Homa Transport Protocol on The Network Simulator, Version 3

Maintained by Serhat Arslan

This is an implementation of the Homa Transport Protocol described in [1]. It implements a connectionless, reliable, low latency message delivery service.

[1] Behnam Montazeri, Yilong Li, Mohammad Alizadeh, and John Ousterhout. 2018. Homa: a receiver-driven low-latency transport protocol using network priorities. In Proceedings of the 2018 Conference of the ACM Special Interest Group on Data Communication (SIGCOMM '18). Association for Computing Machinery, New York, NY, USA, 221–235. DOI:https://doi-org.stanford.idm.oclc.org/10.1145/3230543.3230564

This implementation is created in guidance of the protocol creators and maintained as the ns-3 implementation of the protocol. The IPv6 compatibility of the protocol is left for future work.

Table of Contents:

1. An overview
2. Building ns-3
3. Running ns-3
4. Getting access to the ns-3 documentation
5. Working with the development version of ns-3

Note: Much more substantial information about ns-3 can be found at https://www.nsnam.org

An Open Source project

ns-3 is a free open source project aiming to build a discrete-event network simulator targeted for simulation research and education. This is a collaborative project; we hope that the missing pieces of the models we have not yet implemented will be contributed by the community in an open collaboration process.

The process of contributing to the ns-3 project varies with the people involved, the amount of time they can invest and the type of model they want to work on, but the current process that the project tries to follow is described here: https://www.nsnam.org/developers/contributing-code/

This README excerpts some details from a more extensive tutorial that is maintained at: https://www.nsnam.org/documentation/latest/

Building ns-3

The code for the framework and the default models provided by ns-3 is built as a set of libraries. User simulations are expected to be written as simple programs that make use of these ns-3 libraries.

To build the set of default libraries, you need to use the tool 'waf'. Detailed information on how to use waf is included in the file doc/build.txt

However, the real quick and dirty way to get started is to type the command

./waf configure

followed by

./waf

in the directory which contains this README file. The files built will be copied in the build/ directory.

The current codebase is expected to build and run on the set of platforms listed in the release notes file.

Other platforms may or may not work: we welcome patches to improve the portability of the code to these other platforms.

Running ns-3 with a simple HomaL4Protocol test

On recent Linux systems, once you have built ns-3, it should be easy to run the sample programs with the following command, such as:

./waf --run scratch/HomaL4Protocol-simple-test

That program should generate a HomaL4ProtocolSimpleTestMsgTraces.tr text trace file which includes logs related to creation and delivery of messages. The program source can be found in the scratch/HomaL4Protocol-simple-test.cc.

Getting access to the ns-3 documentation

Once you have verified that your build of ns-3 works by running the HomaL4Protocol-simple-test as outlined in 3) above, it is quite likely that you will want to get started on reading some ns-3 documentation.

All of that documentation should always be available from the ns-3 website: https://www.nsnam.org/documentation/.

This documentation includes:

• a tutorial

• a reference manual

• models in the ns-3 model library

• a wiki for user-contributed tips: https://www.nsnam.org/wiki/

• API documentation generated using doxygen: this is a reference manual, most likely not very well suited as introductory text: https://www.nsnam.org/doxygen/index.html

Working with the development version of ns-3

If you want to download and use the development version of ns-3, you need to use the tool git. A quick and dirty cheat sheet is included in the manual, but reading through the git tutorials found in the Internet is usually a good idea if you are not familiar with it.

If you have successfully installed git, you can get a copy of the development version with the following command:

git clone https://github.com/serhatarslan-hub/HomaL4Protocol-ns-3.git

However, we recommend to follow the GitHub guidelines for starters, that includes creating a GitHub account, forking the ns-3-dev project under the new account's name, and then cloning the forked repository. You can find more information in the manual.

List of related files for HomaL4Protocol based on NS3

Created files

scratch/homa-official-simple-test.cc : A simple test simulation to verify the Homa Protocol works.

scratch/homa-paper-reproduction.cc : The large scale simulation to reproduce the scenario described in the paper.

src/applications/model/msg-generator-app.cc/h : The application environment to create given workloads.

src/internet/model/homa-header.cc/h: The packet header declaration for HomaL4Protocol.

src/internet/model/homa-l4-protocol.cc/h: The main protocol file to define the Homa behavior.

src/internet/model/homa-socket-factory.cc/h: Class that creates Homa sockets.

src/internet/model/homa-socket.cc/h : Homa socket declaration (very similar to UDP sockets)

src/traffic-control/model/pfifo-homa-queue-disc.cc/h : Priority queueing on switches based on packet priorities defined by HomaL4Protocol.

Modified Files

src/internet/helper/internet-stack-helper.cc : HomaL4Protocol is added as a part of default InternetStack.

src/internet/model/ipv4-global-routing.cc : ECMP options added in addition to random, ie per-flow.

src/internet/model/ipv4-l3-protocol.cc/h : IP fragmentation made configurable.

src/point-to-point/model/point-to-point-net-device.cc/h : Added an API to get the line rate of the device.