Questions on the Application interface with the SDP layer
Original Post: Registration of Application with SDP (Fragmentation of Packet)
(eGroups Msg. ) Date: 2000-12-15
In the SDP spec very little given about the registration of an
application with the SDP Server. This is because how you implement the interface between
the app and the SDP is totally up to the developer. Some typical questions are:
Question 1
When does the application actually register itself with the SDP.
Answer 1
Anytime. One typical SDP implementation (the Digianswer implementation SDP) exports an
API that can be called by applications at any time. You could for instance
"register" when you want to expose a service to remote devices.
Question 2
What is the information given by the Application to the SDP.
Answer 2
Applications use the API to "register" services (service records) in the
local data base - this is just one example.
Question 3
In what format is it given? Is it in the format of a data element as defined in SDP or
a application format. If not then in what format is the information given
Answer 3
The Digianswer SDP exports a few APIs needed for database handling (such as
CreateRecord, AddAttribute and so on), a few APIs for "connecting" SDP protocols
and sending SDP requests. The actual format used is implementation specific.
Question 4
When a application adds or modifies the database it talks to the SDP with a
ServiceRecordHandle. Is this right?
Answer 4
That is up to the developer but a service record handle is a good "record
identifier". The Digianswer CreateRecord API creates an (almost) empty service record
and then returns the service record handle to the caller. The caller can then add
attribute (or delete stuff) to this specific record.
|
