[cisco-voip] Display IE & CCM

[Andre Beck]

Hi Wes,

On Sat, Jan 07, 2006 at 05:07:05PM -0500, Wes Sisk wrote:
> 
> Usually CM will pass information included in the DisplayIE to phone  
> sets.

I know this works with Display IEs that are part of a SETUP. But will it
work when they are part of an INFORMATION message that comes along in the
middle of a call?

> Can you send me a complete CCM trace?

I'll have to figure out how to do this first ;)

What I've found out so far is the gateway (IOS 12.4(3b)) does forward the
messages to the CCM via H.323, it even does forward the NOTIFY with the
AOCD/E. But while, in a SETUP coming from CCM towards the gateway, the
Display IE is explicitely encoded as such, in the messages from the
gateway to CCM it is hidden in the UU data:

H.323 <--
   Q931 Message IE Decodes
 Protocol Discriminator : 0x08
 CRV Length             : 2
 CRV Value              : 0x015D
 Message Type           : 0x05: SETUP
  Bearer Capability: Length Of IE=3
  Data 8090A2
  Display: Length Of IE=10
  Data 416E6472E9204265636B
  Calling Party Number: Length Of IE=4
  Data 00813331
  Called Party Number: Length Of IE=9
  Data 803034373136343636
  User-User: Length Of IE=112
  Data 0520B0060008914A00020140090041006E0064007200E90020004200650063006B020001038037A497990000A71489259FB11D5D010000C0A86F1F00450C0700C0A86F0106B8110000A71489259FB11D5D010000C0A86F1F010001000AA001000F0140B50000120880A4000400010100

Note that in this H.225/Q.931 SETUP, there is a Display IE containing my
name, but:

ISDN <--
 ISDN BR1/2 Q931: RX <- INFORMATION pd = 8  callref = 0xC6 
        Display i = '2 Einheiten'

H.323 -->
  Q931 Message IE Decodes
 Protocol Discriminator : 0x08
 CRV Length             : 2
 CRV Value              : 0x815D
 Message Type           : 0x7B: INFORMATION
  Called Party Number: Length Of IE=1
  Data 91
  User-User: Length Of IE=62
  Data 052480060008914A00040B00110000A71489259FB11D5D010000C0A86F1F10A001001B0140B5000012146001010001280D280B322045696E68656974656E

Here the generated H.323 message does no longer bear a Display IE. The
information is, however, included in the UU data, just have a closer
look on the 322045696E68656974656E the message is ending in.

So I'm sure the message is relayed to CCM, but I neither know whether it
is in a format that CCM understands nor whether CCM is supposed to display
it to the phone at all (it beeing an INFORMATION message, no SETUP).

I'll go and collect some experience with CCM tracing.

TIA,
Andre.
-- 
                  The _S_anta _C_laus _O_peration
  or "how to turn a complete illusion into a neverending money source"

-> Andre Beck    +++ ABP-RIPE +++    IBH Prof. Dr. Horn GmbH, Dresden <-