User guide

© 2011 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information. Cisco Validated Design Page 21
Figure 19. Operational Sequence
1. The end user launches an internet browser to access Web Interface.
2. Web Interfaces prompts the user for Active Directory credentials and passes the credentials to the
Desktop Delivery Controller acting as a dedicated XML server.
3. The XML Service running the dedicated XML server (Desktop Delivery Controller) authenticates the user
against Active Directory.
4. After the user is successfully authenticated, the XML Service contacts the Data Store to determine which
virtual desktops are available for that user.
5. The virtual desktop information is sent back to Web Interface and Web Interface renders a web page
containing a list of available desktops.
6. The user clicks on the desktop icon and Web Interface forwards the request to the Desktop Delivery
Controller. If the virtual desktop is powered on, the Desktop Delivery Controller will tell the Virtual Desktop
Agent running on the virtual machine to start listening for an incoming session. If the virtual desktop is not
powered on, the Desktop Delivery Controller will tell the XenServer to start a new virtual desktop and then
notify the Virtual Desktop Agent.
a. In a Hosted VDI configuration with Provisioning Services, the virtual desktop boots through the
network PXE boot. The virtual desktop contacts the DHCP server to find an IP address and the
location of the boot file. The boot file comes from Provisioning Services and provides instructions
for accessing the centralized desktop image.
b. After the virtual desktop receives the boot file with instructions, it contacts the Provisioning Server
and provides its MAC address. Provisioning Server identifies the correct virtual desktop disk
based on the MAC address and sends portions of the virtual disk to the virtual desktop required to
start-up the machine.
7. The virtual desktop connection information is forwarded onto Web Interface. Web Interface creates a
launch file (ICA) for the specific virtual desktop and forwards the launch file to the end user‘s device.
8. The Virtual Desktop Agent running on the virtual desktop tells the Desktop Delivery Controller that the
user has connected. The user‘s logon information is then sent for validation.