[−][src]Struct broker_ntp::protocol::Packet
Packet Header - The most important state variables from an external point of view are the packet header variables described here.
The NTP packet header consists of an integral number of 32-bit (4 octet) words in network byte order. The packet format consists of three components: the header itself, one or more optional extension fields, and an optional message authentication code (MAC).
+-----------+------------+-----------------------+ | Name | Formula | Description | +-----------+------------+-----------------------+ | leap | leap | leap indicator (LI) | | version | version | version number (VN) | | mode | mode | mode | | stratum | stratum | stratum | | poll | poll | poll exponent | | precision | rho | precision exponent | | rootdelay | delta_r | root delay | | rootdisp | epsilon_r | root dispersion | | refid | refid | reference ID | | reftime | reftime | reference timestamp | | org | T1 | origin timestamp | | rec | T2 | receive timestamp | | xmt | T3 | transmit timestamp | | dst | T4 | destination timestamp | | keyid | keyid | key ID | | dgst | dgst | message digest | +-----------+------------+-----------------------+
Format
The NTP packet is a UDP datagram [RFC0768]. Some fields use multiple words and others are packed in smaller fields within a word. The NTP packet header shown below has 12 words followed by optional extension fields and finally an optional message authentication code (MAC) consisting of the Key Identifier field and Message Digest field.
0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |LI | VN |Mode | Stratum | Poll | Precision | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Root Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Root Dispersion | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reference ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Reference Timestamp (64) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Origin Timestamp (64) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Receive Timestamp (64) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Transmit Timestamp (64) + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | . . . Extension Field 1 (variable) . . . | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | . . . Extension Field 2 (variable) . . . | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Key Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | dgst (128) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Fields
leap_indicator: LeapIndicator
version: Version
mode: Mode
stratum: Stratum
poll: i8
8-bit signed integer representing the maximum interval between successive messages, in log2 seconds. Suggested default limits for minimum and maximum poll intervals are 6 and 10, respectively.
precision: i8
8-bit signed integer representing the precision of the system clock, in log2 seconds. For instance, a value of -18 corresponds to a precision of about one microsecond. The precision can be determined when the service first starts up as the minimum time of several iterations to read the system clock.
root_delay: ShortFormat
Total round-trip delay to the reference clock, in NTP short format.
root_dispersion: ShortFormat
Total dispersion to the reference clock, in NTP short format.
reference_id: ReferenceIdentifier
reference_timestamp: TimestampFormat
Time when the system clock was last set or corrected.
origin_timestamp: TimestampFormat
Time at the client when the request departed for the server.
receive_timestamp: TimestampFormat
Time at the server when the request arrived from the client.
transmit_timestamp: TimestampFormat
Time at the server when the response left for the client.
Trait Implementations
impl Clone for Packet
[src]
impl ConstPackedSizeBytes for Packet
[src]
const PACKED_SIZE_BYTES: usize
[src]
impl Copy for Packet
[src]
impl Debug for Packet
[src]
impl Eq for Packet
[src]
impl Hash for Packet
[src]
fn hash<__H: Hasher>(&self, state: &mut __H)
[src]
fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,
1.3.0[src]
H: Hasher,
impl PartialEq<Packet> for Packet
[src]
impl ReadFromBytes for Packet
[src]
fn read_from_bytes<R: ReadBytesExt>(reader: R) -> Result<Self>
[src]
impl StructuralEq for Packet
[src]
impl StructuralPartialEq for Packet
[src]
impl WriteToBytes for Packet
[src]
fn write_to_bytes<W: WriteBytesExt>(&self, writer: W) -> Result<()>
[src]
Auto Trait Implementations
impl RefUnwindSafe for Packet
impl Send for Packet
impl Sync for Packet
impl Unpin for Packet
impl UnwindSafe for Packet
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized,
[src]
T: 'static + ?Sized,
impl<Src, Scheme> ApproxFrom<Src, Scheme> for Src where
Scheme: ApproxScheme,
[src]
Scheme: ApproxScheme,
type Err = NoError
The error type produced by a failed conversion.
fn approx_from(src: Src) -> Result<Src, <Src as ApproxFrom<Src, Scheme>>::Err>
[src]
impl<Dst, Src, Scheme> ApproxInto<Dst, Scheme> for Src where
Dst: ApproxFrom<Src, Scheme>,
Scheme: ApproxScheme,
[src]
Dst: ApproxFrom<Src, Scheme>,
Scheme: ApproxScheme,
type Err = <Dst as ApproxFrom<Src, Scheme>>::Err
The error type produced by a failed conversion.
fn approx_into(self) -> Result<Dst, <Src as ApproxInto<Dst, Scheme>>::Err>
[src]
impl<T> Borrow<T> for T where
T: ?Sized,
[src]
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
[src]
T: ?Sized,
fn borrow_mut(&mut self) -> &mut T
[src]
impl<T, Dst> ConvAsUtil<Dst> for T
[src]
fn approx(self) -> Result<Dst, Self::Err> where
Self: ApproxInto<Dst, DefaultApprox>,
[src]
Self: ApproxInto<Dst, DefaultApprox>,
fn approx_by<Scheme>(self) -> Result<Dst, Self::Err> where
Scheme: ApproxScheme,
Self: ApproxInto<Dst, Scheme>,
[src]
Scheme: ApproxScheme,
Self: ApproxInto<Dst, Scheme>,
impl<T> ConvUtil for T
[src]
fn approx_as<Dst>(self) -> Result<Dst, Self::Err> where
Self: ApproxInto<Dst, DefaultApprox>,
[src]
Self: ApproxInto<Dst, DefaultApprox>,
fn approx_as_by<Dst, Scheme>(self) -> Result<Dst, Self::Err> where
Scheme: ApproxScheme,
Self: ApproxInto<Dst, Scheme>,
[src]
Scheme: ApproxScheme,
Self: ApproxInto<Dst, Scheme>,
fn into_as<Dst>(self) -> Dst where
Self: Into<Dst>,
[src]
Self: Into<Dst>,
fn try_as<Dst>(self) -> Result<Dst, Self::Err> where
Self: TryInto<Dst>,
[src]
Self: TryInto<Dst>,
fn value_as<Dst>(self) -> Result<Dst, Self::Err> where
Self: ValueInto<Dst>,
[src]
Self: ValueInto<Dst>,
impl<T> From<T> for T
[src]
impl<T, U> Into<U> for T where
U: From<T>,
[src]
U: From<T>,
impl<T> ToOwned for T where
T: Clone,
[src]
T: Clone,
type Owned = T
The resulting type after obtaining ownership.
fn to_owned(&self) -> T
[src]
fn clone_into(&self, target: &mut T)
[src]
impl<Src> TryFrom<Src> for Src
[src]
type Err = NoError
The error type produced by a failed conversion.
fn try_from(src: Src) -> Result<Src, <Src as TryFrom<Src>>::Err>
[src]
impl<T, U> TryFrom<U> for T where
U: Into<T>,
[src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
[src]
impl<Src, Dst> TryInto<Dst> for Src where
Dst: TryFrom<Src>,
[src]
Dst: TryFrom<Src>,
type Err = <Dst as TryFrom<Src>>::Err
The error type produced by a failed conversion.
fn try_into(self) -> Result<Dst, <Src as TryInto<Dst>>::Err>
[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
[src]
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
[src]
impl<Src> ValueFrom<Src> for Src
[src]
type Err = NoError
The error type produced by a failed conversion.
fn value_from(src: Src) -> Result<Src, <Src as ValueFrom<Src>>::Err>
[src]
impl<Src, Dst> ValueInto<Dst> for Src where
Dst: ValueFrom<Src>,
[src]
Dst: ValueFrom<Src>,