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docs/architecture.md

@@ -37,7 +37,7 @@ microsoft) and other services use OIDC.
 X.509 user-certificates may also be used at different places, but there is
 a general trend to deprecate them (for user authentication).
 
-![NFDI AAI Architecture v2.5](images/nfdi-aai-options-v2.5-glow.png){: style="width:700px"}
+![Hierarchical view of the NFDI architecture diagram that follows the AARC Blueprint Architecture. eduGAIN and other IdPs are in the identity layer on top, followed by the Edu-ID proxy and then by the Community AAI proxies. The Community AAI proxies can connect to community services. The bottom layer shows the NFDI infrastructure proxy which connects to multiple Community AAI proxies and targets NFDI infrastructure services which are relevant for multiple communities.  ](images/nfdi-aai-options-v2.5-glow.png "NFDI AAI Architecture v2.5"){: style="width:700px"}
 
 !!! info