AWS VPN connections are used to extend on-premises data centers to AWS.
VPN connections provide secure IPSec connections between the data center or branch office and the AWS resources.
AWS Site-to-Site VPN or AWS Hardware VPN or AWS Managed VPN
Connectivity can be established by creating an IPSec, hardware VPN connection between the VPC and the remote network.
On the AWS side of the VPN connection, a Virtual Private Gateway (VGW) or Transit Gateway provides two VPN endpoints for automatic failover.
On the customer side, a customer gateway (CGW) needs to be configured, which is the physical device or software application on the remote side of the VPN connection
AWS Client VPN is a managed client-based VPN service that enables secure access to AWS resources and resources in the on-premises network.
AWS VPN CloudHub
For more than one remote network e.g. multiple branch offices, multiple AWS hardware VPN connections can be created via the VPC to enable communication between these networks
AWS Software VPN
A VPN connection can be created to the remote network by using an EC2 instance in the VPC that’s running a third-party software VPN appliance.
AWS does not provide or maintain third-party software VPN appliances; however, there is a range of products provided by partners and open source communities.
AWS Direct Connect provides a dedicated private connection from a remote network to the VPC. Direct Connect can be combined with an AWS hardware VPN connection to create an IPsec-encrypted connection
AWS Site-to-Site VPN Options (2025)
As of November 2025, AWS Site-to-Site VPN includes five distinct options:
Standard VPN with VGW – Up to 1.25 Gbps per tunnel; terminates on a Virtual Private Gateway.
Standard VPN with TGW or Cloud WAN – Up to 1.25 Gbps per tunnel; terminates on a Transit Gateway or AWS Cloud WAN. Supports ECMP for higher aggregate bandwidth.
Large Bandwidth Tunnel with TGW – Up to 5 Gbps per tunnel (launched November 2025); a 4x improvement over the standard 1.25 Gbps limit. Ideal for bandwidth-intensive hybrid applications, big data migrations, and disaster recovery.
VPN Concentrator – Simplifies multi-site connectivity for distributed enterprises (launched November 2025). Supports up to 100 low-bandwidth remote sites (under 100 Mbps each) through a single Transit Gateway attachment with 5 Gbps aggregate bandwidth.
Accelerated VPN – Uses AWS Global Accelerator to route traffic through the nearest AWS edge location, reducing internet distance and improving performance. Supported on Transit Gateway.
Private IP VPN – Enables Site-to-Site VPN connections over AWS Direct Connect using private IP addresses. Encrypts DX traffic between on-premises networks and AWS without traversing the public internet. Requires Transit Gateway.
VPN Components
Virtual Private Gateway – VGW
A virtual private gateway is the VPN concentrator on the AWS side of the VPN connection
Supports standard bandwidth (up to 1.25 Gbps per tunnel)
Does not support IPv6 for Site-to-Site VPN connections
Does not support ECMP
Customer Gateway – CGW
A customer gateway is a physical device or software application on the customer side of the VPN connection.
When a VPN connection is created, the VPN tunnel comes up when traffic is generated from the remote side of the VPN connection.
By default, VGW is not the initiator; CGW must bring up the tunnels for the Site-to-Site VPN connection by generating traffic and initiating the Internet Key Exchange (IKE) negotiation process.
If the VPN connection experiences a period of idle time, usually 10 seconds, depending on the configuration, the tunnel may go down. To prevent this, a network monitoring tool to generate keepalive pings; for e.g. by using IP SLA.
Transit Gateway
A transit gateway is a transit hub that can be used to interconnect VPCs and on-premises networks.
A Site-to-Site VPN connection on a transit gateway can support either IPv4 traffic or IPv6 traffic inside the VPN tunnels.
Supports ECMP (Equal Cost Multi-Path) routing for aggregating bandwidth across multiple VPN tunnels (up to 50 Gbps).
Supports large bandwidth tunnels (up to 5 Gbps per tunnel).
Supports IPv6 addresses for outer tunnel IPs (announced July 2025), enabling full IPv6 migration (IPv6-in-IPv6) and IPv4-in-IPv6 configurations.
Supports VPN Concentrator attachments for multi-site connectivity.
Supports Private IP VPN connections over Direct Connect.
AWS Cloud WAN
AWS Cloud WAN is a managed wide area networking service for building and managing global networks.
Site-to-Site VPN connections can be attached to Cloud WAN core networks for global hybrid connectivity.
Supports IPv6 outer tunnel IPs (same as Transit Gateway).
A Site-to-Site VPN connection offers two VPN tunnels between a VGW or a transit gateway on the AWS side, and a CGW (which represents a VPN device) on the remote (on-premises) side.
VPN Routing Options
For a VPN connection, the route table for the subnets should be updated with the type of routing (static or dynamic) that you plan to use.
Route tables determine where network traffic is directed. Traffic destined for the VPN connections must be routed to the virtual private gateway.
The type of routing can depend on the make and model of the CGW device
Static Routing
If your device does not support BGP, specify static routing.
Using static routing, the routes (IP prefixes) can be specified that should be communicated to the virtual private gateway.
Devices that don’t support BGP may also perform health checks to assist failover to the second tunnel when needed.
BGP Dynamic Routing
If the VPN device supports Border Gateway Protocol (BGP), specify dynamic routing with the VPN connection.
When using a BGP device, static routes need not be specified to the VPN connection because the device uses BGP for auto-discovery and to advertise its routes to the virtual private gateway.
BGP-capable devices are recommended as the BGP protocol offers robust liveness detection checks that can assist failover to the second VPN tunnel if the first tunnel goes down.
Only IP prefixes known to the virtual private gateway, either through BGP advertisement or static route entry, can receive traffic from the VPC.
Virtual private gateway does not route any other traffic destined outside of the advertised BGP, static route entries, or its attached VPC CIDR.
VPN Route Priority
Longest prefix match applies.
If the prefixes are the same, then the VGW prioritizes routes as follows, from most preferred to least preferred:
BGP propagated routes from an AWS Direct Connect connection
Manually added static routes for a Site-to-Site VPN connection
BGP propagated routes from a Site-to-Site VPN connection
Prefix with the shortest AS PATH is preferred for matching prefixes where each Site-to-Site VPN connection uses BGP
Path with the lowest multi-exit discriminators (MEDs) value is preferred when the AS PATHs are the same length and if the first AS in the AS_SEQUENCE is the same across multiple paths.
VPN Bandwidth and Throughput
Standard VPN Tunnel: Up to 1.25 Gbps per tunnel (default)
Large Bandwidth VPN Tunnel: Up to 5 Gbps per tunnel (available on Transit Gateway, launched November 2025)
Supports modifying tunnel bandwidth on existing VPN connections (announced May 2026) without changing IP addresses, CIDR blocks, or pre-shared keys
VPN Concentrator Tunnel: Up to 100 Mbps per tunnel, 5 Gbps aggregate per concentrator
ECMP (Transit Gateway): Up to 50 Gbps aggregate bandwidth using multiple VPN tunnels with ECMP configured (each flow limited to max bandwidth per tunnel)
Many factors affect realized bandwidth including packet size, traffic mix (TCP/UDP), shaping or throttling policies on intermediate networks, internet weather, and specific application requirements.
VPN Limitations
supports only IPSec tunnel mode. Transport mode is currently not supported.
supports only one VGW can be attached to a VPC at a time.
does not support IPv6 traffic on a virtual private gateway. (IPv6 is supported on Transit Gateway and Cloud WAN.)
does not support Path MTU Discovery.
does not support overlapping CIDR blocks for the networks. It is recommended to use non-overlapping CIDR blocks.
does not support transitive routing. So for traffic from on-premises to AWS via a virtual private gateway, it
does not support Internet connectivity through Internet Gateway
does not support Internet connectivity through NAT Gateway
does not support VPC Peered resources access through VPC Peering
However, Internet connectivity through NAT instance and VPC Interface Endpoint or PrivateLink services are accessible.
provides a bandwidth of 1.25 Gbps per tunnel for standard VPN connections. Large bandwidth tunnels support up to 5 Gbps per tunnel on Transit Gateway.
MTU is 1446 bytes and MSS is 1406 bytes. Jumbo frames are not supported.
VPN Tunnel Endpoint Lifecycle Control
The VPN Tunnel Endpoint Lifecycle Control feature enables scheduling endpoint replacements at a time that aligns with business and operational needs, prior to the service-mandated deadline.
Provides advanced notice of upcoming maintenance updates to help plan and minimize service disruptions.
When enabled, AWS notifies before performing tunnel endpoint replacements.
Users can accept the maintenance update at a convenient time or let it apply automatically by the deadline.
During a tunnel endpoint update, AWS applies replacement to one tunnel at a time to ensure continuous connectivity.
Available in most AWS commercial and GovCloud regions.
VPN Monitoring
AWS Site-to-Site VPN automatically sends notifications to the AWS Health Dashboard
AWS Site-to-Site VPN is integrated with CloudWatch with the following metrics available
TunnelState
The state of the tunnels.
For static VPNs, 0 indicates DOWN and 1 indicates UP.
For BGP VPNs, 1 indicates ESTABLISHED and 0 is used for all other states.
For both types of VPNs, values between 0 and 1 indicate at least one tunnel is not UP.
TunnelDataIn
The bytes received on the AWS side of the connection through the VPN tunnel from a customer gateway.
This metric counts the data after decryption.
TunnelDataOut
The bytes sent from the AWS side of the connection through the VPN tunnel to the customer gateway.
This metric counts the data before encryption.
ConcentratorBandwidthUsage
The bandwidth usage for a Site-to-Site VPN Concentrator connection.
Available only for VPN connections using a VPN Concentrator.
Units: Bits per second
Site-to-Site VPN Logs
VPN logs can be published to Amazon CloudWatch Logs for detailed analysis of VPN connection activity.
Provides tunnel activity logs for troubleshooting connectivity issues.
Amazon CloudWatch Network Synthetic Monitor
Supports hybrid monitors for networking built with AWS Direct Connect and AWS Site-to-Site VPN.
Provides proactive monitoring of hybrid connectivity health.
IPv6 Support for Site-to-Site VPN
Inner Tunnel IPv6: Supported on Transit Gateway and Cloud WAN. Allows IPv4 or IPv6 traffic inside VPN tunnels.
Outer Tunnel IPv6 (July 2025): Site-to-Site VPN now supports IPv6 addresses for outer tunnel IPs on Transit Gateway and Cloud WAN connections.
Enables full IPv6 migration with IPv6 addresses for both outer tunnel IPs and inner packet IPs (IPv6-in-IPv6).
Helps customers with IPv6-only network mandates meet regulatory and compliance needs.
IPv6 VPNs support the same throughput (Gbps and PPS), MTU, and route limits as IPv4 VPNs.
Note: Virtual private gateways do NOT support IPv6 for Site-to-Site VPN connections. IPv6 requires Transit Gateway or Cloud WAN.
VPN Concentrator (November 2025)
AWS Site-to-Site VPN Concentrator simplifies multi-site connectivity for distributed enterprises with many low-bandwidth remote sites.
Suitable for customers needing to connect 25+ remote sites to AWS, with each site needing low bandwidth (under 100 Mbps).
Allows up to 100 remote sites to connect through a single VPN Concentrator attachment to AWS Transit Gateway.
Provides 5 Gbps aggregate bandwidth shared across all connected sites.
Eliminates the need to deploy and manage multiple virtual appliances for HA and connectivity.
AWS manages high availability across multiple Availability Zones.
Can be used with eero integration for simplified remote site connectivity without manual tunnel configuration.
Quotas:
Up to 50 VPN Concentrators per Region
Up to 5 VPN Concentrators per Transit Gateway or Cloud WAN
Up to 100 remote sites per VPN Concentrator
VPN Connection Redundancy
A VPN connection is used to connect the customer network to a VPC.
Each VPN connection has two tunnels to help ensure connectivity in case one of the VPN connections becomes unavailable, with each tunnel using a unique virtual private gateway public IP address.
Both tunnels should be configured for redundancy.
When one tunnel becomes unavailable, for e.g. down for maintenance, network traffic is automatically routed to the available tunnel for that specific VPN connection.
To protect against a loss of connectivity in case the customer gateway becomes unavailable, a second VPN connection can be set up to the VPC and virtual private gateway by using a second customer gateway.
Customer gateway IP address for the second VPN connection must be publicly accessible.
By using redundant VPN connections and CGWs, maintenance on one of the customer gateways can be performed while traffic continues to flow over the second customer gateway’s VPN connection.
Dynamically routed VPN connections using the Border Gateway Protocol (BGP) are recommended, if available, to exchange routing information between the customer gateways and the virtual private gateways.
Statically routed VPN connections require static routes for the network to be entered on the customer gateway side.
BGP-advertised and statically entered route information allows gateways on both sides to determine which tunnels are available and reroute traffic if a failure occurs.
Multiple Site-to-Site VPN Connections
VPC has an attached virtual private gateway, and the remote network includes a customer gateway, which must be configured to enable the
VPN connection.
Routing must be set up so that any traffic from the VPC bound for the remote network is routed to the virtual private gateway.
Each VPN has two tunnels associated with it that can be configured on the customer router, as is not a single point of failure
Multiple VPN connections to a single VPC can be created, and a second CGW can be configured to create a redundant connection to the same external location or to create VPN connections to multiple geographic locations.
VPN CloudHub
VPN CloudHub can be used to provide secure communication between multiple on-premises sites if you have multiple VPN connections
VPN CloudHub operates on a simple hub-and-spoke model using a Virtual Private gateway in a detached mode that can be used without a VPC.
Design is suitable for customers with multiple branch offices and existing
Internet connections who’d like to implement a convenient, potentially low-cost hub-and-spoke model for primary or backup connectivity between these remote offices
Note: For large-scale multi-site connectivity (25+ sites), consider using the newer VPN Concentrator feature with Transit Gateway, which provides a managed, scalable alternative.
VPN CloudHub architecture with blue dashed lines indicates network
traffic between remote sites being routed over their VPN connections.
AWS VPN CloudHub requires a virtual private gateway with multiple customer gateways.
Each customer gateway must use a unique Border Gateway Protocol (BGP) Autonomous System Number (ASN)
Customer gateways advertise the appropriate routes (BGP prefixes) over their VPN connections.
Routing advertisements are received and re-advertised to each BGP peer, enabling each site to send data to and receive data from the other sites.
Routes for each spoke must have unique ASNs and the sites must not have overlapping IP ranges.
Each site can also send and receive data from the VPC as if they were using a standard VPN connection.
Sites that use AWS Direct Connect connections to the virtual private gateway can also be part of the AWS VPN CloudHub.
To configure the AWS VPN CloudHub,
multiple customer gateways can be created, each with the unique public IP address of the gateway and the ASN.
a VPN connection can be created from each customer gateway to a common virtual private gateway.
each VPN connection must advertise its specific BGP routes. This is done using the network statements in the VPN configuration files for the VPN connection.
Private IP VPN over Direct Connect
AWS Site-to-Site VPN Private IP VPN enables deploying VPN connections over Direct Connect using private IP addresses.
Direct Connect provides a private, dedicated connection but is not encrypted. Private IP VPN adds IPSec encryption to DX traffic.
Requires a Transit Gateway with a Direct Connect Gateway attachment.
Traffic stays on the AWS private network and never traverses the public internet.
Satisfies security and compliance regulations requiring encryption at layer 3 for dedicated connections.
Configuration:
Create or use an existing Transit Gateway with a private IP CIDR block.
Establish a Direct Connect connection and Transit VIF to a Direct Connect Gateway.
Create a Private IP VPN connection specifying private outside IP address type.
Accelerated Site-to-Site VPN
An accelerated VPN connection uses AWS Global Accelerator to route traffic from the on-premises network to the nearest AWS edge location.
Reduces the distance over which data is shared on the internet by leveraging the AWS global fiber network.
Improves performance for VPN connections where the customer gateway is geographically distant from the AWS Region.
Requires a Transit Gateway (not supported on VGW).
Each accelerated VPN connection uses two Global Accelerator resources (one per tunnel).
Default quota: 10 accelerated Site-to-Site VPN connections per Region (adjustable).
Virtual private gateways per Region: 5 (adjustable)
Site-to-Site VPN connections per Region: 50 (adjustable)
Site-to-Site VPN connections per virtual private gateway: 10 (adjustable)
Accelerated VPN connections per Region: 10 (adjustable)
Large Bandwidth Tunnel connections per Region: 50 (adjustable)
VPN Concentrators per Region: 50 (adjustable)
VPN Concentrators per Transit Gateway or Cloud WAN: 5 (adjustable)
Remote sites per VPN Concentrator: 100 (adjustable)
Dynamic routes advertised from CGW to VPN on VGW: 100 (not adjustable)
Routes advertised from VPN on VGW to CGW: 1,000 (not adjustable)
Dynamic routes advertised from CGW to VPN on Transit Gateway: 1,000 (not adjustable)
Routes advertised from VPN on Transit Gateway to CGW: 5,000 (not adjustable)
AWS Certification Exam Practice Questions
Questions are collected from Internet and the answers are marked as per my knowledge and understanding (which might differ with yours).
AWS services are updated everyday and both the answers and questions might be outdated soon, so research accordingly.
AWS exam questions are not updated to keep up the pace with AWS updates, so even if the underlying feature has changed the question might not be updated
Open to further feedback, discussion and correction.
You have in total 5 offices, and the entire employee-related information is stored under AWS VPC instances. Now all the offices want to connect the instances in VPC using VPN. Which of the below help you to implement this?
you can have redundant customer gateways between your data center and your VPC
you can have multiple locations connected to the AWS VPN CloudHub
You have to define 5 different static IP addresses in route table.
1 and 2
1,2 and 3
You have in total of 15 offices, and the entire employee-related information is stored under AWS VPC instances. Now all the offices want to connect the instances in VPC using VPN. What problem do you see in this scenario?
You can not create more than 1 VPN connections with single VPC (Can be created)
You can not create more than 10 VPN connections with single VPC (soft limit can be extended)
When you create multiple VPN connections, the virtual private gateway can not sends network traffic to the appropriate VPN connection using statically assigned routes. (Can route the traffic to correct connection)
Statically assigned routes cannot be configured in case of more than 1 VPN with the virtual private gateway. (can be configured)
None of above
You have been asked to virtually extend two existing data centers into AWS to support a highly available application that depends on existing, on-premises resources located in multiple data centers and static content that is served from an Amazon Simple Storage Service (S3) bucket. Your design currently includes a dual-tunnel VPN connection between your CGW and VGW. Which component of your architecture represents a potential single point of failure that you should consider changing to make the solution more highly available?
Add another VGW in a different Availability Zone and create another dual-tunnel VPN connection.
Add another CGW in a different data center and create another dual-tunnel VPN connection. (Refer link)
Add a second VGW in a different Availability Zone, and a CGW in a different data center, and create another dual-tunnel.
No changes are necessary: the network architecture is currently highly available.
You are designing network connectivity for your fat client application. The application is designed for business travelers who must be able to connect to it from their hotel rooms, cafes, public Wi-Fi hotspots, and elsewhere on the Internet. You do not want to publish the application on the Internet. Which network design meets the above requirements while minimizing deployment and operational costs? [PROFESSIONAL]
Implement AWS Direct Connect, and create a private interface to your VPC. Create a public subnet and place your application servers in it. (High Cost and does not minimize deployment)
Implement Elastic Load Balancing with an SSL listener that terminates the back-end connection to the application. (Needs to be published to internet)
Configure an IPsec VPN connection, and provide the users with the configuration details. Create a public subnet in your VPC, and place your application servers in it. (Instances still in public subnet are internet accessible)
Configure an SSL VPN solution in a public subnet of your VPC, then install and configure SSL VPN client software on all user computers. Create a private subnet in your VPC and place your application servers in it. (Cost effective and can be in private subnet as well. Note: AWS Client VPN is the managed alternative for this use case.)
You are designing a connectivity solution between on-premises infrastructure and Amazon VPC Your server’s on-premises will De communicating with your VPC instances You will De establishing IPSec tunnels over the internet You will be using VPN gateways and terminating the IPsec tunnels on AWS-supported customer gateways. Which of the following objectives would you achieve by implementing an IPSec tunnel as outlined above? (Choose 4 answers) [PROFESSIONAL]
End-to-end protection of data in transit
End-to-end Identity authentication
Data encryption across the Internet
Protection of data in transit over the Internet
Peer identity authentication between VPN gateway and customer gateway
Data integrity protection across the Internet
A development team that is currently doing a nightly six-hour build which is lengthening over time on-premises with a large and mostly under utilized server would like to transition to a continuous integration model of development on AWS with multiple builds triggered within the same day. However, they are concerned about cost, security and how to integrate with existing on-premises applications such as their LDAP and email servers, which cannot move off-premises. The development environment needs a source code repository; a project management system with a MySQL database resources for performing the builds and a storage location for QA to pick up builds from. What AWS services combination would you recommend to meet the development team’s requirements? [PROFESSIONAL]
A Bastion host Amazon EC2 instance running a VPN server for access from on-premises, Amazon EC2 for the source code repository with attached Amazon EBS volumes, Amazon EC2 and Amazon RDS MySQL for the project management system, EIP for the source code repository and project management system, Amazon SQL for a build queue, An Amazon Auto Scaling group of Amazon EC2 instances for performing builds and Amazon Simple Email Service for sending the build output. (Bastion is not for VPN connectivity also SES should not be used)
An AWS Storage Gateway for connecting on-premises software applications with cloud-based storage securely, Amazon EC2 for the resource code repository with attached Amazon EBS volumes, Amazon EC2 and Amazon RDS MySQL for the project management system, EIPs for the source code repository and project management system, Amazon Simple Notification Service for a notification initiated build, An Auto Scaling group of Amazon EC2 instances for performing builds and Amazon S3 for the build output. (Storage Gateway does provide secure connectivity but still needs VPN. SNS alone cannot handle builds)
An AWS Storage Gateway for connecting on-premises software applications with cloud-based storage securely, Amazon EC2 for the resource code repository with attached Amazon EBS volumes, Amazon EC2 and Amazon RDS MySQL for the project management system, EIPs for the source code repository and project management system, Amazon SQS for a build queue, An Amazon Elastic Map Reduce (EMR) cluster of Amazon EC2 instances for performing builds and Amazon CloudFront for the build output. (Storage Gateway does not provide secure connectivity, still needs VPN. EMR is not ideal for performing builds as it needs normal EC2 instances)
A VPC with a VPN Gateway back to their on-premises servers, Amazon EC2 for the source-code repository with attached Amazon EBS volumes, Amazon EC2 and Amazon RDS MySQL for the project management system, EIPs for the source code repository and project management system, SQS for a build queue, An Auto Scaling group of EC2 instances for performing builds and S3 for the build output. (VPN gateway is required for secure connectivity. SQS for build queue and EC2 for builds)
A company has 50 branch offices and wants to connect all of them to AWS. Each branch has bandwidth requirements under 50 Mbps. Which AWS VPN solution is most cost-effective and operationally simple?
Create 50 individual Site-to-Site VPN connections to a Transit Gateway (Works but higher cost and operational overhead with 50 separate VPN connections)
Use a VPN Concentrator on Transit Gateway to connect all branches through a single attachment (VPN Concentrator supports up to 100 sites with under 100 Mbps each, single TGW attachment simplifies management)
Use VPN CloudHub with a Virtual Private Gateway (VPN CloudHub works but limited to VGW capabilities and doesn’t scale as easily)
A company requires encrypted connectivity between their on-premises data center and AWS over their existing Direct Connect connection. The traffic must not traverse the public internet. Which solution meets these requirements?
Configure a standard Site-to-Site VPN over the internet as backup to Direct Connect (Traffic traverses the public internet)
Configure a Private IP VPN connection over Direct Connect using Transit Gateway (Private IP VPN encrypts DX traffic using private IP addresses without internet traversal)
Enable MACsec on Direct Connect and use VGW for VPN termination (MACsec provides L2 encryption but VGW doesn’t support Private IP VPN)
Use AWS Client VPN over Direct Connect (Client VPN is for remote user access, not site-to-site connectivity)
A company needs to migrate large datasets to AWS and requires more than 1.25 Gbps of VPN bandwidth per tunnel. What should they configure?
Create multiple standard VPN connections and enable ECMP on a VGW (VGW does not support ECMP)
Use Accelerated VPN with Global Accelerator to increase per-tunnel bandwidth (Accelerated VPN improves latency but does not increase per-tunnel bandwidth beyond standard limits)
Configure a Large Bandwidth Tunnel VPN connection on Transit Gateway for up to 5 Gbps per tunnel (Large Bandwidth Tunnels support up to 5 Gbps per tunnel on TGW)
Configure Direct Connect with 10 Gbps dedicated connection (Meets bandwidth needs but is not a VPN solution and takes longer to provision)
An organization has VPN connections from multiple branch offices to AWS. The VPN performance is poor because the branches are far from the AWS Region. What can improve VPN performance without changing the on-premises equipment? (Choose 2)
Enable Accelerated VPN using AWS Global Accelerator on Transit Gateway (Routes traffic to the nearest AWS edge location to reduce internet distance)
Enable VPN CloudHub on a Virtual Private Gateway (VPN CloudHub is for inter-site communication, not for improving performance)
Use Large Bandwidth Tunnels (5 Gbps) on Transit Gateway (Higher per-tunnel bandwidth can improve throughput for bandwidth-constrained connections)
Configure Private IP VPN over Direct Connect (Requires Direct Connect infrastructure, changes the connectivity model)
Add more VPN tunnels with ECMP on VGW (VGW does not support ECMP)
is a horizontally scaled, redundant, and highly available component that allows communication between instances in your VPC and the internet.
imposes no availability risks or bandwidth constraints on your network traffic.
serves two purposes: to provide a target in the VPC route tables for internet-routable traffic and to perform NAT for instances that have not been assigned public IPv4 addresses.
enables instances in a private subnet to connect to the internet or other AWS services, but prevents the Internet from initiating connections with the instances.
Public NAT gateway allows instances in private subnets to connect to the internet through the NAT gateway’s Elastic IP address.
Private NAT gateway allows instances in private subnets to connect to other VPCs or the on-premises network using its private IP address for source NAT.
Regional NAT Gateway (New – Nov 2025) – automatically expands across Availability Zones based on workload presence. Unlike standard (zonal) NAT gateways which operate in a single AZ, regional NAT gateways follow workloads to provide automatic high availability without requiring a public subnet to host the gateway.
Egress Only Internet Gateway
NAT devices are not supported for IPv6 traffic, use an Egress-only Internet gateway instead
Egress-only Internet gateway is a horizontally scaled, redundant, and highly available VPC component
Egress-only Internet gateway allows outbound communication over IPv6 from instances in the VPC to the Internet and prevents the Internet from initiating an IPv6 connection with your instances.
VPC endpoint provides a private connection from VPC to supported AWS services and VPC endpoint services powered by PrivateLink without requiring an internet gateway, NAT device, VPN connection, or AWS Direct Connect connection.
Instances in the VPC do not require public IP addresses to communicate with resources in the service. Traffic between the VPC and the other service does not leave the Amazon network.
VPC Endpoints are virtual devices and are horizontally scaled, redundant, and highly available VPC components that allow communication between instances in the VPC and services without imposing availability risks or bandwidth constraints on the network traffic.
VPC Endpoints are of three types
Interface Endpoints – is an elastic network interface with a private IP address that serves as an entry point for traffic destined to supported services.
Gateway Endpoints – is a gateway that is a target for a specified route in your route table, used for traffic destined to a supported AWS service. Currently only Amazon S3 and DynamoDB.
Resource Endpoints (New – Dec 2024) – enables private access to a specific resource (e.g., RDS database, IP address, or domain name) in another VPC or on-premises environment shared via AWS RAM, without requiring an NLB.
Cross-Region PrivateLink (Nov 2025) – Interface VPC endpoints now support cross-region connectivity, breaking the previous limitation that endpoints were regional-only. This enables connecting to VPC endpoint services hosted in other AWS Regions within the same partition.
provides private connectivity between VPCs, AWS services, and your on-premises networks without exposing your traffic to the public internet.
helps privately expose a service/application residing in one VPC (service provider) to other VPCs (consumer) within an AWS Region in a way that only consumer VPCs initiate connections to the service provider VPC.
With ALB as a target of NLB, ALB’s advanced routing capabilities can be combined with AWS PrivateLink.
VPC Resource Gateway (Dec 2024) – allows sharing any VPC resource (RDS databases, domain names, IP addresses) via AWS RAM. Consumers access these resources privately using VPC endpoints without needing an NLB, simplifying hybrid networking.
Cross-Region Connectivity (Nov 2025) – PrivateLink now supports native cross-region access for both AWS services and customer endpoint services, enabling global private connectivity from a single Region deployment.
enables networking connection between two VPCs to route traffic between them using private IPv4 addresses or IPv6 addresses
connections can be created between your own VPCs, or with a VPC in another AWS account.
enables full bidirectional connectivity between the VPCs
supports inter-region VPC peering connection
Inter-region peering now supports jumbo frames (up to 8500 bytes MTU) and full instance bandwidth (Mar 2025)
uses existing underlying AWS infrastructure
does not have a single point of failure for communication or a bandwidth bottleneck.
VPC Peering connections have limitations
cannot be used with Overlapping CIDR blocks
does not provide Transitive peering
does not support Edge to Edge routing through Gateway or private connection
is best used when resources in one VPC must communicate with resources in another VPC, the environment of both VPCs is controlled and secured, and the number of VPCs to be connected is less than 10
supports a limit of 125 active peering connections per VPC
Simplified Billing (Apr 2025) – AWS simplified VPC Peering billing; no changes to data transfer pricing but billing structure is streamlined.
VPN CloudHub
AWS VPN CloudHub allows you to securely communicate from one site to another using AWS Managed VPN or Direct Connect
AWS VPN CloudHub operates on a simple hub-and-spoke model that can be used with or without a VPC
AWS VPN CloudHub can be used if you have multiple branch offices and existing internet connections and would like to implement a convenient, potentially low cost hub-and-spoke model for primary or backup connectivity between these remote offices.
AWS VPN CloudHub leverages VPC virtual private gateway with multiple gateways, each using unique BGP autonomous system numbers (ASNs).
⚠️ Note: Transit VPC is a legacy architecture pattern. AWS recommends using AWS Transit Gateway or AWS Cloud WAN for new deployments, which provide managed, highly available hub-and-spoke connectivity without the operational overhead of managing EC2-based virtual appliances.
A transit VPC is a common strategy for connecting multiple, geographically disperse VPCs and remote networks in order to create a global network transit center.
A transit VPC simplifies network management and minimizes the number of connections required to connect multiple VPCs and remote networks
Transit VPC can be used to support important use cases
Private Networking – You can build a private network that spans two or more AWS Regions.
Shared Connectivity – Multiple VPCs can share connections to data centers, partner networks, and other clouds.
Cross-Account AWS Usage – The VPCs and the AWS resources within them can reside in multiple AWS accounts.
Transit VPC design helps implement more complex routing rules, such as network address translation between overlapping network ranges, or to add additional network-level packet filtering or inspection.
Transit VPC
supports Transitive routing using the overlay VPN network — allowing for a simpler hub and spoke design.
supports network address translation between overlapping network ranges.
supports vendor functionality around advanced security (layer 7 firewall/IPS/IDS) using third-party software on EC2
leverages instance-based routing that increases costs while lowering availability and limiting the bandwidth.
Customers are responsible for managing the HA and redundancy of EC2 instances running the third-party vendor virtual appliance
is a highly available and scalable service to consolidate the AWS VPC routing configuration for a region with a hub-and-spoke architecture.
is a Regional resource and can connect thousands of VPCs within the same AWS Region.
TGWs across different regions can peer with each other to enable VPC communications within the same or different regions.
provides simpler VPC-to-VPC communication management over VPC Peering with a large number of VPCs.
enables you to attach VPCs (across accounts) and VPN connections in the same Region and route traffic between them.
support dynamic and static routing between attached VPCs and VPN connections
removes the need for using full mesh VPC Peering and Transit VPC
Transit Gateway Flow Logs – enables capturing detailed telemetry (source/destination IPs, ports, protocol, traffic counters, timestamps) for all network flows traversing the Transit Gateway. Logs can be published to CloudWatch Logs, S3, or Firehose.
Flexible Cost Allocation (Nov 2025) – provides granular control over how Transit Gateway data processing costs are allocated across AWS accounts within AWS Organizations.
AWS Cloud WAN
is a managed wide area networking (WAN) service that helps build, manage, and monitor a unified global network connecting cloud and on-premises resources.
provides a central dashboard and network policies to create a global network spanning multiple locations, removing the need to configure and manage different networks using different technologies.
uses a policy-based automation system to define network segments, attach VPCs, VPN connections, and SD-WAN products.
simplifies global network management compared to manually managing Transit Gateways across regions.
key features include:
Central Dashboard – manage branch offices, data centers, VPN connections, SD-WAN, VPCs, and Transit Gateways from one place.
Network Policies – define how traffic is routed between segments with policy-based controls.
Service Insertion (2024) – streamlines integrating security and inspection services (e.g., Network Firewall) into global networks.
Routing Policy (Nov 2025) – enables route filtering, summarization, and BGP path manipulation for fine-grained traffic control at scale.
Security Group Referencing & Enhanced DNS (Jun 2025) – simplifies security group management and DNS resolution across Cloud WAN segments.
can be used as a migration path from Transit Gateway for organizations needing global, multi-Region network management.
available in AWS GovCloud (US) Regions as of Jun 2026.
VPC provides the option of creating an IPsec VPN connection between remote customer networks and their VPC over the internet
AWS managed VPN endpoint includes automated multi–data center redundancy & failover built into the AWS side of the VPN connection
AWS managed VPN consists of two parts
Virtual Private Gateway (VPG) on AWS side
Customer Gateway (CGW) on the on-premises data center
AWS Site-to-Site VPN only provides Site-to-Site VPN connectivity. It does not provide Point-to-Site VPC connectivity (use AWS Client VPN for that).
Virtual Private Gateway are Highly Available as it represents two distinct VPN endpoints, physically located in separate data centers to increase the availability of the VPN connection.
High Availability on the on-premises data center must be handled by creating additional Customer Gateway.
AWS Site-to-Site VPN connections are low cost, quick to setup and start with compared to Direct Connect. However, they are not reliable as they traverse through Internet.
5 Gbps Bandwidth Tunnels (Nov 2025) – supports VPN connections with up to 5 Gbps bandwidth per tunnel, a 4x improvement from the previous 1.25 Gbps limit. Beneficial for bandwidth-intensive hybrid applications, big data migrations, and disaster recovery. Bandwidth can be modified on existing connections without changing on-premises configuration (May 2026).
IPv6 Support for Outer Tunnel IPs (Jul 2025) – supports IPv6 addresses on outer tunnel IPs, enabling full IPv6-only VPN connectivity (IPv6-in-IPv6) and mixed (IPv4-in-IPv6) configurations without IPv6>IPv4>IPv6 translation.
VPN Concentrator (Nov 2025) – a new feature that simplifies multi-site connectivity for distributed enterprises with 25+ remote sites needing low bandwidth (under 100 Mbps each). Connects multiple remote sites through a single VPN attachment to Transit Gateway with 5 Gbps aggregate bandwidth.
AWS Client VPN
is a fully managed, scalable VPN service that provides an endpoint for users to establish a secure remote access (Point-to-Site) connection to the AWS network.
uses OpenVPN-based VPN client software for secure connectivity.
handles Point-to-Site VPN connectivity that AWS Site-to-Site VPN does not provide (e.g., remote worker/mobile access).
supports authentication via Active Directory, SAML-based federated authentication, and mutual certificate authentication.
IPv6 Connectivity (Aug 2025) – now supports full IPv6 connectivity for Client VPN endpoints, allowing connections to IPv6 resources in VPCs and from clients on IPv6 networks.
Software VPN
VPC offers the flexibility to fully manage both sides of the VPC connectivity by creating a VPN connection between your remote network and a software VPN appliance running in your VPC network.
Software VPNs help manage both ends of the VPN connection either for compliance purposes or for leveraging gateway devices that are not currently supported by Amazon VPC’s VPN solution.
Software VPNs allows you to handle Point-to-Site connectivity (though AWS Client VPN is now the recommended managed alternative).
Software VPNs, with the above design, introduces a single point of failure and needs to be handled.
AWS Direct Connect helps establish a dedicated private connection between an on-premises network and AWS.
Direct Connect can reduce network costs, increase bandwidth throughput, and provide a more consistent network experience than internet-based or VPN connections
Direct Connect uses industry-standard VLANs to access EC2 instances running within a VPC using private IP addresses
Direct Connect lets you establish
Dedicated Connection: A 1G, 10G, or 100G physical Ethernet connection associated with a single customer through AWS.
Hosted Connection: A physical Ethernet connection that an AWS Direct Connect Partner provisions on behalf of a customer. Speeds range from 50 Mbps to 10 Gbps.
Direct Connect provides the following Virtual Interfaces
Private virtual interface – to access a VPC using private IP addresses.
Public virtual interface – to access all AWS public services using public IP addresses.
Transit virtual interface – to access one or more transit gateways associated with Direct Connect gateways.
Direct Connect connections are not redundant as each connection consists of a single dedicated connection between ports on your router and an Amazon router
Direct Connect High Availability can be configured using
Multiple Direct Connect connections
Back-up IPSec VPN connection
SiteLink – enables sending data between AWS Direct Connect locations to create private network connections between offices and data centers in a global network, bypassing AWS Regions. Data travels over the shortest path between locations using the AWS global network backbone.
VIF Rate Limiters (Jun 2026) – supports Virtual Interface Rate Limiters on dedicated connections to prevent network congestion caused by unexpected traffic spikes on a VIF, protecting other VIFs on the same connection.
LAGs
Direct Connect link aggregation group (LAG) is a logical interface that uses the Link Aggregation Control Protocol (LACP) to aggregate multiple connections at a single AWS Direct Connect endpoint, allowing you to treat them as a single, managed connection.
LAGs need the following
All connections in the LAG must use the same bandwidth.
A maximum of four connections in a LAG. Each connection in the LAG counts toward the overall connection limit for the Region.
All connections in the LAG must terminate at the same AWS Direct Connect endpoint.
offers a Free Tier – fully managed 500 Mbps interconnect to another CSP at no charge on the AWS side (May 2026).
eliminates complex multicloud networking setups that previously required physical Direct Connect connections and manual peering arrangements.
Amazon VPC Lattice
is an application networking service that consistently connects, monitors, and secures communications between services and resources across VPCs and accounts.
automatically manages network connectivity and application layer routing between services across different VPCs and AWS accounts.
abstracts IP address dependencies, allowing applications to communicate securely without direct network routing.
supports HTTP, HTTPS, gRPC, TLS, and TCP protocols.
key features include:
Service Networks – logical grouping of services with shared access and observability policies.
Service Network VPC Endpoints – allows VPCs to connect to service networks via VPC endpoints.
VPC Resources Support (re:Invent 2024) – enables connectivity to TCP resources such as databases, domain names, and IP addresses across VPCs and accounts.
Auth Policies – fine-grained access control using IAM-based policies at the service network and service level.
can replace complex Transit Gateway and PrivateLink configurations for service-to-service communication within a Region.
does not natively support cross-Region service access; requires a proxy solution for external Region connectivity.
Amazon VPC Route Server
is a new managed service (GA Apr 2025) that enables dynamic routing within Amazon VPC using Border Gateway Protocol (BGP).
allows deploying endpoints in a VPC and peering them with virtual appliances to advertise routes using BGP.
filters received routes using standard BGP attributes and propagates selected routes to specified VPC route tables.
dynamically updates VPC and internet gateway route tables with preferred IPv4 or IPv6 routes for routing fault tolerance.
eliminates the need for complex scripting or Lambda-based failover mechanisms for virtual appliance routing.
key use cases:
Automatic active/standby failover for inspection appliances
Dynamic routing between cloud applications and on-premises systems via virtual appliances
Integration with Transit Gateway for centralized inspection architectures
Logging Enhancements (Jun 2025) – provides real-time monitoring of BGP and BFD session states, historical peer-to-peer session data, with delivery via CloudWatch, S3, Data Firehose, or AWS CLI.
