How User Request Flow In Citrix

How User Request Flow In Citrix

In this Blog i will try to explain about complete user request flow with in Citrix XenDesktop environment. Please see Below how request flow and make this self explanatory i gave numbers in design document,

1. At first user open browser and put his credentials at netscaler or store front or Webinterface. If netscaler is only configured as gateway then it pass the credentials to store front other wise do authentication by it's own. (For more details on configuration part i request to visit "http://rajatcitrix.blogspot.in/2015/07/citrix-netscaler-105-learn-in-one-day.html")
2. Store front verify credentials from Domain Controller and pass the validation to Delivery controller.

3. Delivery controller generates STA and it's broker service query database for list of authorized resources. 

4. Resource information passed back to Storefront and from there to end user's desktop.

5. User clicks on one of the resource icons to start a desktop or application session. Same information has been passed back to Delivery controller.

6. Delivery controller provide information about available resource  Delivery Group obtained from the available resource information from Hypervisor within that delivery group.
6. Delivery Controller identifies to Web Interface/StoreFront the virtual machine it assigned for this particular session.
7. Web Interface/StoreFront creates and sends an ICA file to the Netscaler with STA pointing to the virtual machine that hypervisor identified. STA validation happens at netscaler.
8. Citrix Receiver establishes an ICA connection to the specific virtual machine through netscaler that the DDC allocated for this session.
9. Virtual Delivery Agent (VDA) verifies the license file with the DDC.
10. DDC queries Citrix License server to verify that the end user has a valid ticket.
11. DDC passes session policies to the VDA, which then applies session policies to the virtual machine.
12. Citrix Receiver displays the selected resource to the end user.
13. Administrator and help desk personnel use Desktop Director and Desktop Studio tools to manage the desktops from the management server.

<<VISIO diagram is in progress>>

Quick Reference:

Desktop Receiver >> Firewall >> Storefront >>  Query AD through Broker Service >> Contact Delivery controller >> Generate STA >> XML service contact SiteDB for list of authorized resource >> Information goes back to storefront via DC >> User Click on resource  >> Request goes to DC >> XML service contact site DB for available resource info >> Information goes back to Storefront for ICA file creation STA >> File goes to netscaler for STA verification >> ICA hand shake start and licence validation  happen >> Application successfully be launched to user desktop.

Thanks for reading the Blog! Feel free to comment in case i missed something or i am wrong somewhere.