Final edits for SIGCOMM tutorial (#191)
* Final updates for SIGCOMM '18 * Final updates for SIGCOMM '18
This commit is contained in:
Nate Foster
committed by
Robert Soule
Robert Soule
parent
6ccdbc34bd
commit
763b95a880
@@ -1,5 +0,0 @@
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BMV2_SWITCH_EXE = simple_switch_grpc
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NO_P4 = true
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P4C_ARGS = --p4runtime-file $(basename $@).p4info --p4runtime-format text
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include ../../utils/Makefile
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Before Width: | Height: | Size: 154 B |
@@ -1,198 +0,0 @@
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# Implementing ECN
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## Introduction
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The objective of this tutorial is to extend basic L3 forwarding with
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an implementation of Explicit Congestion Notification (ECN).
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ECN allows end-to-end notification of network congestion without
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dropping packets. If an end-host supports ECN, it puts the value of 1
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or 2 in the `ipv4.ecn` field. For such packets, each switch may
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change the value to 3 if the queue size is larger than a threshold.
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The receiver copies the value to sender, and the sender can lower the
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rate.
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As before, we have already defined the control plane rules for
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routing, so you only need to implement the data plane logic of your P4
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program.
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> **Spoiler alert:** There is a reference solution in the `solution`
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> sub-directory. Feel free to compare your implementation to the reference.
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## Step 1: Run the (incomplete) starter code
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The directory with this README also contains a skeleton P4 program,
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`ecn.p4`, which initially implements L3 forwarding. Your job (in the
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next step) will be to extend it to properly append set the ECN bits
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Before that, let's compile the incomplete `ecn.p4` and bring up a
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network in Mininet to test its behavior.
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1. In your shell, run:
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```bash
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make
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```
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This will:
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* compile `ecn.p4`, and
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* start a Mininet instance with three switches (`s1`, `s2`, `s3`) configured
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in a triangle. There are 5 hosts. `h1` and `h11` are connected to `s1`.
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`h2` and `h22` are connected to `s2` and `h3` is connected to `s3`.
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* The hosts are assigned IPs of `10.0.1.1`, `10.0.2.2`, etc
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(`10.0.<Switchid>.<hostID>`).
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* The control plane programs the P4 tables in each switch based on
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`sx-runtime.json`
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2. We want to send a low rate traffic from `h1` to `h2` and a high
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rate iperf traffic from `h11` to `h22`. The link between `s1` and
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`s2` is common between the flows and is a bottleneck because we
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reduced its bandwidth to 512kbps in topology.json. Therefore, if we
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capture packets at `h2`, we should see the right ECN value.
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3. You should now see a Mininet command prompt. Open four terminals
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for `h1`, `h11`, `h2`, `h22`, respectively:
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```bash
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mininet> xterm h1 h11 h2 h22
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```
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3. In `h2`'s XTerm, start the server that captures packets:
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```bash
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./receive.py
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```
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4. in `h22`'s XTerm, start the iperf UDP server:
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```bash
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iperf -s -u
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```
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5. In `h1`'s XTerm, send one packet per second to `h2` using send.py
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say for 30 seconds:
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```bash
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./send.py 10.0.2.2 "P4 is cool" 30
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```
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The message "P4 is cool" should be received in `h2`'s xterm,
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6. In `h11`'s XTerm, start iperf client sending for 15 seconds
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```bash
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iperf -c 10.0.2.22 -t 15 -u
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```
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7. At `h2`, the `ipv4.tos` field (DiffServ+ECN) is always 1
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8. type `exit` to close each XTerm window
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Your job is to extend the code in `ecn.p4` to implement the ECN logic
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for setting the ECN flag.
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## Step 2: Implement ECN
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The `ecn.p4` file contains a skeleton P4 program with key pieces of
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logic replaced by `TODO` comments. These should guide your
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implementation---replace each `TODO` with logic implementing the
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missing piece.
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First we have to change the ipv4_t header by splitting the TOS field
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into DiffServ and ECN fields. Remember to update the checksum block
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accordingly. Then, in the egress control block we must compare the
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queue length with ECN_THRESHOLD. If the queue length is larger than
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the threshold, the ECN flag will be set. Note that this logic should
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happen only if the end-host declared supporting ECN by setting the
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original ECN to 1 or 2.
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A complete `ecn.p4` will contain the following components:
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1. Header type definitions for Ethernet (`ethernet_t`) and IPv4 (`ipv4_t`).
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2. Parsers for Ethernet, IPv4,
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3. An action to drop a packet, using `mark_to_drop()`.
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4. An action (called `ipv4_forward`), which will:
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1. Set the egress port for the next hop.
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2. Update the ethernet destination address with the address of
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the next hop.
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3. Update the ethernet source address with the address of the switch.
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4. Decrement the TTL.
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5. An egress control block that checks the ECN and
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`standard_metadata.enq_qdepth` and sets the ipv4.ecn.
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6. A deparser that selects the order in which fields inserted into the outgoing
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packet.
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7. A `package` instantiation supplied with the parser, control,
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checksum verification and recomputation and deparser.
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## Step 3: Run your solution
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Follow the instructions from Step 1. This time, when your message from
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`h1` is delivered to `h2`, you should see `tos` values change from 1
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to 3 as the queue builds up. `tos` may change back to 1 when iperf
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finishes and the queue depletes.
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To easily track the `tos` values you may want to redirect the output
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of `h2` to a file by running the following for `h2`
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```bash
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./receive.py > h2.log
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```
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and just print the `tos` values `grep tos h2.log` in a separate window
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```
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x3
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tos = 0x3
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tos = 0x3
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tos = 0x3
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tos = 0x3
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tos = 0x3
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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tos = 0x1
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```
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### Food for thought
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How can we let the user configure the threshold?
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### Troubleshooting
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There are several ways that problems might manifest:
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1. `ecn.p4` fails to compile. In this case, `make` will report the
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error emitted from the compiler and stop.
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2. `ecn.p4` compiles but does not support the control plane rules in
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the `sX-runtime.json` files that `make` tries to install using
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a Python controller. In this case, `make` will log the controller output
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in the `logs` directory. Use these error messages to fix your `ecn.p4`
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implementation.
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3. `ecn.p4` compiles, and the control plane rules are installed, but
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the switch does not process packets in the desired way. The
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`/tmp/p4s.<switch-name>.log` files contain trace messages
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describing how each switch processes each packet. The output is
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detailed and can help pinpoint logic errors in your implementation.
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The `build/<switch-name>-<interface-name>.pcap` also contains the
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pcap of packets on each interface. Use `tcpdump -r <filename> -xxx`
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to print the hexdump of the packets.
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4. `ecn.p4` compiles and all rules are installed. Packets go through
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and the logs show that the queue length was not high enough to set
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the ECN bit. Then either lower the threshold in the p4 code or
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reduce the link bandwidth in `topology.json`
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#### Cleaning up Mininet
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In the latter two cases above, `make` may leave a Mininet instance
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running in the background. Use the following command to clean up
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these instances:
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```bash
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make stop
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```
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## Next Steps
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Congratulations, your implementation works! Move on to the next
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exercise: [Multi-Hop Route Inspection](../mri), which identifies which
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link is the source of congestion.
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@@ -1,187 +0,0 @@
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/* -*- P4_16 -*- */
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#include <core.p4>
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#include <v1model.p4>
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const bit<8> TCP_PROTOCOL = 0x06;
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const bit<16> TYPE_IPV4 = 0x800;
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const bit<19> ECN_THRESHOLD = 10;
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/*************************************************************************
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*********************** H E A D E R S ***********************************
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*************************************************************************/
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typedef bit<9> egressSpec_t;
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typedef bit<48> macAddr_t;
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typedef bit<32> ip4Addr_t;
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header ethernet_t {
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macAddr_t dstAddr;
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macAddr_t srcAddr;
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bit<16> etherType;
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}
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/*
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* TODO: split tos to two fields 6 bit diffserv and 2 bit ecn
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*/
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header ipv4_t {
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bit<4> version;
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bit<4> ihl;
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bit<8> tos;
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bit<16> totalLen;
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bit<16> identification;
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bit<3> flags;
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bit<13> fragOffset;
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bit<8> ttl;
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bit<8> protocol;
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bit<16> hdrChecksum;
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ip4Addr_t srcAddr;
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ip4Addr_t dstAddr;
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}
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struct metadata {
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}
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struct headers {
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ethernet_t ethernet;
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ipv4_t ipv4;
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}
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/*************************************************************************
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*********************** P A R S E R ***********************************
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*************************************************************************/
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parser MyParser(packet_in packet,
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out headers hdr,
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inout metadata meta,
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inout standard_metadata_t standard_metadata) {
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state start {
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transition parse_ethernet;
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}
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state parse_ethernet {
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packet.extract(hdr.ethernet);
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transition select(hdr.ethernet.etherType) {
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TYPE_IPV4: parse_ipv4;
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default: accept;
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}
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}
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state parse_ipv4 {
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packet.extract(hdr.ipv4);
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transition accept;
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}
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}
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/*************************************************************************
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************ C H E C K S U M V E R I F I C A T I O N *************
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*************************************************************************/
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control MyVerifyChecksum(inout headers hdr, inout metadata meta) {
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apply { }
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}
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/*************************************************************************
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************** I N G R E S S P R O C E S S I N G *******************
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*************************************************************************/
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control MyIngress(inout headers hdr,
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inout metadata meta,
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inout standard_metadata_t standard_metadata) {
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action drop() {
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mark_to_drop();
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}
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action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) {
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standard_metadata.egress_spec = port;
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hdr.ethernet.srcAddr = hdr.ethernet.dstAddr;
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hdr.ethernet.dstAddr = dstAddr;
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hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
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}
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table ipv4_lpm {
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key = {
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hdr.ipv4.dstAddr: lpm;
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}
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actions = {
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ipv4_forward;
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drop;
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}
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size = 1024;
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default_action = drop;
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}
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apply {
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if (hdr.ipv4.isValid()) {
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ipv4_lpm.apply();
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}
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}
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}
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/*************************************************************************
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**************** E G R E S S P R O C E S S I N G *******************
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*************************************************************************/
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control MyEgress(inout headers hdr,
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inout metadata meta,
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inout standard_metadata_t standard_metadata) {
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apply {
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/*
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* TODO:
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* - if ecn is 1 or 2
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* - compare standard_metadata.enq_qdepth with threshold
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* and set hdr.ipv4.ecn to 3 if larger
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*/
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}
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}
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/*************************************************************************
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************* C H E C K S U M C O M P U T A T I O N **************
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*************************************************************************/
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control MyComputeChecksum(inout headers hdr, inout metadata meta) {
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apply {
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/* TODO: replace tos with diffserve and ecn */
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update_checksum(
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hdr.ipv4.isValid(),
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{ hdr.ipv4.version,
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hdr.ipv4.ihl,
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hdr.ipv4.tos,
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hdr.ipv4.totalLen,
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hdr.ipv4.identification,
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hdr.ipv4.flags,
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hdr.ipv4.fragOffset,
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hdr.ipv4.ttl,
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hdr.ipv4.protocol,
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hdr.ipv4.srcAddr,
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hdr.ipv4.dstAddr },
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hdr.ipv4.hdrChecksum,
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HashAlgorithm.csum16);
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}
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}
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/*************************************************************************
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*********************** D E P A R S E R *******************************
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*************************************************************************/
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control MyDeparser(packet_out packet, in headers hdr) {
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apply {
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packet.emit(hdr.ethernet);
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packet.emit(hdr.ipv4);
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}
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}
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/*************************************************************************
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*********************** S W I T C H *******************************
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*************************************************************************/
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V1Switch(
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MyParser(),
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MyVerifyChecksum(),
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MyIngress(),
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MyEgress(),
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MyComputeChecksum(),
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MyDeparser()
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) main;
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@@ -1,37 +0,0 @@
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#!/usr/bin/env python
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import sys
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import struct
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from scapy.all import sniff, sendp, hexdump, get_if_list, get_if_hwaddr
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from scapy.all import Packet
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from scapy.all import IP, UDP, Raw
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from scapy.layers.inet import _IPOption_HDR
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def get_if():
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ifs=get_if_list()
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iface=None
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for i in get_if_list():
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if "eth0" in i:
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iface=i
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break;
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if not iface:
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print "Cannot find eth0 interface"
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exit(1)
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return iface
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def handle_pkt(pkt):
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print "got a packet"
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pkt.show2()
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# hexdump(pkt)
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sys.stdout.flush()
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def main():
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iface = 'h2-eth0'
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print "sniffing on %s" % iface
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sys.stdout.flush()
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sniff(filter="udp and port 4321", iface = iface,
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prn = lambda x: handle_pkt(x))
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if __name__ == '__main__':
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main()
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@@ -1,52 +0,0 @@
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{
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"target": "bmv2",
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"p4info": "build/ecn.p4info",
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"bmv2_json": "build/ecn.json",
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"table_entries": [
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{
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"table": "MyIngress.ipv4_lpm",
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"match": {
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"hdr.ipv4.dstAddr": ["10.0.1.1", 32]
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},
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"action_name": "MyIngress.ipv4_forward",
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"action_params": {
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"dstAddr": "00:00:00:00:01:01",
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"port": 2
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}
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},
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{
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"table": "MyIngress.ipv4_lpm",
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"match": {
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"hdr.ipv4.dstAddr": ["10.0.1.11", 32]
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},
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"action_name": "MyIngress.ipv4_forward",
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"action_params": {
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"dstAddr": "00:00:00:00:01:0b",
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"port": 1
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}
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},
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{
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"table": "MyIngress.ipv4_lpm",
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"match": {
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"hdr.ipv4.dstAddr": ["10.0.2.0", 24]
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},
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"action_name": "MyIngress.ipv4_forward",
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"action_params": {
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"dstAddr": "00:00:00:02:03:00",
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"port": 3
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}
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},
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{
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"table": "MyIngress.ipv4_lpm",
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"match": {
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"hdr.ipv4.dstAddr": ["10.0.3.0", 24]
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},
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"action_name": "MyIngress.ipv4_forward",
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"action_params": {
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"dstAddr": "00:00:00:03:02:00",
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"port": 4
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}
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}
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]
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}
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@@ -1,51 +0,0 @@
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{
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"target": "bmv2",
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"p4info": "build/ecn.p4info",
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"bmv2_json": "build/ecn.json",
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"table_entries": [
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{
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"table": "MyIngress.ipv4_lpm",
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"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.2.2", 32]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:00:02:02",
|
||||
"port": 2
|
||||
}
|
||||
},
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.2.22", 32]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:00:02:16",
|
||||
"port": 1
|
||||
}
|
||||
},
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.1.0", 24]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:01:03:00",
|
||||
"port": 3
|
||||
}
|
||||
},
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.3.0", 24]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:03:03:00",
|
||||
"port": 4
|
||||
}
|
||||
}
|
||||
]
|
||||
}
|
||||
@@ -1,40 +0,0 @@
|
||||
{
|
||||
"target": "bmv2",
|
||||
"p4info": "build/ecn.p4info",
|
||||
"bmv2_json": "build/ecn.json",
|
||||
"table_entries": [
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.3.3", 32]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:00:03:03",
|
||||
"port": 1
|
||||
}
|
||||
},
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.1.0", 24]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:01:04:00",
|
||||
"port": 2
|
||||
}
|
||||
},
|
||||
{
|
||||
"table": "MyIngress.ipv4_lpm",
|
||||
"match": {
|
||||
"hdr.ipv4.dstAddr": ["10.0.2.0", 24]
|
||||
},
|
||||
"action_name": "MyIngress.ipv4_forward",
|
||||
"action_params": {
|
||||
"dstAddr": "00:00:00:02:04:00",
|
||||
"port": 3
|
||||
}
|
||||
}
|
||||
]
|
||||
}
|
||||
@@ -1,50 +0,0 @@
|
||||
#!/usr/bin/env python
|
||||
|
||||
import argparse
|
||||
import sys
|
||||
import socket
|
||||
import random
|
||||
import struct
|
||||
|
||||
from scapy.all import sendp, send, hexdump, get_if_list, get_if_hwaddr
|
||||
from scapy.all import Packet, IPOption
|
||||
from scapy.all import Ether, IP, UDP
|
||||
from scapy.all import IntField, FieldListField, FieldLenField, ShortField
|
||||
from scapy.layers.inet import _IPOption_HDR
|
||||
|
||||
from time import sleep
|
||||
|
||||
def get_if():
|
||||
ifs=get_if_list()
|
||||
iface=None # "h1-eth0"
|
||||
for i in get_if_list():
|
||||
if "eth0" in i:
|
||||
iface=i
|
||||
break;
|
||||
if not iface:
|
||||
print "Cannot find eth0 interface"
|
||||
exit(1)
|
||||
return iface
|
||||
|
||||
def main():
|
||||
|
||||
if len(sys.argv)<4:
|
||||
print 'pass 2 arguments: <destination> "<message>" <duration>'
|
||||
exit(1)
|
||||
|
||||
addr = socket.gethostbyname(sys.argv[1])
|
||||
iface = get_if()
|
||||
|
||||
pkt = Ether(src=get_if_hwaddr(iface), dst="ff:ff:ff:ff:ff:ff") / IP(dst=addr, tos=1) / UDP(dport=4321, sport=1234) / sys.argv[2]
|
||||
pkt.show2()
|
||||
#hexdump(pkt)
|
||||
try:
|
||||
for i in range(int(sys.argv[3])):
|
||||
sendp(pkt, iface=iface)
|
||||
sleep(1)
|
||||
except KeyboardInterrupt:
|
||||
raise
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
main()
|
||||
Binary file not shown.
|
Before Width: | Height: | Size: 221 KiB |
@@ -1,188 +0,0 @@
|
||||
/* -*- P4_16 -*- */
|
||||
#include <core.p4>
|
||||
#include <v1model.p4>
|
||||
|
||||
const bit<8> TCP_PROTOCOL = 0x06;
|
||||
const bit<16> TYPE_IPV4 = 0x800;
|
||||
const bit<19> ECN_THRESHOLD = 10;
|
||||
|
||||
/*************************************************************************
|
||||
*********************** H E A D E R S ***********************************
|
||||
*************************************************************************/
|
||||
|
||||
typedef bit<9> egressSpec_t;
|
||||
typedef bit<48> macAddr_t;
|
||||
typedef bit<32> ip4Addr_t;
|
||||
|
||||
header ethernet_t {
|
||||
macAddr_t dstAddr;
|
||||
macAddr_t srcAddr;
|
||||
bit<16> etherType;
|
||||
}
|
||||
|
||||
header ipv4_t {
|
||||
bit<4> version;
|
||||
bit<4> ihl;
|
||||
bit<6> diffserv;
|
||||
bit<2> ecn;
|
||||
bit<16> totalLen;
|
||||
bit<16> identification;
|
||||
bit<3> flags;
|
||||
bit<13> fragOffset;
|
||||
bit<8> ttl;
|
||||
bit<8> protocol;
|
||||
bit<16> hdrChecksum;
|
||||
ip4Addr_t srcAddr;
|
||||
ip4Addr_t dstAddr;
|
||||
}
|
||||
|
||||
struct metadata {
|
||||
}
|
||||
|
||||
struct headers {
|
||||
ethernet_t ethernet;
|
||||
ipv4_t ipv4;
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
*********************** P A R S E R ***********************************
|
||||
*************************************************************************/
|
||||
|
||||
parser MyParser(packet_in packet,
|
||||
out headers hdr,
|
||||
inout metadata meta,
|
||||
inout standard_metadata_t standard_metadata) {
|
||||
|
||||
state start {
|
||||
transition parse_ethernet;
|
||||
}
|
||||
|
||||
state parse_ethernet {
|
||||
packet.extract(hdr.ethernet);
|
||||
transition select(hdr.ethernet.etherType) {
|
||||
TYPE_IPV4: parse_ipv4;
|
||||
default: accept;
|
||||
}
|
||||
}
|
||||
|
||||
state parse_ipv4 {
|
||||
packet.extract(hdr.ipv4);
|
||||
transition accept;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/*************************************************************************
|
||||
************ C H E C K S U M V E R I F I C A T I O N *************
|
||||
*************************************************************************/
|
||||
|
||||
control MyVerifyChecksum(inout headers hdr, inout metadata meta) {
|
||||
apply { }
|
||||
}
|
||||
|
||||
|
||||
/*************************************************************************
|
||||
************** I N G R E S S P R O C E S S I N G *******************
|
||||
*************************************************************************/
|
||||
|
||||
control MyIngress(inout headers hdr,
|
||||
inout metadata meta,
|
||||
inout standard_metadata_t standard_metadata) {
|
||||
action drop() {
|
||||
mark_to_drop();
|
||||
}
|
||||
|
||||
action ipv4_forward(macAddr_t dstAddr, egressSpec_t port) {
|
||||
standard_metadata.egress_spec = port;
|
||||
hdr.ethernet.srcAddr = hdr.ethernet.dstAddr;
|
||||
hdr.ethernet.dstAddr = dstAddr;
|
||||
hdr.ipv4.ttl = hdr.ipv4.ttl - 1;
|
||||
}
|
||||
|
||||
table ipv4_lpm {
|
||||
key = {
|
||||
hdr.ipv4.dstAddr: lpm;
|
||||
}
|
||||
actions = {
|
||||
ipv4_forward;
|
||||
drop;
|
||||
NoAction;
|
||||
}
|
||||
size = 1024;
|
||||
default_action = NoAction();
|
||||
}
|
||||
|
||||
apply {
|
||||
if (hdr.ipv4.isValid()) {
|
||||
ipv4_lpm.apply();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
**************** E G R E S S P R O C E S S I N G *******************
|
||||
*************************************************************************/
|
||||
|
||||
control MyEgress(inout headers hdr,
|
||||
inout metadata meta,
|
||||
inout standard_metadata_t standard_metadata) {
|
||||
action mark_ecn() {
|
||||
hdr.ipv4.ecn = 3;
|
||||
}
|
||||
apply {
|
||||
if (hdr.ipv4.ecn == 1 || hdr.ipv4.ecn == 2){
|
||||
if (standard_metadata.enq_qdepth >= ECN_THRESHOLD){
|
||||
mark_ecn();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
************* C H E C K S U M C O M P U T A T I O N **************
|
||||
*************************************************************************/
|
||||
|
||||
control MyComputeChecksum(inout headers hdr, inout metadata meta) {
|
||||
apply {
|
||||
update_checksum(
|
||||
hdr.ipv4.isValid(),
|
||||
{ hdr.ipv4.version,
|
||||
hdr.ipv4.ihl,
|
||||
hdr.ipv4.diffserv,
|
||||
hdr.ipv4.ecn,
|
||||
hdr.ipv4.totalLen,
|
||||
hdr.ipv4.identification,
|
||||
hdr.ipv4.flags,
|
||||
hdr.ipv4.fragOffset,
|
||||
hdr.ipv4.ttl,
|
||||
hdr.ipv4.protocol,
|
||||
hdr.ipv4.srcAddr,
|
||||
hdr.ipv4.dstAddr },
|
||||
hdr.ipv4.hdrChecksum,
|
||||
HashAlgorithm.csum16);
|
||||
}
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
*********************** D E P A R S E R *******************************
|
||||
*************************************************************************/
|
||||
|
||||
control MyDeparser(packet_out packet, in headers hdr) {
|
||||
apply {
|
||||
packet.emit(hdr.ethernet);
|
||||
packet.emit(hdr.ipv4);
|
||||
}
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
*********************** S W I T C H *******************************
|
||||
*************************************************************************/
|
||||
|
||||
V1Switch(
|
||||
MyParser(),
|
||||
MyVerifyChecksum(),
|
||||
MyIngress(),
|
||||
MyEgress(),
|
||||
MyComputeChecksum(),
|
||||
MyDeparser()
|
||||
) main;
|
||||
@@ -1,18 +0,0 @@
|
||||
{
|
||||
"hosts": [
|
||||
"h1",
|
||||
"h2",
|
||||
"h3",
|
||||
"h11",
|
||||
"h22"
|
||||
],
|
||||
"switches": {
|
||||
"s1": { "runtime_json" : "s1-runtime.json" },
|
||||
"s2": { "runtime_json" : "s2-runtime.json" },
|
||||
"s3": { "runtime_json" : "s3-runtime.json" }
|
||||
},
|
||||
"links": [
|
||||
["h1", "s1"], ["h11", "s1"], ["s1", "s2", "0", 0.5], ["s1", "s3"],
|
||||
["s3", "s2"], ["s2", "h2"], ["s2", "h22"], ["s3", "h3"]
|
||||
]
|
||||
}
|
||||
Reference in New Issue
Block a user