> For the complete documentation index, see [llms.txt](https://docs.console.zenlayer.com/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.console.zenlayer.com/welcome/cloud-networking/get-started/create-a-layer-3-connection.md).

# Create a Layer 3 Connection

If you need a Layer 3 network connection - the [**cloud router**](/welcome/cloud-networking/overview/concepts.md#cloud-router), you can follow the steps as shown below.

## Prerequisites

* You have [**signed up an account**](/welcome/platform/account-management/create-an-account.md) with your email and sign in to [**zenConsole**](https://console.zenlayer.com/).
* If you need to connect to your cloud services, your public cloud provider should be one of the following: Amazon Web Service, Tencent Cloud, Google Cloud, Alibaba Cloud, and Microsoft Azure.\
  More public cloud providers will be supported soon.
* For VPC connection, instances in subnets with the same IP range can not communicate with each other. Please plan the IP ranges of your subnets reasonably in advance in case of abnormal connection.

## Networking Modes

Before creating a Layer 3 cloud router, we recommend that you understand the available networking modes. A Layer 3 cloud router supports two networking modes — **Connection Mode** and **Access Point Mode** — designed for different networking scales and interconnection needs. Choose the one that fits your number of access points, topology planning, and billing preferences.

<table><thead><tr><th width="160">Networking Mode</th><th>Interconnection</th><th>Best For</th><th>Billing</th></tr></thead><tbody><tr><td><strong>Connection Mode</strong></td><td>You define the interconnection between access points on demand, building the topology you need with links established only between the access points that must communicate.</td><td>Recommended for networking scenarios with fewer access points.</td><td>Each interconnection can independently use <strong>fixed bandwidth</strong> or <strong>95th percentile</strong> billing, offering more flexible commercial billing.</td></tr><tr><td><strong>Access Point Mode</strong></td><td>Adopts a full-mesh topology by default, where all access points in the network are automatically interconnected without configuring each link.</td><td>Suitable for large-scale networking scenarios.</td><td>Only <strong>fixed bandwidth</strong> billing is supported for now.</td></tr></tbody></table>

{% hint style="info" %} <mark style="color:blue;">**Note**</mark>

<mark style="color:blue;">The networking mode is selected at creation. Choose it based on your actual networking plan.</mark>
{% endhint %}

### Connection Mode Configuration

In Connection Mode, you define the interconnection between access points on demand, establishing links only between the access points that must communicate to build the topology you need. The configuration steps are as follows:

1. **Select the networking mode**: In the first step of creating a Layer 3 cloud router, select **Connection Mode**.
2. **Select the access point types**: Select the types of access points to connect (such as data center, public cloud, or elastic compute) and add them.
3. **Configure routing information**: For each access point, plan the interconnection IP address, Autonomous System Number (ASN), BFD, and advanced settings to enable network communication. See [**Configure Routing**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-routing-information.md) for details.
4. **Specify the interconnected access points**: Select the access points to interconnect and assign a **VLAN** to each interconnection, establishing links only between the access points that need to communicate.
5. **Select the billing mode and business bandwidth**: For each interconnection, select the billing mode (**fixed bandwidth** or **95th percentile**) and configure the business bandwidth. Each interconnection can use a billing mode independently.

### Access Point Mode Configuration

In Access Point Mode, a full-mesh topology is adopted by default, where all access points in the network are automatically interconnected without configuring each link, making the setup simpler. The configuration steps are as follows:

1. **Select the networking mode**: In the first step of creating a Layer 3 cloud router, select **Access Point Mode**. Once selected, all access points in the network are automatically interconnected in a full mesh.
2. **Select the access point types**: Select the types of access points to connect (such as data center, public cloud, or elastic compute) and add them.
3. **Configure routing information**: For each access point, plan the interconnection IP address, Autonomous System Number (ASN), VLAN, BFD, and advanced settings to enable network communication. See [**Configure Routing**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-routing-information.md) for details.
4. **Select the billing mode and business bandwidth**: Configure the business bandwidth for the access points. Access Point Mode currently supports **fixed bandwidth** billing only.

## Procedures

On the upper left corner of zenConsole, go to **Products** > **Cloud Networking** > **Cloud Router L3** > [**Create Cloud Router**](https://console.zenlayer.com/sdn/router/create).\
The overall steps of creating a cloud router is shown below. For detailed operations, please refer to the links of specific chapters.

<div align="left"><figure><img src="/files/pkCLQTFdbZbbhGOwCya2" alt="" width="482"><figcaption><p>Create a Layer 3 Cloud Router</p></figcaption></figure></div>

### 1. Select the Networking Mode

In the first step of creating a Layer 3 cloud router, select the **networking mode** for this deployment:

* **Connection Mode**: Define the interconnection between access points on demand. Recommended for networking scenarios with fewer access points.
* **Access Point Mode**: All access points in the network are automatically interconnected in a full mesh. Suitable for large-scale networking scenarios.

For the differences and full configuration steps of the two modes, see [**Networking Modes**](#networking-modes).

{% hint style="info" %} <mark style="color:blue;">**Note**</mark>

<mark style="color:blue;">The networking mode is selected at creation and cannot be changed afterward. Choose it based on your actual networking plan.</mark>
{% endhint %}

### 2. Label Your Cloud Router

Click <img src="/files/shrr5MKhrwnpdaFJ5sfQ" alt="" data-size="line"> to modify the label name of your private connect. You can also click **Add Description** to give the private connect a note.

### 3. Add Access Points

You need to add at least 2 access points and configure routing and network information to get started. By default, you can add up to 10 access points; if you need more, [**submit a support ticket**](https://console.zenlayer.com/ticket) or contact your sales representative. You will be able to make updates in the future.\
You can choose to add the following access point types:

* [**Data Center Access Type**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-a-data-center-as-access-point.md)
* [**Public Cloud Access Type**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-a-public-cloud-as-access-point.md)
* [**Bare Metal Network Access Type**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-a-vpc-as-access-point.md)
* [**Virtual Edge Access Type**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-virtual-edge-as-access-point.md)
* [**Elastic Compute Access Type**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-elastic-compute-as-access-point.md)

{% hint style="info" %} <mark style="color:blue;">**Note**</mark>

<mark style="color:blue;">You can add only one Alibaba Cloud access point into your Layer 3 cloud router temporarily.</mark>
{% endhint %}

### 4. Configure Routing

If you add access points like data centers, public clouds or virtual edges, you need to configure routing protocols to achieve network communication. If you add a VPC, go to configure access bandwidth directly.

You may have the following options, and if your device supports Border Gateway Protocol (BGP), we recommend using BGP to take care of network segment changes.

* [**BGP Routing**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-routing-information.md#bgp-routing)
* [**Static Routing**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-routing-information.md#static-routing)

{% hint style="info" %} <mark style="color:blue;">**Note**</mark>

<mark style="color:blue;">For virtual edge connection, you need to configure IPsec tunnel before configuring routing. See</mark> [<mark style="color:purple;">**IPsec Tunnel Configuration**</mark>](/welcome/cloud-networking/get-started/create-a-layer-3-connection/select-virtual-edge-as-access-point.md#ipsec-tunnel-configuration) <mark style="color:blue;">for more details.</mark>
{% endhint %}

### 5. Configure Access Bandwidth

[**Configure the access bandwidth**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-network-information.md) of each access point in your cloud router.