1 Storage Resource Management WG meeting, Sept Storage Resource Management: Functional and Operational Specifications September 14-15, 2005 Meeting at Jefferson Lab S torage R esource M anagement

2 Storage Resource Management WG meeting, Sept Functional Design Functional InterfaceOperational InterfaceLang. Interface Framework Framework Def. SRM Joint Functional Interface V1.0 SRM Joint Functional Interface V1.1 SRM Joint Functional Interface V2.0 SRM-WS Operational Interface V1.1 SRM-WS Operational Interface V2.1.1 SRM Joint Functional Interface V2.1 SRM-WS WSDL Interface V1.1 SRM-WS WSDL Interface V2.1.1 SRM Joint Functional Design V1.0 SRM Joint Functional Design V1.1 SRM Joint Functional Design V2.0 SRM Joint Functional Design V2.1 SRM Joint Functional Interface V2.1.1 SRM-CORBA Operational Interface V1.0 SRM-CORBA IDL Interface V SRM Joint Functional Interface V3.0 SRM Joint Functional Design V3.0 SRM-WS Operational Interface V3.0 SRM-WS WSDL Interface V3.0 SRM-WSRF Operational Interface V3.0 SRM-WSRF WSDL Interface V3.0 History of Functional and Operational SRM specifications

3 Storage Resource Management WG meeting, Sept Extending functions for advance features Issue: what to do in the case of functions that are in core, but are also used in advanced features with additional functionalityIssue: what to do in the case of functions that are in core, but are also used in advanced features with additional functionality E.g. Specifying a space- token for srmRemoteCopy when “space reservation” feature is supported. Solution: Extending parameters according to features f 1 (C) f 3 (C) f 7 (C) f 8 (C) f 4 (C)f 2 (C) f 5 (C) f 6 (C) f 1 (F 3 ) f 2 (F 3 ) CORE FEATURE 1 FEATURE 2 FEATURE 3 FEATURE 4 FEATURE 5 FEATURE 6 f 1 (F 3 ) f 2 (F 3 ) f 1 (F 1 ) f 2 (F 1 ) f 3 (F 1 ) f 1 (F 3 ) f 2 (F 3 ) f 3 (F 3 ) f 4 (F 3 )

4 Storage Resource Management WG meeting, Sept Expressing Overloaded Functions in Operational Spec Issue: given a core functionIssue: given a core function Some parameters are relevant only when some advanced feature is supported e.g. srmPrepareToGet: space_token only relevant when “space reservation” feature is supported Some parameters change what is valid with advanced feature e.g. srmPrepareToGet: SURL can be a directory if “directory” feature is supported Issue can come up with advanced function as wellIssue can come up with advanced function as well e.g. srmRemoteCopy: SURL can be a directory if “directory” feature is supported, and space token is valid only if “space management” feature is supported Possible solutionsPossible solutions Have a way for clients to know which parameter combinations to use Have explicit functions (i.e. methods, portTypes) for each combination

5 Storage Resource Management WG meeting, Sept Possible Solutions – pros and cons Feature Combinations Parameters P1 P2 P3 P4 P5 Function version Example: srmRm Core F(i)srmRm Space reservation F(i.1)srmRm.1 Remote access F(i.2)srmRm.2 Directory management F(i.3)srmRm.3 Core+ SR+RA F(i.4)srmRm.4 Core+ SR + DM F(i.5)srmRm.5 ……… Function F(i) Solution 1: Explicit Functions

6 Storage Resource Management WG meeting, Sept Possible Solutions – pros and cons Function Feature combination Method / portType srmRmCoresrmRm srmRm Space reservation srmRm.1 srmRm Remote access srmRm.2 srmRm Directory management srmRm.3 srmRm Core+ SR+RA srmRm.4 srmRm Core+ SR + DM srmRm.5 ……… srmLsCoresrmLs srmLs Space reservation srmLs.1 ……… Client needs to know which method to call for desired function Solution 1: Explicit Functions

7 Storage Resource Management WG meeting, Sept Possible Solutions – pros and cons FunctionFeatures Parameters vectors srmRmCore { } { } srmRm Space reservation { } { } srmRm Remote access { } { } srmRm Directory management { } { } ……… srmLsCore { } { } srmLs Space reservation { } { } ……… Client needs to know which parameters to use for desired function Solution 2: Overloaded Functions Note: Combination can be determined by AND’ing parameter vectors Therefore, there is no need for feature combinations

8 Storage Resource Management WG meeting, Sept Possible Solutions – pros and cons Both solutionsBoth solutions Clients need to know what to call, based on features supported Either which explicit method (e.g. srmRm.1, srmRm.2, etc) Or which parameters (e.g. p1, p2, p3, etc…) clients need to know when new features are added or changes made to parameters ButBut Solution 1 Requires new method variations when new features are added that effect a function Requires extensive changes to existing WS server and client that wishes to use the new feature Solution 2 Requires only new WSDL with minimal change on the server and client Can keep the specific method variations at the client API or command line and keep the SRM interface simple Easy transition from existing v Alternative to clientsAlternative to clients Multiple specialized (thinner) clients – not attractive solution 2 seems bettersolution 2 seems better