content and protecting sites from attacks at the edge — Cloudflare operates a global edge network that caches customer content and serves it from nearby locations, which can reduce the volume of origin-to-internet outbound traffic from a customer’s cloud environment. (Reduced origin egress and improved performance by serving more requests from edge cache rather than the origin infrastructure.)
Provider Equivalents
- AWS: Data Transfer Out (DTO)
- Azure: Bandwidth (Data Transfer)
- GCP: Network egress
- OCI: Outbound Data Transfer
Frequently Asked Questions
- What's the difference between egress and ingress?
- Ingress is inbound traffic coming into your cloud environment (for example, users sending requests to your app). Egress is outbound traffic leaving your cloud environment (for example, your app sending responses back to users or exporting data to another network). Many providers charge more often for egress than ingress.
- When does egress apply in cloud networking?
- Egress applies whenever data leaves your cloud provider’s network boundary. Common cases include sending responses to internet users, downloading objects from cloud storage to on-premises, replicating data to another cloud, or sending logs/metrics to an external SaaS. If traffic stays within the same provider network under specific conditions (for example, within the same region or using private connectivity), it may be cheaper or sometimes not billed as internet egress, depending on the provider and service.
- How much does egress cost?
- Egress cost depends on (1) how many GB/TB you send out, (2) where it goes (public internet vs. same region vs. another region vs. another cloud), (3) the service generating the traffic (compute, load balancer, storage, CDN), and (4) any discounts or committed spend. Providers typically publish per-GB tiers and destination-based rates; using a CDN, caching, compression, private connectivity, or keeping workloads and users in-region can reduce billable egress.
Category: networking
Difficulty: basic
Related Terms
See Also