Hello @Bas Pruijn ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that one of your customers is looking for a VPN Applicance running in Azure to support at least 10,000 simultaneous IPSEC connections.
All the different options available for organizations to establish remote access for their users by using Azure networking services can be found in the below document:
https://learn.microsoft.com/en-us/azure/networking/working-remotely-support?toc=%2Fazure%2Fvpn-gateway%2Ftoc.json
You can use Azure VPN gateway but as you mentioned, for 10,000 connections, you would need a VPN gateway of at least VpnGw5 SKU which will have 128 P2S connections included, and rest 129-10,000 connections will be charged at $0.01/hour per connection + Outbound P2S (Point-to-Site) VPN data transfer will be charged at standard data transfer rates.
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/work-remotely-support
https://learn.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-about-vpngateways#gwsku
https://azure.microsoft.com/en-us/pricing/details/vpn-gateway/
You can use Azure Virtual WAN, where each Virtual WAN hub supports up to 100,000 remote user connections and the aggregate throughput per Virtual WAN User VPN (Point-to-site) gateway is 200 Gbps. However, you would need to check the pricing before making a decision.
A Standard Virtual WAN Hub costs $0.25/hour + Standard Virtual WAN Hub Data Processing is charged at $0.02/GB + VPN P2S Scale Unit is charged at $0.361/hour (500 Mbps per Scale Unit, per Deployment Hour) + VPN P2S Connection Unit is charged at $0.013/hour (1 per Connection Unit per Deployment Hour)
Refer: https://learn.microsoft.com/en-us/azure/virtual-wan/work-remotely-support
https://learn.microsoft.com/en-us/azure/azure-resource-manager/management/azure-subscription-service-limits#virtual-wan-limits
https://azure.microsoft.com/en-us/pricing/details/virtual-wan/
For IPsec connections, the above 2 would be the native Azure products/services that you can use for remote support.
If the above native Azure solutions doesn't work for you, you can utilize third-party Network Virtual Appliances (NVAs) from Azure Marketplace to provide Point-to-site VPN for your users.
Refer: https://learn.microsoft.com/en-us/azure/vpn-gateway/nva-work-remotely-support
Some of the recommended NVAs that are available in Azure Marketplace are as below:
Barracuda CloudGen Access, CloudGuard Network Security, Cisco AnyConnect, Fortinet FortiGate Next-Generation Firewall, etc.
Kindly let us know if the above helps or you need further assistance on this issue.
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