Relationship between security services

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flowchart
S[Security Services] 
S --> E[Entity]
S --> D[Data]
E --1--> ID[Entity Identity];
D --2--> DI[Data Integrity];
D --3--> DC[Data Confidentiality];
ID --4--> EA[Entity Authentication];
ID --5--> DOA[Data Origin Authentication];
DI --6--> DOA --7--> NR[Non-Repudiation];

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1. Entity Identity refers to a user or process interacting with a security service.
2. Data Integrity attests whether modification of data occurred.
3. Data Confidentiality, achieved primarily through encryption, generally does not provide assurance of who sent the data nor that it is correct (identity and integrity).
4. Entity Authentication attests that a given entity is involved and currently active in a communication session. It requires a freshness mechanism and is used when accessing resources. It does not necessarily require the origin of any data to be checked.
5. Data Origin Authentication implies proof of the Identity the data originates from.
6. Data Origin Authentication implies Data Integrity, but not the other way around. If we're not sure about the origin of the data, we cannot attest to its integrity.
7. Non-Repudiation cannot be provided without Data Origin Authentication (and hence Data Integrity). In other words, having the assurance that a particular event was performed by an entity, also requires assurances about the origin of the data.