Hi,
EBIF I04 Spec (Section 9.6.9.15) states as follows

####Start####
A channel map identifier environment property reference is used to obtain information about the current channel
map from the platform.
Enhanced TV Binary Interchange Format 1.0 OC-SP-ETV-BIF1.0-I04-070921
9/21/07 CableLabs® 89
A channel map identifier environment property SHALL dereference an integer value in the range [-1,65535] whose
value is derived from Service Information (SI), and whose value is the current channel map identifier. If no channel
map identifier is known, then it SHALL dereference to minus one (-1).
For a channel map identifier environment property (15), the special environment property’s operand bytes SHALL
adhere to the syntax specified by Table 29 - Environment Property Reference Format 2.
Note: This specification does not define the value space of channel map identifiers. Interoperable uses of a
channel map identifier must profile this specification to elaborate the definition of this value space.
####End####

QUERY ONE
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Does OCAP (1.0-I16-050803) have any API which can be used to fetch the current VCT ID (Virtual channel table id) ? OR Should we add a separate Section Filter for loading VCT Section?

QUERY TWO
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SCTE SPIP Spec (ANSI/SCTE 142 2009) (http://www.scte.org/documents/pdf/Standards/ANSI_SCTE%20142%202009.pdf) references ATSC PSIP A/65A Spec for defining VCT formats - Revision C of ATSC PSIP A/65 spec is available at http://www.atsc.org/standards/a_65cr1_with_amend_1.pdf (See section 6.3) - CVCT is defined as follows

1. The Cable Virtual Channel Table is carried in private sections with table_id 0xC9

2. PID for Cable VCT shall have the value 0x1FFB (base_PID)

3. “transport_scrambling_control” bits shall have the value ‘00’

4. “adaptation_field_control” bits shall have the value ‘01’

5. “current_next_indicator” is a one-bit indicator present in CVCT, which when set to ‘1’ indicates that the Virtual Channel Table sent is currently applicable. When the bit is set to ‘0’, it indicates that the table sent is not yet applicable and shall be the next table to become valid. This standard imposes no requirement that “next” tables (those with current_next_indicator set to ‘0’) must be sent. An update to the currently applicable table shall be signaled by incrementing the version_number field. Informative

Note: It is inadvisable to deliver “next” tables far in advance of their use, because the complexity of the process necessary to make a change to either current or next is significantly increased. Transmission of a “next” table may be helpful when the table is so large it requires multiple sections for delivery. For tables small enough to fit into one section, use of “next” tables is deprecated (strongly discouraged).

6. “version_number” — This 5 bit field is the version number of the Virtual Channel Table (VCT). For current VCT (current_next_indicator = ‘1’), the version number shall be incremented whenever the definition of the current VCT changes. Upon reaching the value 31, it wraps around to 0. For the next VCT (current_next_indicator = ‘0’), the version number shall be unit more than that of the current VCT (also in modulo 32 arithmetic). In any case, the value of the version_number shall be identical to that of the corresponding entries in the MGT.

CVCT ID will be constant (0xC9), so the unique CVCT IDENTIFIER means a combination of “version_number” and “table_id” or “version_number” alone? OR is it something totally different from my understanding?

Thanks and regards,
ronish