[Sis-ams] 'reconnect' timer?

[Scott Burleigh]

Ray, Timothy J. (GSFC-583.0) wrote:
>
> Scott,
>
>  
>
> Ok.  I think I understand your idea.  What follows is an attempt to 
> describe it in my own words (boy, it's much easier to implement 
> something than to specify it!).
>
>  
>
> With regard to the heartbeat cycle, a node can be thought of as having 
> 3 states:
>
>     * Registered -- For each heartbeat-cycle, the node sends a
>       heartbeat and checks to see if a heartbeat was received.  If the
>       incoming heartbeat is missed for N6 consecutive
>       heartbeat-cycles, then the registrar's death is imputed and the
>       state changes to 'reconnecting'.
>     * Reconnecting -- For each heartbeat-cycle, the node initiates a
>       sequence of message exchanges (AMS devotees know the details
>       here -- for example, send a 'registrar-query' to the server,
>       receive a 'cell-spec' from the server, send a 'reconnect' to the
>       restarted registrar, ...) with outcomes that fall into 3
>       categories.   First, if "fully successful", the node will
>       receive a 'reconnected' response from the restarted registrar
>       (and change state to 'registered').  Second, if "fully
>       unsuccessful", the node will receive a 'you-are-dead' response
>       from the registrar, and change state to 'unregistered'.  Third,
>       all other possible outcomes result in no change -- i.e the
>       'reconnect' sequence will be initiated again during the
>       following hearbeat cycle.
>     * Unregistered -- This state applies whenever the node is neither
>       'registered' nor 'reconnecting'.  We can either say that there
>       is no heartbeat-cycle while in this state, or that there is a
>       heartbeat cycle but no action is taken.
>
>  
>
> How does this line up with your thinking?
>
I think this is a good way of putting it, Tim.  I should think about it 
a little more to convince myself that it covers all the edge cases, but 
on first reading it looks right.

Scott
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