Subject: [Megaco] Syntax of MID

From: "Anand, Rashim" <[email-masked]>
Date: Thu, 25 Jul 2002 16:12:21 -0700

Hi,
   I am resending this mail to solicit comments.

Some time back we had a thread on MID being just a logical identifier going
on in the mailing list.
3015 Corr incorporates that concept (refer to section 8.3).

Shouldn't the ABNF and ASN definitions be modified to reflect that?
Currently, MID is
defined to be a choice of -

domain address / domain name / mtp address / device name

I think that MID could be better defined as -

mId = 1*( charsinMid )

charsinMid = ALPHA / DIGIT / ":" / "@" / "." / "[" / "]" /
                     "-" / ">" / "<" / "{" / "}" / "_" / "*" / "/" / "$"
    ;    basically the same characters which can be present in domain
name/address/mtp address/device name
    ;    some other characters could also be allowed

for ABNF and

      mId         OCTET STRING (SIZE(...)),

for ASN.

Such a modification would better reflect the logical identification purpose
of mid. The current
definitions IMPLICITLY restrict MID to domain name / address etc. This
restriction is inconsistent
with the nature of MID.

Based on above, serviceChangeMgcId and serviceChangeAddress (these are
currently of mId type) would have to be changed to something like -

serviceChangeAddress = ServiceChangeAddressToken EQUAL
                       ( ServiceChangeAddress / portNumber )
serviceChangeMgcId   = MgcIdToken EQUAL ServiceChangeAddress

ServiceChangeAddress = (( domainAddress / domainName )
                       [":" portNumber]) / mtpAddress / deviceName

for ABNF and something like -

serviceChangeMgcId  ServiceChangeAddress OPTIONAL,
in ServiceChangeParm with a comment - "the portNumber is not allowed
as a choice element in serviceChangeMgcId"
( the serviceChangeAddress parameter in contrast to the serviceChangeMgcId
  parameter can have just the portNumber )

for ASN.

Thank,
- Rashim

_______________________________________________
Megaco mailing list
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https://www1.ietf.org/mailman/listinfo/megaco

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From: Christian Groves <[email-masked]>
Date: Fri, 26 Jul 2002 14:55:34 +1000

Hello Rashim,

What is it that you want to do that the MID definition doesn't allow? People
have agreed that MID is logical but the current definition is rather flexible.
Device Name allows up to 64 characters. I do not see the point changing MID just
because people have agreed that its logical.

Regards, Christian

---

From: Christian Groves <[email-masked]>
Date: Fri, 26 Jul 2002 14:55:34 +1000

Hello Rashim,

Regards, Christian

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From: Troy Cauble <[email-masked]>
Date: Fri, 26 Jul 2002 18:46:31 -0400

>charsinMid = ALPHA / DIGIT / ":" / "@" / "." / "[" / "]" /

Specifying "anything goes here" doesn't really tell anyone what they need
to know.  It's a protocol hole.

Your proposal /*doesn't **actually say how to encode thing*s/ like
domain names, domain addresses, etc.

You'd need to add an explanatory paragraph that says "If it is a domain 
name,
use the 'domainName' production for the 'mId' element.", etc.  Ugly!  Or 
you'd
need to specify it in profiles!!  Much clearer to just keep

   mId                  = (( domainAddress / domainName )
                          [":" portNumber]) / mtpAddress / deviceName

If you really need the flexibility of "anything", it should be more like

   mId                  = (( domainAddress / domainName )
                          [":" portNumber]) / mtpAddress / deviceName / 
anythingMId

anythingMId    =  *some form distinguishable from the others (and from 
"portNumber")*

But, I'd propose waiting until another form is actually needed before 
doing something like this.

The arguments are similar for the ASN.1.  Don't remove the information 
needed to
communicate!

-troy

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From: Troy Cauble <[email-masked]>
Date: Fri, 26 Jul 2002 18:46:31 -0400

-troy