Space Link Extension - Service Management - CCSDS

DRAFT RECOMMENDED STANDARD FOR SPACE LINK EXTENSION SERVICE MANAGEMENT
NOTE – The Sender process that generates the message set is external to (that is, not a
part of) the SLE-SM document exchange protocol.
Each message in a message set is given a messageSequenceNumber. For invocation
messages, the messageSequenceNumber indicates the order in which the messages are
to be processed by the Receiver. A Sender application process that requires invocation
messages to be processed by the Receiver in a certain sequence must order the message-
SequenceNumbers of the message in the desired order. For other message types (returns,
notifications, and confirmations), the messageSequenceNumber indicates the order in
which the messages are created.
Message sets containing multiple messages may only be created for the transmission of
invocation messages. The other message types (returns, notifications, and confirmations)
shall be sent individually in separate message sets.
3.3.2.3 Receiver Receives and Validates SLE-SM Message Set
Upon receipt of a document via the Receiver’s SLE-SM message set port, the Receiver shall
perform message set validation. Message set validation consists of several validation steps
(syntactic, authorization, sequencing of invocation messages within the message set, and
verification of support for the invoked operation), some of which are performed only when
certain message types are contained in the message set. These validation steps are described
in subsequent paragraphs.
Syntactic validation. The Receiver shall perform syntactic validation of the document to
ensure that the document is a properly formatted SLE-SM message set of a version that is
supported by the Receiver. If the Receiver cannot syntactically validate the message set, the
Receiver shall generate and send an UnrecognizedMessageSetResponse exception
response to the exception response port of the Sender, after which the Receiver has no further
obligation for interpreting and acting upon the document.
Authorization validation. Once the received document has been validated as a syntactically
correct message set, the Receiver shall perform authorization validation of the message set to
ensure (a) that the communication service-provided identifier of the Source of the message
set is authorized to use the sleSmCreatorName (see table 3-3) contained in the message
set, (b) that the Service Agreement identified by the serviceAgreementRef (table 3-3)
in the message set is supported by the Receiver, and (c) that the sleSmCreatorName in
the message set is authorized to send messages in the context of the Service Agreement
identified by the serviceAgreementRef in the message set. If the Receiver is unable to
validate the authorization of the Sender of the message set, the Receiver shall send an
UnrecognizedMessageSetResponse exception response with appropriate diagnostic
information (as specified in table 3-23) to the exception response port of the Sender, after
which the Receiver has no further obligation for interpreting and acting upon the message
set.
CCSDS 910.11-R-2 Page 3-6 March 2008