Link Encryption definition in Computer Security terms:
Definition(s): Encryption of information between nodes of a communications system.
Source(s): CNSSI 4009-2015
Link encryption encrypts all of the data along a communications path (e.g., a satellite link, telephone circuit, or Tl line). Since link encryption also encrypts routing data, communications nodes need
to decrypt the data to continue routing.
Source(s): NIST SP 800-12
reference: CSRC Glossary