ITConnection::SetBandwidthInfo method

Article
03/22/2021

[ Rendezvous IP Telephony Conferencing controls and interfaces are not available for use in Windows Vista, Windows Server 2008, and subsequent versions of the operating system. The RTC Client API provides similar functionality.]

The SetBandwidthInfo method sets the bandwidth information.

Syntax

HRESULT SetBandwidthInfo(
  [in] BSTR   pModifier,
  [in] DOUBLE Bandwidth
);

Parameters

pModifier [in]: Pointer to a BSTR indicating the scope of the bandwidth being set. For more information, see the following Remarks section.
Bandwidth [in]: Bandwidth.

Return value

This method can return one of these values.

Value	Meaning
S_OK	Method succeeded.
E_INVALIDARG	The pModifier or Bandwidth parameter is not valid.
E_OUTOFMEMORY	Insufficient memory exists to perform the operation.
E_FAIL	Unspecified error.
E_NOTIMPL	This method is not yet implemented.

Remarks

The application must use SysAllocString to allocate memory for the pModifier parameter and use SysFreeString to free the memory when the variable is no longer needed.

Reference: RFC 2327.

The bandwidth modifier will normally be either CT or AS:

CT Conference Total: An implicit maximum bandwidth is associated with each time to live (TTL) on the Mbone or within a particular multicast administrative scope region (the Mbone bandwidth versus TTL limits are given in the MBone FAQ). If the bandwidth of a session or media in a session is different from the bandwidth implicit from the scope, a `b=CT:...' line should be supplied for the session giving the proposed upper limit to the bandwidth used. The primary purpose of this is to give an approximate idea as to whether two or more conferences can coexist simultaneously.

AS Application-Specific Maximum: The bandwidth is interpreted to be application-specific, i.e., will be the application's concept of maximum bandwidth. Normally this will coincide with what is set on the application's "maximum bandwidth" control, if applicable.

Note that CT gives a total bandwidth figure for all the media at all sites. AS gives a bandwidth figure for a single media at a single site, although there may be many sites sending simultaneously.

Extension Mechanism: Tool writers can define experimental bandwidth modifiers by prefixing their modifiers with "X-".

Requirements

Requirement	Value
TAPI version	Requires TAPI 3.0 or later
Header	Sdpblb.h
Library	Uuid.lib
DLL	Sdpblb.dll

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