Description

Support a new kind of Bandwidth Trace that is more expressive and compact than mahimahi trace and can be replayed by rattan.
An example:

 {"RepeatedBwPatternConfig":{"pattern":[{"TraceBwConfig":[
    [1.0,[2.0,4.0,3.5,4.23,3.3]],
    [0.6,[1.0, 3.2, 3.5]]
]}],"count":0}}

denotes a (repeated) sequence of

1.0ms 2.0Mbps
1.0ms 4.0Mbps
1.0ms 3.5Mbps
1.0ms 4.23Mbps
1.0ms 3.3Mbps
0.6ms 1.0Mbps
0.6ms 3.2Mbps
0.6ms 3.5Mbps

.

Also, provide the funtion build_truncated for NormalBwConfig, where the impact of truncation (lower_bound and upper_bound field) on the mathematical expectation of the distribution is taking account by modifing the center of the distribution.

For example (as shown in the doc test), if we define a NormalBw with both a mean and std_dev of 12Mbps, lowerbound of 0 and no upperbound, under the random seed of 42, the average bandwidth of 100,000 samples are 12.97Mbps by the original build and 11.98Mbps by the new build_truncated.

How Has This Been Tested

Doc test has been wirtten to test the changes. The changes are incremental functions, structs, mods, and will not affect the other areas of the code.

Types of changes

New feature (non-breaking change which adds functionality)

Checklist

• Code follows the code style of this project.
• Changes follow the CONTRIBUTING guidelines.
• Update necessary documentation accordingly.
• Lint and tests pass locally with the changes.
• Check issues and pull requests first. You don't want to duplicate effort.

Other information