1
The Gateway System 2
Overview 3
Goals 4
Seamless Access 5
Three-Tier Architecture 6
Towards a complete solution ... 7
PSE Example: CCM 8
Target Architecture 9
Design Issues 10
Gateway Implementation 11
Gateway Implementation (2) 12
Gateway Implementation (3) 13
Gateway Implementation (4) 14
Front End 15
CTA specific knowledge database 16
Visual Authoring Tools 17
Example: Data Flow 18
Example: DARP 19
User and Group Profile 20
Resource Identification and Access 21
Visualizations, Collaboration, ... 22
Front-End infrastructure 23
Front-End Support 24
Portal Page 25
User Context 26
Gateway Initial Page 27
Control Applet 28
Screen Dump of the Control Applet 29
Navigator 30
CCM PSE Invoked from Gateway 31
Problem description toolboxes 32
Code toolboxes 33
Resource Request Toolbox 34
Other toolboxes 35
Middle-Tier 36
WebFlow Server 37
CORBA Based Middle-Tier 38
WebFlow Context Hierarchy 39
Middle-Tier modules serve as proxies of Back-End Services 40
Back End 41
Back End Services 42
WebFlow over Globus 43
How to add new Back-End hardware resources 44
Gateway Security 45
Security Model (Keberos) 46
Building Gateway Components 47
Middle-Tier is given by a mesh of WebFlow Servers that manage and coordinate distributed computation 48
How to develop a Gateway component (or a toolbox) 49
What does it take to convert a legacy (high performance) application into a Gateway Back-End service? 50
How the Back-End interacts with the rest of the system? 51
Implementing Back-End Services 52
What does it take to develop a Gateway module (a proxy)? 53
Example of IDL definition 54
Module functionality 55
Event binding 56
Front-End controls 57
Controlling a module 58
Selecting a Predefined Task 59
Visual Authoring Tools
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