{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:4XIOUJFWZRZJA5NRSLCNHPFH4V","short_pith_number":"pith:4XIOUJFW","canonical_record":{"source":{"id":"1803.10327","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2018-03-27T21:00:27Z","cross_cats_sorted":["cs.FL","cs.LO"],"title_canon_sha256":"44233f3f238f0549e90ffd070843e39d33bc4079851663bfba406f6dcdf1d475","abstract_canon_sha256":"26ec862d053644ec2da01a524851d3d65156de4e795978230fdd6b506995b2e5"},"schema_version":"1.0"},"canonical_sha256":"e5d0ea24b6cc729075b192c4d3bca7e546cf34553b70d370b3a1bf690dd91ee0","source":{"kind":"arxiv","id":"1803.10327","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.10327","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"arxiv_version","alias_value":"1803.10327v1","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.10327","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"pith_short_12","alias_value":"4XIOUJFWZRZJ","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_16","alias_value":"4XIOUJFWZRZJA5NR","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_8","alias_value":"4XIOUJFW","created_at":"2026-05-18T12:32:05Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:4XIOUJFWZRZJA5NRSLCNHPFH4V","target":"record","payload":{"canonical_record":{"source":{"id":"1803.10327","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2018-03-27T21:00:27Z","cross_cats_sorted":["cs.FL","cs.LO"],"title_canon_sha256":"44233f3f238f0549e90ffd070843e39d33bc4079851663bfba406f6dcdf1d475","abstract_canon_sha256":"26ec862d053644ec2da01a524851d3d65156de4e795978230fdd6b506995b2e5"},"schema_version":"1.0"},"canonical_sha256":"e5d0ea24b6cc729075b192c4d3bca7e546cf34553b70d370b3a1bf690dd91ee0","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:19:46.859441Z","signature_b64":"76ZSsLXP9S11jTM/1PyOOLPOBTpd2JhZt76gDgFBm6jDdDlqibqsIKWbDzHbuLba3NPRusryRLGSQUYud3ZYBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e5d0ea24b6cc729075b192c4d3bca7e546cf34553b70d370b3a1bf690dd91ee0","last_reissued_at":"2026-05-18T00:19:46.858707Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:19:46.858707Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1803.10327","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:19:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/YnFxH1OKtVIYRmMNlgOEa63/yKNTFA1lUIhRF9XvBqBaPOwqPLzalEhXO3kHGDQI0JiDxISg0h9T0BV/kO4CA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T16:51:20.873999Z"},"content_sha256":"6964253540c0b3929d70850d699fd68e6365de730282d719d80f4030823b5174","schema_version":"1.0","event_id":"sha256:6964253540c0b3929d70850d699fd68e6365de730282d719d80f4030823b5174"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:4XIOUJFWZRZJA5NRSLCNHPFH4V","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"An Experiment in Ping-Pong Protocol Verification by Nondeterministic Pushdown Automata","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.FL","cs.LO"],"primary_cat":"cs.PL","authors_text":"Dept. of Computer Science, Robert Gl\\\"uck (DIKU, University of Copenhagen)","submitted_at":"2018-03-27T21:00:27Z","abstract_excerpt":"An experiment is described that confirms the security of a well-studied class of cryptographic protocols (Dolev-Yao intruder model) can be verified by two-way nondeterministic pushdown automata (2NPDA). A nondeterministic pushdown program checks whether the intersection of a regular language (the protocol to verify) and a given Dyck language containing all canceling words is empty. If it is not, an intruder can reveal secret messages sent between trusted users. The verification is guaranteed to terminate in cubic time at most on a 2NPDA-simulator. The interpretive approach used in this experim"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.10327","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:19:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cLK2tWSKbYAWJ/7vn5a7c7JABgGH7/446Wv1rVdhdbpkpDi3AuUl9lIML6zXQ4rO82hrufMYbEVHvZjus0inAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T16:51:20.874621Z"},"content_sha256":"b8f4b653a1e69138d00f300b2b28795596f3a27a911d0945904924fafc4b157f","schema_version":"1.0","event_id":"sha256:b8f4b653a1e69138d00f300b2b28795596f3a27a911d0945904924fafc4b157f"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/bundle.json","state_url":"https://pith.science/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-28T16:51:20Z","links":{"resolver":"https://pith.science/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V","bundle":"https://pith.science/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/bundle.json","state":"https://pith.science/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4XIOUJFWZRZJA5NRSLCNHPFH4V/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:4XIOUJFWZRZJA5NRSLCNHPFH4V","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"26ec862d053644ec2da01a524851d3d65156de4e795978230fdd6b506995b2e5","cross_cats_sorted":["cs.FL","cs.LO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2018-03-27T21:00:27Z","title_canon_sha256":"44233f3f238f0549e90ffd070843e39d33bc4079851663bfba406f6dcdf1d475"},"schema_version":"1.0","source":{"id":"1803.10327","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.10327","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"arxiv_version","alias_value":"1803.10327v1","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.10327","created_at":"2026-05-18T00:19:46Z"},{"alias_kind":"pith_short_12","alias_value":"4XIOUJFWZRZJ","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_16","alias_value":"4XIOUJFWZRZJA5NR","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_8","alias_value":"4XIOUJFW","created_at":"2026-05-18T12:32:05Z"}],"graph_snapshots":[{"event_id":"sha256:b8f4b653a1e69138d00f300b2b28795596f3a27a911d0945904924fafc4b157f","target":"graph","created_at":"2026-05-18T00:19:46Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"An experiment is described that confirms the security of a well-studied class of cryptographic protocols (Dolev-Yao intruder model) can be verified by two-way nondeterministic pushdown automata (2NPDA). A nondeterministic pushdown program checks whether the intersection of a regular language (the protocol to verify) and a given Dyck language containing all canceling words is empty. If it is not, an intruder can reveal secret messages sent between trusted users. The verification is guaranteed to terminate in cubic time at most on a 2NPDA-simulator. The interpretive approach used in this experim","authors_text":"Dept. of Computer Science, Robert Gl\\\"uck (DIKU, University of Copenhagen)","cross_cats":["cs.FL","cs.LO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2018-03-27T21:00:27Z","title":"An Experiment in Ping-Pong Protocol Verification by Nondeterministic Pushdown Automata"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.10327","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:6964253540c0b3929d70850d699fd68e6365de730282d719d80f4030823b5174","target":"record","created_at":"2026-05-18T00:19:46Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"26ec862d053644ec2da01a524851d3d65156de4e795978230fdd6b506995b2e5","cross_cats_sorted":["cs.FL","cs.LO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.PL","submitted_at":"2018-03-27T21:00:27Z","title_canon_sha256":"44233f3f238f0549e90ffd070843e39d33bc4079851663bfba406f6dcdf1d475"},"schema_version":"1.0","source":{"id":"1803.10327","kind":"arxiv","version":1}},"canonical_sha256":"e5d0ea24b6cc729075b192c4d3bca7e546cf34553b70d370b3a1bf690dd91ee0","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e5d0ea24b6cc729075b192c4d3bca7e546cf34553b70d370b3a1bf690dd91ee0","first_computed_at":"2026-05-18T00:19:46.858707Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:19:46.858707Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"76ZSsLXP9S11jTM/1PyOOLPOBTpd2JhZt76gDgFBm6jDdDlqibqsIKWbDzHbuLba3NPRusryRLGSQUYud3ZYBA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:19:46.859441Z","signed_message":"canonical_sha256_bytes"},"source_id":"1803.10327","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:6964253540c0b3929d70850d699fd68e6365de730282d719d80f4030823b5174","sha256:b8f4b653a1e69138d00f300b2b28795596f3a27a911d0945904924fafc4b157f"],"state_sha256":"3eeec4b39f314d9c793e6ebc1c5c125ab8b4912e2789a5ef0534dfdfd329dd9c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"YGA/VIQ2+XhuA97WYRKVa48yvELlFKmchvLQCps//KZhDr3EXRE6HYkTBR1X4afR1WXCRimqFbquDMfgp3QGDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T16:51:20.877997Z","bundle_sha256":"77c8d222034f5fa54a271f6c96f6af97b17422f5554bf1f9e064e49f4d243314"}}