gnupg1-curl 1.4.21-2ubuntu1 (s390x binary) in ubuntu zesty

 GnuPG is GNU's tool for secure communication and data storage.
 It can be used to encrypt data and to create digital signatures.
 It includes an advanced key management facility and is compliant
 with the proposed OpenPGP Internet standard as described in RFC 4880.
 .
 This package contains the keyserver helper tools built with libcurl,
 which replace the ones in the gnupg1 package built with the "curl
 shim" variant of gnupg1. This package provides support for HKPS
 keyservers.