Update faq.md

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@@ -400,3 +400,6 @@ I guess my question is more specifically: “Will the compliance checker look at
 
 *Question*: <a name="setup_keruntime"></a> There is an existing Knowledge Network with a Knowledge Directory (KD) and multiple Knowledge Engine Runtimes (KERs). How do I setup my own KER and configure it such that it participates in the existing Knowledge Network?
 - *Answer*: Every Knowledge Engine Runtime (KER) in distributed mode consists of two APIs: [Knowledge Engine Developer REST API](https://github.com/TNO/knowledge-engine/blob/1.2.5/smart-connector-rest-server/src/main/resources/openapi-sc.yaml) and the [Inter-Knowledge Engine Runtime API](https://github.com/TNO/knowledge-engine/blob/1.2.5/smart-connector/src/main/resources/openapi-inter-ker.yaml). The former is started on port `8280` by default and you use this API to register your Knowledge Base and Knowledge Interactions. The latter API is meant for internal communication between KERs and you do not need to use it yourself. However, you do need to make sure this API is reachable for other KERs in the Knowledge Network. By default this API is available on port 8081, but sometimes you need to change this port using the `KE_RUNTIME_PORT` environment variable. Make sure the latter API of your KER is accessible from the internet and configure its URL when starting the KER with the `KE_RUNTIME_EXPOSED_URL` environment variable. To set this up correctly, you typically install a reverse proxy like NGNIX and open the correct ports in the firewall of the server. For this you need to contact the administrator of the server you are using. A KER starts in distributed mode when it detects the `KD_URL` environment variable. This variable points to the Knowledge Directory of the Knowledge Network. You can configure it using environment variables `KD_URL=<knowledge-direcotry-url>`. If the Knowledge Directory is protected using Basic Authentication, you can add the credentials to the KD_URL as described [here](https://stackoverflow.com/a/50528734).
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+*Question*: <a name="connect_keruntime"> There is an existing Knowledge Engine Runtime (KER) that I want to use to develop a knowledge base. How do I connect to this KER?
+- *Answer*: To connect to the existing KER you need to know and have access to the KER's [Knowledge Engine REST Developer API](https://github.com/TNO/knowledge-engine/blob/1.2.5/smart-connector-rest-server/src/main/resources/openapi-sc.yaml). If you have the URL of the KER you want to use, you can test it by activating its `GET /sc` operation via the browser with an URL that looks like this: `<ker-url>/sc` (if the KER is protected with Basic Authentication your browser might ask you for credentials, you can also put the credentials directly into the URL as user info). This operation returns JSON with all the Knowledge Bases (KBs) that are registered with that KER (if there are none, it returns an empty JSON array `[]`). If you run a KER on your own computer (for example using the provided docker image), the `<ker-url>` would typically be `http://localhost:8280`. Now that you tested the KER, you can use the `<ker-url>` to register your KB and Knowledge Interactions (KIs) by activating the different operations that are described in the Open API specification above.