Re: [wsrm] time management: the options

From
John Fuller <>
Date
2003-11-07T12:39:15+00:00
ID
Thread
Re: [wsrm] time management: the options
can XACML help at the granularity of endpoint-policy?

On Nov 7, 2003, at 1:23 AM, Jacques Durand wrote:

Here is a summary of the two major options I believe we face about dealing with timing, as outlined in previous mails, 

and my analysis of their advantages / disadvantages. 

After consideration, I personally favor Proposal #1 (the one we started on at f-2-f). 

Tomorrow I will map this time management proposal to our list of current issues, 

and propose corresponding resolution/impact to several of them. 

The schema so far is same as last proposed in f-2-f. 

Jacques 

Proposal #1: (use time parameters) 

----------- 

Uses ExpiryTime, GroupExpiryTime, MaxGroupIdleTime, here carried in the protocol 

(messages), as discussed last f-2-f. 

The group termination follows rules based on these values, as we outlined them 

in f-2-f, and of which I propose/summarize a complete version in draft sent out Nov 2. 

Advantage: 

- group duration, scope of duplicate check, is clearly controlled 

by these parameters. Semantics is clear to users. 

- control of storage space is better (much less chance to overflow available space) 

- synchronization between sender and receiver via protocol (same understanding 

on both sides, of persistence conditions). 

Drawbacks: 

- possible abuse by users (the RMP may have to "cap" these values, based 

on some configuration). 

- implementors must implement these rules in order to conform to spec (more complex). 

Proposal #2: (timeless) 

------------ 

Does NOT specify ExpiryTime, GroupExpiryTime, MaxGroupIdleTime. 

Instead, groups and message IDs are kept open and persisting until some garbage 

collection takes place, controlled by config for each implementation. 

Advantage: 

- no "termination" management is required to conform to specification. Simpler spec, 

Easier to implement. 

Drawbacks: 

- the contract about the scope of dup elimination, of group duration, is unclear 

as controlled by storage availability, possibly differently by each impleemntation. 

- synchronization of termination and removal of states between Sender and Receiver unclear. 

- more chance to overflow available storage, watermark parameters for space limits 

will be reached more often, making terminations of persisted groups and message IDs 

unpredictable.