[This message was posted by Darshan Khedekar of <[email protected]> to the "FAST Protocol" discussion forum at http://fixprotocol.org/discuss/46. You can reply to it on-line at http://fixprotocol.org/discuss/read/7b1fdeea - PLEASE DO NOT REPLY BY MAIL.]
Hi Nathan, There is no defined constraint on the operators defined for a "field" in FAST1.1. FAST is all about compression and squeezing that extra bit of business information in a network message. Eurex EnBS took a pragmatic approach for applying operators to fields. Take for instance your example for "prodId". The Product Reference Message the prodId follows the copy operator and for the Single Leg Reference it follows copy operator. The reason being there is only one message for product in "product reference" and many single leg instruments per product in "single leg reference" message. This ensures that the complexity of processing due to FAST operators is balanced by the actual compression of the data. To reiterate FAST protocol leaves it to the application designer to use the power of FAST as per the application requirements and does not put any constraints on the field operator associations. Hope I am clear. I would support option 1 from your suggestions below. Regards, > Hi, > > I'm currently working on a port of our C++ decoder from CME FAST to > Eurex EBS. There appears to be something different happening with the > default key names for the Eurex global dictionary. > > Multiple EBS templates contain the same field, for example "prodId". > However, different templates are applying different operators to this > key - sometimes its DEFAULT, sometimes NOOP, sometimes COPY, etc, all > for the same prodId string field. > > Our dictionaries aren't currently implemented to allow a change of > operator for a key after it is initially contructed. > > Before I start making tweaks, I was hopeing someone could verify which > of the following is the correct solution: > > 1) Allow different operators to be applied to the same key and previous > value as retrieved from the dictionary. > > 2) Append the operator to my keyname, (so key becomes "prodId_copy" for > example), and thereby each key maintains the current implementation > where one key can only have one operator applied to it. > > 2) Something different :) > > Many thanks in advance for any advice! > > Cheers, Nathan [You can unsubscribe from this discussion group by sending a message to mailto:[email protected]] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Financial Information eXchange" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/FIX-Protocol?hl=en -~----------~----~----~----~------~----~------~--~---
