> 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/select-a-data-center-as-access-point.md).

# Data Center Access Type

<div align="left"><figure><img src="/files/yE21yoqyFdl7p8IuL0Dy" alt=""><figcaption><p>Data Center Connection</p></figcaption></figure></div>

When configuring a data center access point, you need to select the port to connect through and configure its routing information.

## Select Your Port

Select the port to connect through from the port list. The list includes the following information:

* **Connectivity**: The connection status of the port.
* **Label**: The name and ID of the port.
* **Used/Port speed**: The bandwidth already in use and the total bandwidth of the port.
* **Data center**: The data center where the port is located.
* **City**: The city where the port is located.

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

<mark style="color:blue;">Only</mark> <mark style="color:blue;"></mark><mark style="color:blue;">**Active**</mark> <mark style="color:blue;"></mark><mark style="color:blue;">ports with no service or with VLAN tag mode are available here. If there is no desired port, click</mark> <mark style="color:blue;"></mark><mark style="color:blue;">**Create New Port**</mark><mark style="color:blue;">.</mark>
{% endhint %}

### Create a New Port

If you do not have an existing port, or it is not your desired one, click **Create New Port**:

1. Select the port location closest to your data center.
2. Select the port specification. 1 Gbps, 10 Gbps, 100 Gbps and 400 Gbps are supported.\ <img src="/files/BWTIZWYCb7GnrFL9mThK" alt="" data-size="line"><mark style="color:blue;">**Note**</mark>\ <mark style="color:blue;">To future-proof your business, a 10 Gbps above port rate is recommended.</mark>
3. Label your port for identification.
4. Enter the legal business name of the authorized party. You will receive an LOA (letter of authorization) that is used to establish your cross connect.

   <img src="/files/BWTIZWYCb7GnrFL9mThK" alt="" data-size="line"><mark style="color:blue;">**Note**</mark>

   * <mark style="color:blue;">The LOA will be emailed to you as an attachment 2 to 3 days after you submit your new port order. You can also download your LOA in the</mark> <mark style="color:blue;">**Port**</mark> <mark style="color:blue;">on zenConsole.</mark>
   * <mark style="color:blue;">The LOA will expire in 30 days. Please establish your cross connect as soon as possible.</mark>

## Configure Routing

If your device supports Border Gateway Protocol (BGP), we recommend using **BGP** to take care of network segment changes automatically. You can also choose **Static** routing.

Configure the following routing information:

* **Customer interconnection IP**: The interconnection IP address on your side. It is recommended to use private IPs whenever possible. The customer and provider interconnection IPs should be in the same subnet, typically with a /30 mask.\
  For example: `192.168.100.1/30`.
* **Provider interconnection IP**: The interconnection IP address on the Zenlayer side.\
  For example: `192.168.100.2/30`.
* **Autonomous system number (ASN)**:
  * **Customer ASN**: Your ASN. A private ASN is recommended (16-bit: 64512–65534; 32-bit: 4200000000–4294967294).\
    For example: `65001`.
  * **Provider ASN**: The Zenlayer ASN. It defaults to `62610` and cannot be changed.
* **BGP MD5 (optional)**: The BGP authentication (message-digest algorithm 5) key. Leave it empty to disable authentication.\
  For example: `Zenlayer@2026`.

For more details about routing protocols, see [**Configure Routing**](/welcome/cloud-networking/get-started/create-a-layer-3-connection/configure-routing-information.md).

### Enable BFD

Enable Bidirectional Forwarding Detection (BFD) to quickly detect link failures and trigger failover. Once enabled, configure the following:

* **Minimum transmit interval**: In milliseconds (ms). Recommended value: `300`.
* **Minimum receive interval**: In milliseconds (ms). Recommended value: `300`.
* **Detection multiplier**: In times. Recommended value: `3` (the link is considered down after 3 consecutive detection cycles receive no packet).

### Advanced BGP Settings

Expand **Advanced BGP Settings (AS Override, Local Preference & MED)** to further optimize your routing policy:

* **Enable AS Override**: When multiple access points in your Layer 3 network use the same ASN, override the duplicate AS number in the AS path to prevent routes from being dropped by loop detection.\
  Recommendation: enable only when multiple access points share the same ASN; otherwise keep it off.
* **Configure Local Preference**: Set the local preference to control outbound traffic path selection. A higher value has higher priority.\
  For example: `100` (default); set a higher value such as `200` to prefer a specific link.
* **Configure MED**: Set the Multi-Exit Discriminator (MED) to influence inbound traffic path selection. A lower value has higher priority.\
  For example: `0` (default); set a lower value to prefer a specific link.

Once configured, click **Save** to save the configuration of this access point.