PrivateLink: a service exposed as an ENI, nothing more
AWS PrivateLink places an Elastic Network Interface in the consumer's subnet, backed by an NLB in front of the provider's service, so no VPC peering, no route table entries, no public exposure is ever required.
Speaker notes
- AWS PrivateLink works by the provider placing a Network Load Balancer in front of their service and creating a VPC Endpoint Service from it; the consumer then creates an Interface Endpoint (from the earlier VPC endpoints slide) in their own subnet, which provisions an ENI that resolves the service's private DNS name to a private IP inside the consumer's own VPC.
- The security property that matters most: PrivateLink connections are one-directional by design. The consumer can reach the provider's service through the ENI, but the provider's VPC has no route, no visibility, and no reachability into the consumer's VPC at all, a fundamentally tighter isolation boundary than VPC peering, which opens bidirectional routing between two entire address spaces.
- PrivateLink is the right choice specifically when you need strict service-level isolation, when you're exposing a service to an external customer or partner account you don't want any broader network access to, or when the two sides have overlapping CIDR ranges that would make peering impossible outright.
Deck map
01
AWS Networking, end to end
02
The certification landscape: Associate to Professional to Specialty
03
The VPC is the network; everything else attaches to it
04
A subnet lives in exactly one AZ, and that's the whole point
05
The route table decides, the resource doesn't
06
An Internet Gateway makes a subnet public, nothing else does
07
NAT Gateway vs. NAT Instance: managed reliability vs. control
08
Security Groups are stateful, and that's the whole trick
09
Two firewalls, two layers, evaluated in a fixed order
10
Elastic IPs and ENIs: identity that outlives the instance
11
VPC Peering is direct, private, and never transitive
12
Gateway endpoints are free; interface endpoints are PrivateLink
13
ALB, NLB, and Gateway Load Balancer solve different problems
14
Six routing policies, one DNS service
15
CloudFront optimizes what's delivered, not how it travels
16
Shield, WAF, and the edge defense stack
17
VPC Flow Logs: the record of what actually happened
18
Transit Gateway: from N-squared peering to one hub
19
Direct Connect: a physical circuit, not a tunnel
20
Direct Connect resiliency is a model you choose, not a default
21
Direct Connect Gateway: one circuit, many regions
22
Site-to-Site VPN and Client VPN solve different connectivity problems
23
Choosing hybrid connectivity: bandwidth vs. lead time vs. cost
24
Cloud WAN: the network becomes a policy document
25
VPC sharing: one network, many accounts
26
PrivateLink: a service exposed as an ENI, nothing more
27
VPC Lattice moves service networking up to Layer 7
28
PrivateLink vs. VPC Lattice vs. Transit Gateway: the 2026 pattern
29
Route 53 Resolver: DNS that crosses the on-premises boundary
30
Five layers deep: NACL to Shield Advanced
31
Global Accelerator: two static IPs, one fast path
32
Three tools that answer 'why can't this reach that'
33
IPv6 in AWS is additive, not a migration
34
Bandwidth is a design decision, not a given
35
Scenario: a global SaaS platform's hub-and-spoke backbone
36
Scenario: a trading platform's latency and compliance walls
37
Scenario: merging two companies' networks without an outage
38
Scenario: a network that survives losing a region
39
Scenario: exiting a data center without a hard cutover
40
The Advanced Networking Specialty exam, domain by domain
41
The traps that recur across every certification level
42
Quick-fire recall
43
The one-page decision cheat sheet
44
Readiness checklist: is this network actually enterprise-grade?