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This configuration can be used to set up a CORD development environment.
It does the following:
-* Configures XOS with the CORD services: vCPE, vBNG, vOLT
-* Brings up ONOS apps for controlling the dataplane: virtualbng, olt
* Sets up a basic dataplane for testing end-to-end packet flow between a subscriber client and the Internet
+* Brings up ONOS apps for controlling the dataplane: virtualbng, olt
+* Configures XOS with the CORD services: vCPE, vBNG, vOLT
**NOTE:** This configuration is under **active development** and is not yet finished! Some features are not
fully working yet.
+## End-to-end dataplane
+
+The configuration uses XOS to set up an end-to-end dataplane for development of the XOS services and ONOS apps
+used in CORD. It abstracts away most of the complexity of the CORD hardware using virtual networks
+and Open vSwitch (OvS) switches. At a high level the dataplane looks like this:
+
+```
+ olt virtualbng
+ ---- ----
+ ONOS ONOS
+ | |
+client ----> OvS ----> vCPE ----> OvS ----> Internet
+ 1 2 3 4
+```
+
+On the datapath are two OvS switches, controlled by the `olt` and `virtualbng` ONOS applications. Once all the pieces are in
+place, the client at left should be able to obtain an IP address via DHCP from the vCPE and send packets out to the Internet.
+
+All of the components in the above diagram (i.e., client, OvS switches, ONOS, and vCPE) currently run in distinct VMs
+created by XOS. The numbers in the diagram correspond to networks set up by XOS:
+
+1. subscriber_network
+2. lan_network
+3. wan_network
+4. public_network
+
## How to run it
The configuration is intended to be run on [CloudLab](http://cloudlab.us), on the *ctl* node set up by the OpenStack profile.