readme.md

Technical Details

Building Blocks Structure

Trust attributes

Trust attribute are integer value in [0, 1, 2], from worst to best.

sd = 1

Requirements

Requirements are a tuple of the form: (range, cardinality), where:

• range is a list of int:
  • the first (min) in a range of [0, 1, 2]
  • the second (max) is always 2, to define an open range [x, +inf)
• cardinality is an int in the range [0, 1]

req = ([0, 2], 1)

Policy

Policies are list of floats: [min_0, min_1], where:

• min_0 is the minimum value to accept the collaboration
• min_1 is the best value to perform a better action

policy = [0.3, 0.6]

Changes

A change is defined as a tuple of the form: (service data, new value), where:

• service data is the "name" of the service data that change
• new value is the new service data value

ch = ('sd0', 2)

Service

Each service is represented as a dict that contains:

• service data:
  • for each service data there is a key of the form 'sdX', for instance: 'sd0', 'sd1', etc, and the associated value
• requirements:
  • for each requirement there is a key of the form 'reqX', for instance: 'req0', 'req1', etc, and the associated value
• policy:
  • the dictionary has a 'policy' key with the associated value
• changes:
  • the dictionary has a 'change' key with an array of changes

service = {
    'sd0': 0
    'req0': ([1, 2], 1)
    'sd1': 2
    'req1': ([0, 2], 0)
    'sd2': 1
    'req2': ([2, 2], 1)
    'policy': [0.3, 0.6]
    'change': [('sd0', 1), ('sd1', 0), ('sd2', 2)]
}

System

After the first negotiation, the system is represented as a list of tuple of the form: (service X, satisfaction X), where:

• service X is a dict
• satisfaction X is a float

system = [
    (
        {
            'sd0': 2
            'req0': ([1, 2], 1)
            'policy': [0.3, 0.6]
            'change': [('sd0', 1)]
        },
        0.7
    ),
    (
        {
            'sd0': 2
            'req0': ([1, 2], 1)
            'policy': [0.3, 0.6]
            'change': [('sd0', 1)]
        },
        0.9
    )
]

To access values after the handshake you can follow this:

1. access to a service: system[i][0] → get the service at position i
2. access to a satisfaction: system[i][1] → get the satisfaction of the service at position i
3. access to the value of 'sd0': system[i][0]['sd0'] → get the value of the service data 'sd0' of the service at position i
4. perform a change: system[i][0][system[i][0]['change'][0][0]] = system[i][0]['change'][0][1] → change the value of the service data indicated in the first change

Explanation:

1. system = [(service0, sd0), ...]
   • → system[0] = (service0, sd0)
   • → system[0][0] = service0
2. system = [(service0, sd0), ...]
   • → system[0] = (service0, sd0)
   • → system[0][1] = sd0
3. system = [(service0, sd0), ...]
   • → system[0] = (service0, sd0)
   • → system[0][0] = service0 == {'sd0': 1, ...}
   • → system[0][0]['sd0'] = 1
4. system = [(service0, sd0), ...]
   • → system[0] = (service0, sd0)
   • → system[0][0] = service0 == {..., 'change': [('sd0', 2)]}
   • → system[0][0]['change'] = [('sd0', 2)]
   • → system[0][0]['change'][0] = ('sd0', 2)
   • → system[0][0]['change'][0][0] = 'sd0'
   • → system[0][0]['change'][0][1] = 2
   • → system[0][0][system[0][0]['change'][0][0]] = service0['sd0']
   • → system[0][0][system[0][0]['change'][0][0]] = system[0][0]['change'][0][1] == service0['sd0'] = 2

In a loop:

for service in system: 
    print(service[0]['change'])

>>> [('sd0', 1), ('sd1', 0)]

Datasets

Each setting in Section 6.1 corresponds to an individual dataset, containing the services described in terms of trust attributes, requirements, policies, and so on. Each dataset is a CSV file containing the following columns:

• service: represents the index of the service, i.e., 0, 1, 2, ...
• setting: represents the name of the setting, i.e., G0.0.0, G0.0.1, ...
• sdnX: represents the value of the X-th trust attribute, i.e., 0, 1, 2
• reqX: represents the requirements on trust X-th attribute, i.e., ([0, 2], 0), ([1, 2], 1), ...
• policy: represents the service policy, i.e., [0.3, 0.6], [0.6, 0.9], ...
• change: represents the changes of a service, i.e., [('sd0', 0), ('sd2', 1)], [], [('sd3', 0)], ...

An example:

service	setting	sd0	req0	sd1	req1	policy	change
0	G0.0.0	1	([0, 2], 1)	2	([1, 2], 0)	[0.3, 0.6]	[('sd0', 2)]
1	G0.0.0	2	([2, 2], 0)	1	([0, 2], 0)	[0.6, 0.9]	[('sd0', 1)]
2	G0.0.0	0	([1, 2], 1)	2	([0, 2], 1)	[0.3, 0.6]	[('sd0', 1), ('sd1', 1)]