Automating SCION Bandwidth Tests

Overview

This example deploys bandwidth test servers in multiple SCION autonomous systems and configures ScionBwtestClientService in one AS. After the container starts and waits for a specified period, the client initiates measurements using a predefined target and bidirectional test parameters. A shared directory makes the test output directly accessible from the host machine. By incorporating manual testing steps into the scenario configuration, the example supports repeated execution of the same measurement. You can further organize experiments with different targets, path preferences, or load parameters, then collect logs to compare the results.

SCION Bandwidth Test Client

This example demonstrates how to set up a SCION network for conducting bandwidth tests, using scion-bwtestclient, between Autonomous Systems (ASes) using SeedEmu. It includes configuring ASes, routers, hosts, and bandwidth test services.

Initializing the bwtestclient Service

First, we initialize the bwtestclient service.

from seedemu.services import ScionBwtestClientService
# other imports

# Create bandwidth test services
bwtest = ScionBwtestService()
bwtestclient = ScionBwtestClientService()

Setting up Bandwidth Test Services

First we create scion-bwtestserver in every AS.

# Bandwidth test server in AS-150
as150.createHost('bwtest').joinNetwork('net0', address='10.150.0.30')
bwtest.install('bwtest150').setPort(40002)
emu.addBinding(Binding('bwtest150', filter=Filter(nodeName='bwtest', asn=150)))

# Bandwidth test server in AS-151
as151.createHost('bwtest').joinNetwork('net0', address='10.151.0.30')
bwtest.install('bwtest151')
emu.addBinding(Binding('bwtest151', filter=Filter(nodeName='bwtest', asn=151)))

# Bandwidth test server in AS-152
as152.createHost('bwtest').joinNetwork('net0', address='10.152.0.30')
bwtest.install('bwtest152')
emu.addBinding(Binding('bwtest152', filter=Filter(nodeName='bwtest', asn=152)))

# Bandwidth test server in AS-153
as153.createHost('bwtestserver').joinNetwork('net0', address='10.153.0.30')
bwtest.install('bwtest153')
emu.addBinding(Binding('bwtest153', filter=Filter(nodeName='bwtestserver', asn=153)))

Now we create a scion-bwtestclient in one of the ASes

# Bandwidth test client in AS-153
as153.createHost('bwtestclient').joinNetwork('net0', address='10.153.0.31').addSharedFolder("/var/log", "/absolute/path/to/logs/on/host")
bwtestclient.install('bwtestclient153').setServerAddr('1-151,10.151.0.30').setWaitTime(20)
emu.addBinding(Binding('bwtestclient153', filter=Filter(nodeName='bwtestclient', asn=153)))

Notes:

the addSharedFolder(“nodePath”,”hostPath”) function makes sure that we can see the bwtestclient output without attaching to the container
the setServerAddr() function specifies the server address of the bwtestserver
the setWaitTime() function sets the number of seconds to wait after the container started before running the test. The default is 60 seconds.
there are also other functions:
- setPort() – setting the port the server listens on
- setPreference() – set the preference for sorting paths (check bwtester documentation for more details)
- setCS() – Client->Server test parameter (default “3,1000,30,80kbps”)
- setSC() – Server->Client test parameter (default “3,1000,30,80kbps”)

Rendering and Compilation

We add the configured layers to the emulator, render the network topology, and compile the configuration into Docker containers.

# Rendering
emu.addLayer(bwtest)
emu.addLayer(bwtestclient)

Source: SEED Emulator · S07 README

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