---
title: kIOPropertyPortTopologyKey
framework: DriverKit
role: symbol
role_heading: Macro
platforms: [DriverKit 20.0+, macOS 10.3+]
path: kernel/kiopropertyporttopologykey
---

# kIOPropertyPortTopologyKey

## Declaration

```occ
#define kIOPropertyPortTopologyKey
```

## Discussion

This key is associated with the current port topology. The port topology can be any valid topology for the interconnect.

Note: This value can change. It is not a static value.

Requirement: Optional for any interconnect.

Example:

```occ
 
 
<dict>
   <key>Controller Characteristics</key>
   <dict>
   	<key>Port Topology</key>
   	<string>Automatic (N_Port)</string>
   </dict>
</dict>
```