NAME

Net::Frame::Layer::NTP - NTP layer object

SYNOPSIS

   use Net::Frame::Simple;
   use Net::Frame::Layer::NTP qw(:consts);

   my $layer = Net::Frame::Layer::NTP->new(
      leap         => NF_NTP_LI_NOWARN,
      version      => 3,
      mode         => NF_NTP_MODE_CLIENT,
      stratum      => NF_NTP_STRATUM_UNSPEC,
      poll         => 0,
      precision    => 0,
      rootDelay    => 0,
      rootDisp     => 0,
      refId        => 0,
      refTime      => 0,
      refTime_frac => 0,
      org          => 0,
      org_frac     => 0,
      rec          => 0,
      rec_frac     => 0,
      xmt          => ntpTimestamp(time),
      xmt_frac     => 0,
   );

   #
   # Read a raw layer
   #

   my $layer = Net::Frame::Layer::NTP->new(raw => $raw);

   print $layer->print."\n";
   print 'PAYLOAD: '.unpack('H*', $layer->payload)."\n"
      if $layer->payload;

DESCRIPTION

This modules implements the encoding and decoding of the NTP layer.

RFC: ftp://ftp.rfc-editor.org/in-notes/rfc1305.txt

See also Net::Frame::Layer for other attributes and methods.

ATTRIBUTES

leap

NTP Leap Indicator. See CONSTANTS for more information.

version

NTP version.

mode

NTP mode. See CONSTANTS for more information.

stratum

NTP stratum. See CONSTANTS for more information.

poll

Maximum poll interval between messages in seconds to the nearest power of two.

precision

Precision of the local clock in seconds to the nearest power of two.

rootDelay

Total roundtrip delay to the primary reference source, in seconds with the fraction point between bits 15 and 16.

rootDisp

Maximum error relative to the primary reference source in seconds with the fraction point between bits 15 and 16.

refId

In the case of stratum 2 or greater, this is the IPv4 address of the primary reference host. In the case of stratum 0 or 1, this is a four byte, left-justified, zero padded ASCII string.

ref

ref_frac

The local time at which the local clock was last set or corrected and the fractional part.

org

org_frac

The local time when the client sent the request and the fractional part.

rec

rec_frac

The local time when the request was received by the server and the fractional part.

xmt

xmt_frac

The local time when the reply was sent from the server and the fractional part.

The following are inherited attributes. See Net::Frame::Layer for more information.

raw

payload

nextLayer

METHODS

new

new (hash)

Object constructor. You can pass attributes that will overwrite default ones. See SYNOPSIS for default values.

The following are inherited methods. Some of them may be overriden in this layer, and some others may not be meaningful in this layer. See Net::Frame::Layer for more information.

layer

computeLengths

pack

unpack

encapsulate

getLength

getPayloadLength

print

dump

USEFUL SUBROUTINES

Load them: use Net::Frame::Layer::NTP qw(:subs);

ntpTimestamp (time)

Create an NTP-adjusted timestamp.

ntp2date (time, frac)

Provided the NTP time and fracional timestamps, returns a human-readable time string.

CONSTANTS

Load them: use Net::Frame::Layer::NTP qw(:consts);

NF_NTP_ADJ

NTP adjustment (2208988800).

NF_NTP_LI_NOWARN

NF_NTP_LI_61

NF_NTP_LI_59

NF_NTP_LI_ALARM

NTP leap indicators.

NF_NTP_MODE_RSVD

NF_NTP_MODE_SYMACTIVE

NF_NTP_MODE_SYMPASSIVE

NF_NTP_MODE_CLIENT

NF_NTP_MODE_SERVER

NF_NTP_MODE_BROADCAST

NF_NTP_MODE_NTPCONTROL

NF_NTP_MODE_PRIVATE

NTP modes.

NF_NTP_STRATUM_UNSPEC

NF_NTP_STRATUM_PRIMARY

NF_NTP_STRATUM_UNSYNC

NTP stratums.

NF_NTP_REFID_GOES

NF_NTP_REFID_GPS

NF_NTP_REFID_GAL

NF_NTP_REFID_PPS

NF_NTP_REFID_IRIG

NF_NTP_REFID_WWVB

NF_NTP_REFID_DCF

NF_NTP_REFID_HBG

NF_NTP_REFID_MSF

NF_NTP_REFID_JJY

NF_NTP_REFID_LORC

NF_NTP_REFID_TDF

NF_NTP_REFID_CHU

NF_NTP_REFID_WWV

NF_NTP_REFID_WWVH

NF_NTP_REFID_NIST

NF_NTP_REFID_ACTS

NF_NTP_REFID_USNO

NF_NTP_REFID_PTB

NTP reference ID codes.

NF_NTP_KoD_ACST

NF_NTP_KoD_AUTH

NF_NTP_KoD_AUTO

NF_NTP_KoD_BCST

NF_NTP_KoD_CRYP

NF_NTP_KoD_DENY

NF_NTP_KoD_DROP

NF_NTP_KoD_RSTR

NF_NTP_KoD_INIT

NF_NTP_KoD_MCST

NF_NTP_KoD_NKEY

NF_NTP_KoD_RATE

NF_NTP_KoD_RMOT

NF_NTP_KoD_STEP

NTP kiss codes.

SEE ALSO

Net::Frame::Layer

AUTHOR

Michael Vincent

COPYRIGHT AND LICENSE

Copyright (c) 2016, Michael Vincent

You may distribute this module under the terms of the Artistic license. See LICENSE.Artistic file in the source distribution archive.