We are an OMM/RFA consumer connecting to different TREP environments over time: LSEG-managed TREP, i

mktdata

We are an OMM/RFA consumer connecting to different TREP environments over time:
LSEG-managed TREP, internal bank ADS/ADH, and third-party MD ops infrastructure.

We understand that:

1. Dictionaries can be downloaded at runtime via MMT_DICTIONARY
   into memory from the ADS we are connected to.
2. Local text files (RDMFieldDictionary and enumtype.def) can be loaded as a
   FileDictionary fallback.
3. There is no supported API to reliably write a downloaded RDM dictionary back
   out as appendix_a / enumtype.def text files.
4. We do not have filesystem access to the ADS/ADH hosts.

Questions as Below:

1. What is the recommended production pattern to keep local RDMFieldDictionary
   and enumtype.def updated when the consumer may connect to different TREP
   sites, and host-level copy from ADS/ADH is not available?
2. Is runtime ChannelDictionary / network download considered the primary
   supported way to always match the encoding dictionary of the connected
   ADS, with local files only as a best-effort fallback?
3. For local file fallbacks, is the LSEG Real-Time / Template Service Pack
   (MyAccount) the official source for standard dictionaries? How should we
   confirm that a Service Pack revision matches the dictionary version
   advertised by a given ADS (directory / dictionary version fields)?
4. If a site uses custom (negative) FIDs, is the only supported way to obtain
   matching text dictionary files to request them from that site’s TREP
   administrators, or is there any other LSEG-supported distribution channel?

Jirapongse

@mktdata

Thank you for reaching out to us.

The recommended approach is to load dictionaries from the servers. To ensure seamless failover, all failover servers must provide identical dictionaries. Therefore, all servers within the same site must keep their dictionaries synchronized.

An alternative approach is to load dictionaries from the latest local dictionary files, which can be downloaded from the Software Download website. When using this approach, it is recommended to use the most recent dictionary files available. Whenever a new dictionary is released, all RTDS products are tested against it to ensure compatibility. You can verify the version of the loaded dictionary and use the latest available version.

Negative fields for custom dictionaries must be obtained from the respective providers. LSEG does not maintain custom dictionaries.