[ntp:questions] Petition to FCC for accurate timestamps and NTP

Tony Rutkowski trutkowski at verisign.com
Mon Jun 4 11:55:57 UTC 2007

Hi David,

>Attachements not allowed to a text newsgroup.  Please provide a URL.

enter "RM-11376" in box 1 and click on search.
You will get the three documents in the docket.
The public notice is 2 pages and describes the comment
process created.  The 74 page PET RM describes the
proposed requirements.  The relevant NTP related
section is provided below.  The explicit NPT references
occur near the end of the section

>Please be aware that the rest of the world no longer follows the US.  Were
>an international body involved, others might be more likely to listen.

Almost every country has a similar requirement. The standards
followed globally are those of ETSI and have a required
accuracy of one second, but with a recently changed precision
expression option to one millisecond.  The 200 millisecond
requirement and reference to NTP will likely proceed in ETSI.

Hope this helps.


Before the
Washington, D.C. 20554

Filed May 15 2007
United States Department of Justice
[At Page 19]

B. Timing Information (Time Stamping)

1. Timing Information Is a Required CII Capability

Timing information is information that distinguishes and properly 
associates CII
with the content of several communications that occur at 
approximately the same time.
A timing information capability would require a carrier to time stamp 
each CII message
within a specific amount of time from when the event triggering the 
message occurred,
and send the CII message to law enforcement within a defined amount 
of time after the
triggering event. Together, this allows law enforcement to associate 
the CII message
with the communication content information (i.e., the communication) 
and associate the
party contacted by the subject with the communication.

The Commission already has held in the Third R&O that a timing information
requirement is a CII capability required by CALEA Sections 102(2) and 
Specifically, the Commission stated:

We will adopt a timing information requirement as an
assistance capability requirement of section 103 of CALEA.

      First, we find that time stamping is call-identifying
      information as defined in section 102(2) of CALEA. This
      information is needed to distinguish and properly associate
      the call identifying information with the content of several
      calls occurring at approximately the same time. In other
      words, time stamp information is needed to identify "the
      origin, direction, destination, or termination" of any given
      call and, thus, fits within the statutory definition of section
      102(2). Second, we find that delivery of call identifying
      information, including time stamp information, to the [law
      enforcement agency] must, pursuant to section 103(a)(2), be
      provided in such a timely manner to allow that information
      "to be associated with the communication to which it

In adopting a timing information requirement, the Commission also adopted
specific parameters for delivery of the required timing information. 
Specifically, a CII
message must be transmitted to the law enforcement agency's Collection Function
within eight seconds of its receipt by the intercept access point 
("IAF") 95% of the time,
and with an accuracy within 200 milliseconds.48  The timing 
information requirement -
including the specific parameters for delivery of the required timing 
information - was
codified in the Commission's rules49 and remains in force today. As a 
result of the
Commission's conclusions in the Third R&O and the adoption of a rule 
requiring a
timing information capability, the timing information (time stamping) 
capability was
added by industry to J-STD-025-A.j0 As more fully discussed below, 
there is no reason
why this capability should not have been included in J-STD-025-B.

2. The Commission Should Reaffirm That Timing Information
     (Time Stamping) Is a Required Capability

Despite the requirements of CALEA Section 103(a)(2) and the Commission's
directive in the Third R&V, J-STD-025-B does not contain language 
that establishes
specific parameters for delivery of the required timing information 
(time stamping). As
a result, unlike its predecessor J-STD-025-A, J-STD-025-B is 
ambiguous as to whether
the Commission's timing requirements for accuracy and delivery of CII 
apply to packet
data services.

J-STD-025-Bs ambiguity over the timing information (time stamping) capability
arises from a footnote added to a June 2004 version of J-STD-025-B at 
the request of an
industry representative. The footnote stated that the Third R&O's 
timing "requirement
is established by the [Commission] for circuit-mode 
only."51  Notwithstanding that the
Commission's Third R&O clearly addressed both circuit-mode and packet-mode
communications,52 certain TIA members took the position - based on 
the addition of the
footnote - that the Commission's time stamping requirement does not 
apply to any
packet data services. Although the footnote subsequently was removed 
from J-STD-
025-B, that standard is silent as to whether timing information (time 
stamping) must be
provided, and several TIA members continue to this day to dispute 
whether the timing
requirements set forth in the Third R&O apply to packet data services.

The Commission held in the Third R&O that circuit- and packet-mode
communications services are each subject to CALEA, and adopted 
capabilities in the
Third R&O that apply to both circuit- and packet-mode services.53 Given the
Commission's holding, it is entirely unclear why certain TIA members 
continue to
maintain that the time stamping requirement does not apply to packet 
data services.
The Commission should make clear that, irrespective of what the 
standard states,
carriers nonetheless must comply with the letter and spirit of the 
Commission's timing
information capability rule.

Although the Commission concluded in the Third R&O that J-STD-025 (later J-
STD-025-A) was not a sufficient CALEA solution for packet-mode services,54 the
Commission set a September 2001 deadline for packet-mode compliance,55 and
specifically requested that TIA "study CALEA solutions for 
packet-mode technology
and report to the Commission [by September 20001 on steps that can be 
taken, including
particular amendments to J-STD-025."56  It is clear from the 
Commission's statements that
such packet-mode compliance would include providing the capabilities 
adopted in the
Third RDO via amendments to J-STD-025 - i.e., in J-STD-025-B. 
Therefore, there is
nothing in the Third RbO that suggests that the capabilities adopted 
therein - including
the timing information (time stamping) requirement - do not apply to 
(data) services.57

Nor is there anything in the Third RbO that would preclude the application of
the timing information requirements specified therein to packet-mode 
(data) services.
In fact, the Commission's rules contain no distinction about the type 
of communications
( i e , circuit-mode vs. packet-mode) to which the timing capability 
applies; the rules
state only that "wireline, cellular, and PCS telecommunications 
carriers shall provide to
a [law enforcement agency] [a timing information capability]."58

Highly accurate timing information is critical for a number of 
important reasons.
First, as the Commission recognized, time stamping is critical to 
proper correlation of
the CII events to the associated intercepted communications content 
stream. 59 The less
accurate the time stamp, the greater the possibility that multiple 
events occurring in the
same time frame will lead to a misinterpretation of the sequence of CII events.

Second, unlike traditional circuit-switched networks, electronic intercepts in
packet data sessions may occur at multiple points (nodes) within a 
carrier's network. In
fact, because of the diffuse nature of packet-based technologies 
(i.e., that packet data
sessions can occur at multiple nodes in a carrier's network and 
involve multiple IAPs),
time stamping is even more critical in the packet-mode communications 
context than
the circuit-mode context. Thus, it is critically important that time 
stamping occur so
that the CII events between these multiple network nodes can be 
properly correlated
with the communications content.

Third, multiple simultaneous packet data sessions can be established 
by a user of
packet-mode services. A time stamp capability is needed to correlate 
the CII events and
communications content on a timeline for each session, and to permit 
law enforcement
to distinguish between CII events for each different session. 
Moreover, to the extent
that two communications sessions may be related, this level of 
accuracy will allow law
enforcement to correlate, where necessary, the two sessions.

Finally, accurate time stamping for packet data intercepts - regardless of the
format used to deliver the intercepted communications to law 
enforcement - is crucial
to law enforcement's reconstruction of the sequence of events contained in the

The lack of accurate timing information (time stamping) requirements frustrates
CALEA's purpose because it impedes law enforcement's ability 
accurately to associate
CII with communications content. Indeed, as a practical matter, 
without accurate time
stamping, law enforcement may not be able to correctly determine when 
the CII events
occurred or correlate them with the communications content. As a 
result, a court order
can be frustrated as much as if the information were not delivered to 
law enforcement
at all.

Given that packet mode communications are subject to CALEA,60 and in light of
the Commission's conclusion in the Third R&0 that timing information 
is CII under
Section 102(2), 61 there is no rational basis for omitting a timing 
information (time
stamping) assistance capability from a packet mode standard such as 
Indeed, the fact that a time stamping capability is more significant 
with respect to
packet-mode communications should compel its inclusion in such standards.

Therefore, in order to resolve any ambiguity, DOJ requests that the Commission
reaffirm that a timing information (time stamping) requirement is 
applicable to packet
data services, regardless of the technology used by the carrier to 
provide the service. In
addition, DOJ asks the Commission to require that carriers provide, 
at a minimum, a
timing information (time stamping) capability that meets the 
requirements prescribed
in the Third R&O and codified in the Commission's rules - including 
the specific
parameters for delivery of the required timing information. 62, 63


46  Third R&O at 16835 para. 95.

47 Id.

48 Id. at 16835 para. 96.

49 47 C.F.R. Secs.  64.2202, 64.2203(c) (now contained in 47 C.F.R. 
secs. 1.20007(a)(14),

50 See ANSI/J-STD-025-A-2003, sec.  4.7.

51 Ballot Version of ANSI J-STD-025-B, secs. 3, 4.7 n.2 (June 2004) 
(emphasis added).

52 Third R&O at 16795 para. 1.

53 Id.

54 Third R&O at 19819 para. 55.  The Commission's conclusion was rooted in its
concerns about the technical mechanisms for providing the required 
capabilities to law
enforcement, rather than the required capabilities themselves. See 
id. at 16795 para. 1,
16819-20 paras. 55-56.

55 Id. at 16819 para 55.

56 Id. (emphasis added); see also id. at 16820 para. 56. TIA 
commenced work on the J-STD-
025-B packet data standard in direct response to the Commission's 
directive in the
Third R&O.

57 Third R&0 at 16795 para. 1,16819-20 paras. 55-56.

58 47 C.F.R. sec. 1.20007(b)(5).

59 Third R&O at 16835 para. 95.

60 Id. at 16795 para 1.

61 Id. at 16835 para 95.

62  The 200 millisecond time stamp requirement prescribed in the Third R&O (see
Third R&O at 16835-36 paras. 95-96) is reasonable for industry with 
respect to packet-mode
services because it already is included in various CALEA packet data 
standards (e.g.,
ANSI standard T1.678; ANSI standard T1.724; TIA Trial Use Version of 
and has been deployed by vendors and carriers. Moreover, several equipment
manufacturers have stated publicly that the 200 millisecond time 
stamp requirement is
feasible and provided by their equipment. There are also a number of 
protocols that
support time synchronization of up to one (1) millisecond, including 
the Network Time
Protocol (see IETF RFC 1305), Simple Network Time Protocol (see IETF 
RFC 2030), and
the Precise Time Protocol (PTP) (see IEEE 1588).

63 Since a time stamp indicates the date and time that an event is 
detected in the
network, the time stamp also should include the time zone offset from universal
coordinated time (UTC). A number of vendors already provide this 
feature as part of
the time stamp capability.

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