answer to questions for self-checking
Change-Id: I9fab290e7ff3417e6523596d3df00dd757132ded
diff --git a/apps/p4-tutorial/README.md b/apps/p4-tutorial/README.md
index 9373890..17f6711 100644
--- a/apps/p4-tutorial/README.md
+++ b/apps/p4-tutorial/README.md
@@ -59,6 +59,8 @@
* What happens if a matching entry is not found in table `t_l2_fwd`? What's the
next table applied to the packet?
+[Click here to see the solution to these questions](./questions.md)
+
### MyTunnel Pipeconf
The `mytunnel.p4` program is provided to ONOS as part of a "pipeconf".
diff --git a/apps/p4-tutorial/exercise-2.md b/apps/p4-tutorial/exercise-2.md
index a2a4b1c..2c48a1f 100644
--- a/apps/p4-tutorial/exercise-2.md
+++ b/apps/p4-tutorial/exercise-2.md
@@ -130,7 +130,7 @@
$ onos localhost
```
- 2. **Acticate the BMv2 drivers, pipeconf, and MyTunnel app**:
+ 2. **Activate the BMv2 drivers, pipeconf, and MyTunnel app**:
```
onos> app activate org.onosproject.drivers.bmv2
diff --git a/apps/p4-tutorial/questions.md b/apps/p4-tutorial/questions.md
new file mode 100644
index 0000000..3c427ba
--- /dev/null
+++ b/apps/p4-tutorial/questions.md
@@ -0,0 +1,28 @@
+Here is an answer to the questions that you can compare with your own.
+
+* **Which protocol headers are being extracted from each packet?**
+ There are three headers defined for packets from the controlplane (ethernet_t, my_tunnel_t and ipv4_t) and two headers for packets from/to controller (packet_out_header_t and packet_in_header_t ).
+
+* **How can the parser distinguish a packet with MyTunnel encapsulation from one without?**
+ This is done checking the value of the ether_type field. If ETH_TYPE_MYTUNNEL = 0x1212 this is a packet with MyTunnel encapsulation.
+
+* **How many match+action tables are defined in the P4 program?**
+ There are three tables defined: t_l2_fwd, t_tunnel_ingress and t_tunnel_fwd.
+
+* **What is the first table in the pipeline applied to every packet?**
+ The first table in the pipeline is t_l2_fwd.
+
+* **Which headers can be matched on table t_l2_fwd?**
+ hdr.ethernet.dst_addr, hdr.ethernet.src_addr, and hdr.ethernet.ether_type.
+
+* **Which type of match is applied to t_l2_fwd? E.g. exact match, ternary, or longest-prefix match?**
+ Ternary.
+
+* **Which actions can be executed on matched packets?**
+ set_out_port, send_to_cpu, _drop, NoAction.
+
+* **Which action can be used to send a packet to the controller?**
+ action send_to_cpu()
+
+* **What happens if a matching entry is not found in table t_l2_fwd? What's the next table applied to the packet?**
+ If a matching entry is not found in table t_l2_fwd the next table applied is t_tunnel_ingress to process only non-tunneled IPv4 packets or t_tunnel_fwd for tunneled packets.