[This message was posted by Shahbaz Chaudhary of [email protected] <[email protected]> to the "General Q/A" discussion forum at http://fixprotocol.org/discuss/22. You can reply to it on-line at http://fixprotocol.org/discuss/read/b50c33e4 - PLEASE DO NOT REPLY BY MAIL.]
The FIX spec says that if checksum is wrong (and a host of other parsing problems), the message should be considered "garbled" and it should be quietly ignored (no rejects, no use of seqnos, no dropped connection). How are 'garbled' messages and framing errors handled in actual implementations used in the industry? Thanks > Typically, once a "framing error" is encountered, the session is > nonviable and should be disconnected and further Logon attempts should > be denied until manual intervention overrides this. > > The reason why the previous poster's suggestion of skipping forwards > until you see "8=FIX.4.4<soh>" is not viable is because you would > ultimately issue a ResendRequest for the missing messages and presumably > the garbage that you encountered before would be retransmitted to you > again. So you would end up with an endlessly repeating problem. > > So any "framing error" should be treated as a fatal error on the session > and it should be disconnected and disallowed pending manual > intervention. > > There are many types of framing errors: > 1. Message doesn't start with 8=FIX.4.4<soh> > 2. BodyLength doesn't immediately follow after BeginString or is > mal-formed. > 3. CheckSum field not where BodyLength value indicates it should be or > is mal-formed. > 4. Calculated checksum doesn't match CheckSum value. 5. BodyLength > longer than maximum allowed by FIX engine (I received one once that > indicated the mesage was more than 1 billion bytes long). I daresay > there are a few more I have omitted. > > I hope this helps. > > JohnP [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.
