mirror of
https://git.rwth-aachen.de/acs/public/villas/node/
synced 2025-03-30 00:00:11 +01:00
Steffen Vogel
a681ca14a6
git-svn-id: https://zerberus.eonerc.rwth-aachen.de:8443/svn/s2ss/trunk@84 8ec27952-4edc-4aab-86aa-e87bb2611832
29 lines
1.4 KiB
Markdown
29 lines
1.4 KiB
Markdown
# Network Emulation
|
|
|
|
S2SS supports the emulation of wide-area network characterisics.
|
|
|
|
For this an existing network emulator called 'netem' is used.
|
|
Netem is part of the Linux kernel and therefore shipped with most distributions by default.
|
|
Netem is implemented as a queuing discipline.
|
|
This discipline define the order and point in time when packets will be send over the network.
|
|
|
|
S2SS only takes care of setup and initalizing the netem queuing discipline inside the kernel.
|
|
For this the iproute2 software package (`ip` & `tc` commands) must be installed.
|
|
The configuration is done via the config file.
|
|
Look at `etc/example.conf` for a section called `netem` or `tc-netem(8)` for more details.
|
|
|
|
## Custom delay distributions
|
|
|
|
Netem supports loading custom delay distributions.
|
|
|
|
1. Load and compile the netem tools from:
|
|
https://git.kernel.org/cgit/linux/kernel/git/shemminger/iproute2.git/tree/netem
|
|
2. Create a custom distribution by following the steps described here:
|
|
https://git.kernel.org/cgit/linux/kernel/git/shemminger/iproute2.git/tree/README.distribution
|
|
3. Put the generated distrubtion with the suffix `.dist` in the `tc` lib directory: `/usr/lib/tc/`.
|
|
4. Load the distribution specifying the basename in the server config.
|
|
|
|
## Links
|
|
|
|
- http://www.linuxfoundation.org/collaborate/workgroups/networking/netem
|
|
- https://git.kernel.org/cgit/linux/kernel/git/shemminger/iproute2.git/tree/README.iproute2+tc
|