### Instruction:

Extract the cause and effect entities from the following sentence:
The link transfers the clock signals in both directions (space-to-ground and ground-to-space) allowing the received signal to be compared with the local clock at both ends

### Assistant:

KEYWORD: allowing
VARIABLE: The link
CONDITION: transfers the clock signals in both directions
EFFECT_1: the received signal to be compared with the local clock at both ends
NOT_RELEVANT: (space-to-ground and ground-to-space)
CAUSE_1: The link transfers the clock signals in both directions

