Wireshark-dev: Re: [Wireshark-dev] Subdissector with multiple selection fields needed?
From: Weston Schmidt <[email protected]>
Date: Tue, 13 Jul 2010 10:10:15 -0700
On Mon, 2010-07-12 at 22:19 -0700, Guy Harris wrote:
An "ETV integrated signaling stream", as per CableLabs spec OC-SP-ETV-AM1.0-I04-070921?
This is one of the two specs.  The other spec is SP-ETV-BIF1.0-IO4-070921 which defines the trigger, and trigger handler.

> trigger_table_id (2 bytes)

So which field is that?  The ETSI spec doesn't seem to have anything of that sort, and the only 16-bit field in an EISS section, according to the CableLabs spec, is the application_type field.  Is this from some other spec?
Yes, the SP-ETV-BIF1.0 spec is the widget/data/presentation based specification.  Now that you asked the question, it got me wondering if I should refactor my code into 2 layers (though I'll still have this issue).
At least for the organization ID/application ID pair, that's somewhat similar to an OID and protocol ID in the SNAP protocol, which we handle by having the OID select a dissector table from a table-of-dissector-tables, and using the protocol ID to select a dissector from the dissector table in question.  I don't know whether that would work here or not.

However, I'm not sure how the trigger table ID would fit in there, other than just adding another layer to the tables-of-tables.
Thanks for the suggestion on where to look for code that does something similar.  I think you're right that the table ID will end up simply being another table-of-tables as well.