Subject: Final Issue Scorecard

From: Tom-PT Taylor <[email-masked]>
Date: Fri, 4 Feb 2000 02:26:47 -0600

My submissions to the ITU will be based on the contents of this note.  If
something is really wrong, we can take a verbal message to Geneva when the
errata are dealt with next Tuesday.  (Clarifications can be fixed up over
the next week -- they are slightly less urgent.)  There are still a number
of open issues, but in my judgement we don't have to settle them to have a
working protocol.

Errata (intended for incorporation into H.248 before publication)
=============================================

Section affected: 7.1.6
Erratum: first paragraph, last sentence: replace with "A stream is deleted
by setting empty Local and Remote descriptors for the stream with Reserve in
LocalControl set to "false" on all terminations in the context which
previously supported that stream."
Reference: Chip Sharp, 25/01/00 and Tom Taylor, 02/02/00, Cisco SG16:
Streams

Section affected: 7.1.7
Erratum: second paragraph, first sentence.  Remove "delete" as an allowed
value for the Mode parameter.  Remove the final sentence of that paragraph.
Reference: Chip Sharp, 25/01/00 and Tom Taylor, 02/02/00, Cisco SG16:
Streams

Section affected: 7.1.14.

Erratum: paragraph explaining timer rules, beginning "The collection of
digits according to a Digit Map may be protected by three timers ...",
modify rule 3 concerning the use of the short timer (S) to read as follows:
"3.   If the digit string has matched one of the patterns in the digit map,
but it is possible that more digits could be received which would cause a
match with a different pattern, then instead of reporting the match
immediately, the MG must apply the short timer (S) and wait for more
digits."
Reference: Tom Taylor, 03/02/00, More Digit Map Fixes

Erratum: paragraph explaining event symbols, beginning "The formal syntax of
the digit map ...":  add the following sentence at the end of this
paragraph:
"Finally, the dot symbol "." stands for repetition of the symbol which
precedes it an arbitrary number of times."
Reference: Tom Taylor, 03/02/00, More Digit Map Fixes

Erratum: paragraph beginning "In addition to these event symbols, the string
may contain ..."
The "S" duration modifier is unexplained and should be deleted.

Erratum: replace the numbered steps from 3 onwards in the description of
processing behaviour near the end of the section with the following:

"3.   If the result does not match any entry and is under-qualified
(partially matches at least one entry in the DigitMap), do nothing further.

"4.   If the result is a match and is under-qualified (partially matches at
least one other entry in the DigitMap), apply the short timer and await
further
digits. If the timer expires and no digits are received or an end-of-dialing

indication is received, send the current dial string to the MGC.  If one or
more digits are received apply steps 1 through 5 again.

"5.   If the result is a match and is over-qualified (i.e., no further
digits could possibly produce a match), send the current dial string to the
MGC using the completion event defined in the package whose events are being
mapped into the digit map string."

Reference: Selvam Rengasami, 27/01/00, Telcordia SG 16: Comments on 7.1.13
on DigitMaps in H.248

Erratum: example at end of section.  The "L" and "S" modifiers should be
deleted.  The "*" and "#" symbols should instead be "E" and "F" in
accordance with the mapping in the DTMF detection event package (see erratum
for section E.6).

Section affected: 7.2.5
Erratum: third sentence before table at end, replace "unspecified" with
"wildcarded".
References:
Raised: Madhu Babu, 14/01/00, "unspecified" Context Identifier for Audit
Command
also Selvam Rengaswami, 27/01/00, Telcordia SG16: Comments on 8.1.2
regarding ContextIDs in H.2 48
Fix per Brian Rosen, 14/01/00, "unspecified" Context Identifier for Audit
Command

Section affected: 7.2.8

Erratum: API should show ServiceChangeDescriptor as input,
ServiceChangeReplyDescriptor as output.  It should show TerminationID as
non-optional output.
Reference: Sachin Mittal, 02/02/00, Command API

Erratum: in the bulleted list of contents of the ServiceChangeDescriptor,
use "ServiceChangeProfile" instead of "Profile", "ServiceChangeVersion"
instead of "Version", and "ServiceChangeMgcId" instead of "MGCIdToTry".
Make similar changes as required throughout the section.  Add the
"Extension" field.

Erratum: in the explanation of ServiceChangeMethod values, following item
(6) Failover, add another item as follows:

"(7) Another value whose meaning is mutually understood between the MGC and
the MG."

Erratum: to the paragraph beginning "The optional ServiceChangeAddress
parameter ...", add the following sentence:
"The ServiceChangeAddress and ServiceChangeMgcId parameters are mutually
exclusive."
Reference: Chuong Nguyen, 02/02/00, ServiceChange Method handoff

Erratum: following the paragraph beginning "The optional Timestamp parameter
specifies ...", add a new paragraph as follows:

"The optional Extension parameter may contain any value whose meaning is
mutually understood between the MGC and the MG."

Reference: Chuong Nguyen, 02/02/00, ServiceChange

Erratum: Delete the phrase "Summarizing use of properties in the
ServiceChange Descriptor:" and the bullets which follow -- they are partly
misleading and partly repetitious.
Reference: Chuong Nguyen, 31/01/00, ServiceChangeAddress; Chip Sharp,
04/02/00, Cisco SG16: Service Change

Erratum: paragraph following the last such bullet, beginning "The return
from ServiceChange ...": replace with the following:

"The return from ServiceChange is empty except when the Root terminationID
is used.  In that case it includes the following parameters as required:
*       ServiceChangeAddress, if the responding MGC wishes to specify an new
destination for messages from the MG for the remainder of the association;
*       ServiceChangeMgcId, if the responding MGC does not wish to sustain
an association with the MG;
*       ServiceChangeProfile, if the responder wishes to negotiate the
profile to be used for the association;
*       ServiceChangeVersion, if the responder wishes to negotiate the
version of the protocol to be used for the association.

Reference: Chuong Nguyen, 02/02/00, ServiceChange

Section affected: 8
Erratum: Fourth paragraph after figure: delete first sentence -- second
sentence says what must be said.

Section affected: 8.3

Erratum: second paragraph.  Delete reference to RFC 2145.  Add version
number for current version.  Hence the second sentence should now read:
"Versions consist of one or two digits, beginning with version 1 for the
initially-decided version of H.248."
Reference: Jo Friedman, 24/01/00, Question about Protocol Version

Section affected: 9.
Erratum: in second paragraph, where IP ports are specified: expect to obtain
the same value of port number for both TCP and UDP, but a different set of
ports for text vs. binary operation.
Raised: Christian Huitema, 14/01/00, FW: Application for port-number
Status: Chair has applied for second pair of port numbers for binary
operation.  Assigned port numbers should be known before decision of H.248.

Section affected: 11.1
Erratum: final paragraph: delete final sentence, which currently states
"ServiceChange may only be applied to the Root by Master MGC".
Reference: Chip Sharp, 25/01/00, Cisco SG16: Virtual MG & Root

Section affected: Annex A, section A.2

Erratum: delete OPTIONAL for the auditDescriptor term in the AuditRequest
production.
Reference: Sachin Mittal, 31/01/00, v 14: Change required in Audit command
description

Erratum: remove delete (5) from the StreamMode production.
Reference: Chip Sharp, 25/01/00 and Tom Taylor, 02/02/00, Cisco SG16:
Streams

Erratum: modify the comment after PkgdName to say that wildcarding of
Package Name (first two octets) is permitted only if Property Name is also
wildcarded.
Reference: Tom Taylor, 01/02/00, Meaning of Wildcarded PackageID

Section affected: 12.1.1
Erratum: in the explanation following "PackageID", delete all after "Is an
identifier"
Reference: Tom Taylor, 02/02/00, Text PackageIDs

Section affected: Annex A, section A.3
Erratum: in production "digitLetter", "ditigMapLetter" should be replaced by
"digitMapLetter".
Erratum: in accordance with section 7.1.14, the production "digitMapLetter"
should include the following symbols only: "0" through "9", "A" through "K",
and the long duration modifier "L".  Production MFsig should be deleted.

Section affected: Annex B, section B.2

Erratum: delete OPTIONAL for the auditDescriptor term in the AuditRequest
production.
Reference: Sachin Mittal, 31/01/00, v 14: Change required in Audit command
description

Erratum: modify production ErrorCode to be 1*4(DIGIT)
Reference: Paul Rupsis, 03/02/00, More IANA Considerations

Erratum: remove DeleteToken from the production streamModes and from the
list of tokens.
Reference: Chip Sharp, 25/01/00 and Tom Taylor, 02/02/00, Cisco SG16:
Streams

Erratum: modify the production pkgdName to exclude the combination "*/"
ItemID
Reference: Tom Taylor, 01/02/00, Meaning of Wildcarded PackageID

Erratum: in accordance with section 7.1.14, the production "digitMapLetter"
should include the following symbols only: "0" through "9", "A" through "K",
and the long duration modifier "L".  Production MFsig should be deleted.

Erratum: the range 1*64 in the productions quotedString and VALUE should be
replaced by 1* (i.e. one or more characters).
Reference: Steve Magnell, 02/02/00, maximum size of a VALUE

Section affected: Annex D, section D.1.1
Erratum: in the second paragraph, second sentence, replace the phrase "from
the same entity" with the phrase "to the same entity (same mId)".  In the
final sentence, replace the clause "which is simply ignored" with the clause
"but a TransactionPending response is generated".
Reference: Chip Sharp, 04/02/00, Cisco SG16: Transaction ID uniqueness

Section affected: Annex E, section E.5.3
Erratum: event name d* is not a legal production, and should be changed to
ds ("s" for "star").  Similarly, event name d# should become do ("o" for
"octothorpe").
Reference: Tom Taylor, 27/01/00, Cisco SG16: Comment on E.3.4

Section affected: Annex E, section E.6
Erratum: delete the final sentence.  This removes the option not to support
some tones.
Reference: Chip Sharp, 25/01/00, Cisco SG16: Annex E Comments

Section affected: Annex E, section E.6.2

Erratum: modify the definition of the DigitMap Completion Event to read as
follows:

DigitMap Completion Event
EventID: ce, 0x0001
Raised when pattern match or timeout is detected on a digit map.
EventsDescriptor parameters: none
ObservedEventsDescriptor parameters:
        DigitString
                ParameterID: ds (0x0001)
                Type: string of digit map symbols (possibly empty)
                Possible values: any sequence of the characters "0" through
                 "9", "A" through "F", and the long duration modifier "L".
                Description: the actual sequence of observed events,
                represented by their corresponding digit map symbols, which
                matched part or all of a digit map string.
        Extras
                ParameterID: ex (0x0002)
                Type:  list of toneIDs
                Possible values: any of the DTMF toneIDs defined in the
                table in section E.5.3
                Description: the sequence of tone events detected in the
                interval subsequent to completion of the (sub)string
reported
                in DigitString and before initial, long, or short timer
expiry as
                applicable.
        Completion
                ParameterID: cm (0x0002)
                Type: enumeration
                Possible values: "M" (unambiguous match), "S" (short timer
                expiry), or "T" (initial or long timer expiry)
Reference: Tom Taylor, 03/02/00, More Digit Map Fixes

Erratum: include the following text and table to provide mapping between
DTMF events and digit map symbols:

"The following table maps DTMF events to digit map symbols, for use as
described in section 7.1.14:"

    DTMF Event     Digit Map
                    Symbol
    d0 (0x0010)       "0"
    d1 (0x0011)       "1"
    d2 (0x0012)       "2"
    ...               ...
    d9 (0x0019)       "9"
    da (0x001a)       "A"
    db (0x001b)       "B"
    dc (0x001c)       "C"
    dd (0x001d)       "D"
    ds (0x0020)       "E"
    do (0x0021)       "F"

Reference: Chip Sharp, 25/01/00 and Tom Taylor, 27/01/00, Cisco SG16:
Comment on E.3.4

Erratum: delete reference to MF digits in the list of possible values.  The
latter must be defined in a separate package.

Section affected: Annex E, section E.9.2

Erratum: add the following behavioural description to the "onhook" event:
"If the first event descriptor after (re)establishment of MGC control over
the specific termination concerned or the MG as a whole contains the on-hook
event request and the line is already on-hook, the MG shall act as if
on-hook had occurred immediately after the event descriptor became active."
Erratum: add the following behavioural description to the "offhook" event:
"If the first event descriptor after (re)establishment of MGC control over
the specific termination concerned or the MG as a whole contains the
oof-hook event request and the line is already off-hook, the MG shall act as
if off-hook had occurred immediately after the event descriptor became
active."
Reference: Brian Rosen, 21/01/00, and subsequent discussion in the
Preconditions thread, resolved by Tom Taylor, 25/01/00.

Section affected: Annex E, section E.10.3
Erratum: for the test type parameter, "Possible values": insert the comment
"(extendible)" after "q724"

Section affected: Annex E, section E.10.5
Erratum:  replace all after "... perform the test in accordance with ..." by
the clause:
 "... the specified test type and information provisioned in the MG for the
affected termination."
Reference: Chip Sharp, 25/01/00 and Tom Taylor, 02/02/00, Cisco SG16: Annex
E Comments

Section affected: Annex E, section E.11.1
Erratum: add the following property:
Silence Suppression
   PropertyID: ssup (0x1008)
   This property indicates whether silence suppression is to be activated in
the encoding of the audio media flow to which it relates,
   Type: Boolean
   Possible values: True if silence suppression is to be applied.
   Defined in: LocalControl
   Characteristics: read/write
Reference: Chip Sharp, 25/01/00, Cisco SG16: Annex E Comments

Section affected: Annex E, section E.13.1
Erratum: modify the definition of the Echo Cancellation property to readf as
follows:

Echo Cancellation
                PropertyID: ec (0x0008)
                By default, the telephony gateways always perform echo
cancellation according to
                G.165/G.168. However, it is necessary, for some calls, to
turn off these operations.
                Type: enumerated
                Possible Values:
                                "on" (when the echo cancellation is
permanently enabled and will disregard any
                                incoming tones)
                                "g165" (when ec is according to G.165/G.168:
ec is on, but will turn
                                itself off when it sees a 2100Hz tone with
phase reversal (i.e. a CED fax tone, or an
                                ANS modem tone)
                                "g164" (when ec is according to G.164)
                                "off" (when it is turned off.)
                                The default is "g165".
        Defined In: LocalControlDescriptor
        Characteristics: read/write

Reference: Nancy Greene, 03/02/00, E.13.1 echo cancellation

Section affected: Appendix A, section A.1.2

Erratum: step 9, remove "L"and "S" characters from the digit map.  Use "E"
instead of "*" and "F" instead of "#".

Erratum: step 11, parameters to dd/ce event should be
"{ds="916135551212",cm=M}"
Reference: Tom Taylor, 03/02/00, More Digit Map Fixes

Erratum: step 15, add the line "Events = 1234{al/of}" preceding the Signals
line.
Erratum: step 16.  Insert the line "Add = A5555{}" above the line "Add =
A5556{"
Reference: Ameneh Zahir-Emami, 02/02/00, some comments on Appendix A of
megaco : Example call flows

Clarifications (intended for the H.248 Implementor's Guide)
==========================================

Section affected: 7.1.5

Comment: if a command other than ServiceChange or Subtract is received for a
terminationID which is in Test or Out of service state, the MG should reject
the command with error 503 - Service unavailable.
Reference: Sachin Mittal, 31/01/00, ServiceChange

Section affected: 7.1.14

Comment: the events which are being mapped into a digit map descriptor are
recognized as individual events as they are detected.  In particular,
regardless of the status of matching of the digit map, event detection will
stop emission of signals in progress unless the KeepAlive parameter is set.
Reference: Madhu Babu, 25/01/00 and subsequent discussion, Stopping of Dial
tone

Comment: when an event descriptor causing digit map accumulation is replaced
by an embedded event descriptor, the current dial string must be cleared and
the status of matching of the digit map must be reset.
Reference: Chip Sharp, 25/01/00, Embedded Events/Signals Descriptor

Section affected: 7.2.8

Comment: Where the terminationID designates an individual termination the
sender of the ServiceChange command should use the contextID of the context
in which the termination currently lies.  In any other usage the contextID
has no significance for the processing of the ServiceChange command.
Reference: Sachin Mittal, 27/01/00 and Tom Taylor, 31/01/00, Importance of
ContextID in ServiceChange command

Comment: If a termination is already in the Null context when a Graceful
ServiceChange is issued/received, the serviceState must be set to "out of
service" as soon as the delay has expired, or immediately if the delay is
null.
Reference: Sachin Mittal, 27/01/00, ServiceChange in Null context

Comment: If the MGC issues a ServiceChange (restart) for a termination and
it can be recovered (i.e. hasn't lost its bearer), the MG must act on the
command.  If the termination cannot be recovered the MG must reject the
command with error return.
Reference: Madhu Babu, 27/01/00 and Tom Taylor, 28/01/00, ServiceChange

Comment: Profile versions are unrelated to versions of the protocol.
Reference: Chuong Nguyen, 02/02/00, ServiceChange

Comment: for transport over TCP or UDP, the MG should not include a
ServiceChangeAddress parameter in the command.  The MGC should send its
messages to the address/port which was the source of the message containing
the ServiceChange command.
Reference: Chuong Nguyen, 02/02/00, ServiceChange and earlier threads.

Section affected: 8
Comment: in final paragraph, failure of the application-level timer should
be notified to local management, since it indicates a potential failure of
the peer application.  Local management may decide to initiate an alternate
association.

Section affected: 8.1.1
Comment: the use of sequential transactionIDs simplifies detection of
duplicate transactions.

Tom Taylor
Advisor -- Emerging Carrier IP Standards
E-mail: [email-masked] (internally, Tom-PT Taylor)
Phone and FAX: +1 613 736 0961