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Every call to the Web API interfaces require HTTP Authorization header with a Bearer authentication scheme: Authorization: Bearer BgV57K7vCwGE2vXex7BcgahRMeYoBQgdSJWhcQoJXhF4. Authorization tokens for this header can be obtained by an administrator from Web API Keys tab in the Contract Signatures Apps page. Every key is associated with the following security attributes which define its:
Privileges - to which interfaces the key may be used
Not valid before - from when the key may be used
Not valid after - till when the key may be used
Allowed IPs - from what IPs (ranges) the key may be used
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