Transport

Things are going crazy in the immunization registry world. EHR vendors are now implementing HL7 messages and doing them quite well. Transport has now become the major issue. The CDC has not specified the method of sending HL7 data. The HL7 language was charted to specifically avoid transport issues and so this is left to each state and vendor to figure out. (Personally I would love to see a national standard, but there isn't one so we have to figure it out on our own.)

Here are the transport options I see being done right now:

File upload directly to registry
Users login to registry and upload HL7 files that have been exported.
Benefit: Easy for users to load data.
Drawback: Manual process that stops if the user forgets to load data.

File upload to secure FTP directory
User uses third-party application to load HL7 file into SFTP/FTPS location.
Benefit: fairly easy to setup.
Drawback: Normally a manual process, although it may be automated.

PHIN-MS
Sender and state install PHIN-MS and applications on both ends transfer file.
Benefit: PHIN-MS is free software provided by CDC.
Drawback: Not a simple application, takes a certain level of effort to install and configure. May not be supported on all platforms, or be accepted by all sending systems.

HTTPS method
Simple HTTPS method is used by several states and some EHR systems.
Benefit: Simple to implement by vendors so it can be automated.
Drawback: only limited supported in the industry.

Web Services method
Uses HTTPS.
Benefit: Industry standard and is fairly easy for EHR vendors to implement.
Drawback: There is not a standard web services definition that has been adopted by state registries so this still has to be negotiated with each vendor.

I personally like the simple HTTPS method, because, well it's simple. Besides that I think the Web Services is probably the best solution for the nation, if we can just get it standardized.