Bionic Buffalo Tech Note #103: Introduction to Pegasus Client Support
In contrast, in the Pegasus model, all of the objects are on the server. The Pegasus ISA defines three
main classes relating to sessions and connection:
SessionModule::Session
,
SessionModule::SessionGateway
, and
ServiceGatewayModule::ServiceGateway
(which inherits
DSM::SessionUU
). It also defines the DSM-CC Client, a component on the client
system. In the Pegasus model, to establish a session with a server, the client application calls an
uspecified API of the DSM-CC Client component. The DSM-CC Client component sends the U-N
SessionSetup message to the SRM. The SRM negotiates with the server's
SessionModule::
SessionGateway
object. The
SessionModule::SessionGateway
object creates a
SessionModule::Session
object, which represents the session. The
SessionModule::
SessionGateway
attaches to a
ServiceGatewayModule::ServiceGateway
object on
behalf of the client and the session. Unlike a DSM-CC ServiceGateway, a Pegasus ServiceGateway
doesn't allow the client to browse the server for content. Indeed, it inherits
DSM::SessionUU
, but
not any directory operations, so it is merely vestigial with respect to its DSM-CC counterpart.
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DSM::Session
DSM::SessionSI
DSM::
ServiceGateway
DSM::
ServiceGatewayUU
client application
attach
attach
directory operations
(list, resolve, get, etc)
Client
directory operations
(list, resolve, get, etc)
Server
User-User/IIOP
protocol
class interactions
in systems without
User-Network
protocol
attach
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