hybrid-cloud-networking

# Hybrid Cloud Networking

Configure secure, high-performance connectivity between on-premises and cloud environments using VPN, Direct Connect, and ExpressRoute.

## Purpose

Establish secure, reliable network connectivity between on-premises data centers and cloud providers (AWS, Azure, GCP).

## When to Use

- Connect on-premises to cloud
- Extend datacenter to cloud
- Implement hybrid active-active setups
- Meet compliance requirements
- Migrate to cloud gradually

## Connection Options

### AWS Connectivity

#### 1. Site-to-Site VPN
- IPSec VPN over internet
- Up to 1.25 Gbps per tunnel
- Cost-effective for moderate bandwidth
- Higher latency, internet-dependent

```hcl
resource "aws_vpn_gateway" "main" {
  vpc_id = aws_vpc.main.id
  tags = {
    Name = "main-vpn-gateway"
  }
}

resource "aws_customer_gateway" "main" {
  bgp_asn    = 65000
  ip_address = "203.0.113.1"
  type       = "ipsec.1"
}

resource "aws_vpn_connection" "main" {
  vpn_gateway_id      = aws_vpn_gateway.main.id
  customer_gateway_id = aws_customer_gateway.main.id
  type                = "ipsec.1"
  static_routes_only  = false
}
```

#### 2. AWS Direct Connect
- Dedicated network connection
- 1 Gbps to 100 Gbps
- Lower latency, consistent bandwidth
- More expensive, setup time required

**Reference:** See `references/direct-connect.md`

### Azure Connectivity

#### 1. Site-to-Site VPN
```hcl
resource "azurerm_virtual_network_gateway" "vpn" {
  name                = "vpn-gateway"
  location            = azurerm_resource_group.main.location
  resource_group_name = azurerm_resource_group.main.name

  type     = "Vpn"
  vpn_type = "RouteBased"
  sku      = "VpnGw1"

  ip_configuration {
    name                          = "vnetGatewayConfig"
    public_ip_address_id          = azurerm_public_ip.vpn.id
    private_ip_address_allocation = "Dynamic"
    subnet_id                     = azurerm_subnet.gateway.id
  }
}
```

#### 2. Azure ExpressRoute
- Private connection via connectivity provider
- Up