diff --git a/Docs/General Architecture.md b/Docs/General Architecture.md
index c25c052..ca3a70d 100644
--- a/Docs/General Architecture.md	
+++ b/Docs/General Architecture.md	
@@ -107,12 +107,15 @@ queue       "EgwDoor Proc" AS B.4
 
 ## (B.2) Redis Server
 
+The REDIS server vill act as a cache / high speed data layer for example for managing multiple session with the cluster of WebDoor Instances and, at the same time, to act as a inter-process channel manager to permit data exchange between each solution component.
 
-<div style="page-break-after: always; visibility: hidden"></div>
+It is a RAM based server and must be kept secure in the "green zone" of the customer IT datacenter. 
 
 
 ## (B.3) Main DB
 
+The Main DB server will be, as a first choice (and if not otherwise requested by customer) a Microsoft SqlServer Express instance. Can be swapped for a MariaDB (MySQL) solution, in particular in case ofcluster DB requirements (high availability and if concurrent data access requirements exceed SqlServer capacity), but at the moment we expect MS SqlServer is the best fit.
+
 <div style="page-break-after: always; visibility: hidden"></div>
 
 ## (B.4) EgwDoor Processor
diff --git a/Docs/General Architecture.pdf b/Docs/General Architecture.pdf
index 49ba8ad..4848cb2 100644
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