ostore.agree
Class RingState

java.lang.Object
  |
  +--ostore.agree.RingState

public class RingState

extends Object

The state associated with a given ring (public key). Logically, this class is a subclass of ThresholdByzantine. It's in a separate file only to make the programming easier. (I often edit the two simultaneously.)

Version:

$Id: RingState.java,v 1.9 2002/12/07 03:18:04 srhea Exp $

Author:

Sean C. Rhea

Field Summary

SortedMap	agreement_states Maps sequence numbers (Longs) to their AgreementStates.
Set	already_seen_digests
long	current_view The current view.
Map	digest_to_seq Maps the digests (SecureHashes) of ongoing requests to their sequence numbers (Longs) in the current view.
Map	guid_to_member Maps the guids of the machines in this ring (SecureHashes) to their member numbers (Integers).
long	highest_active_seq The largest sequence number of all of the agreements seen so far in this view.
KeyShare	key_share Our share of the private key used to create signatures.
long	last_dispatched_req The sequence number of the last request that was sent to the inner ring to be executed.
long	lowest_active_seq The sequence number of the agreement with the lowest sequence number which is still not in the CERTIFIED_STATE.
int	max_fail The maximum number of failures that can occur under the Byzantine assumption.
int	member_count The number of members in this ring.
int	member_num My own member number in this ring.
SecureHash[]	members_guids Maps member numbers to their machine guids.
QSPublicKey[]	members_pkeys The public keys of each of the members in the ring.
LinkedList	pending_agreements Agreements that we have not yet started due to the number of active requests being equal to the window size.
SecureHash	ring_id The hash of the public key used to verify signatures from this ring.
QSPublicKey	ring_pkey The public key used to verify signatures from this ring.
int	window_size The number of active agreements we allow to be in some state other than CERTIFIED_STATE.

Constructor Summary

RingState(SecureHash ring_id, long initial_view, long initial_seq, QSPublicKey ring_public_key, QSPublicKey[] member_public_keys, KeyShare private_key_share, QSPublicKey this_machine_pkey, int window_size)
Construct a new RingState.

Method Summary

long	active_seqs() The number of agreements which have been initiated but not yet reached the CERTIFIED_STATE.
AgreementState	alloc_agreement_state(long seq) Allocate a new AgreementState object.
void	free_agreement_state(AgreementState as) Deallocate an AgreementState object.
int	general_num() The member number of the general in this view.
boolean	general() Are we the general in this view?
boolean	in_window(long seq) Is the given sequence number allowable, given the currently active agreements?
long	window_top() The highest allowable sequence number, given the currently active agreements.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ring_id

public SecureHash ring_id

The hash of the public key used to verify signatures from this ring.

guid_to_member

public Map guid_to_member

Maps the guids of the machines in this ring (SecureHashes) to their member numbers (Integers).

member_count

public int member_count

The number of members in this ring.

member_num

public int member_num

My own member number in this ring.

max_fail

public int max_fail

The maximum number of failures that can occur under the Byzantine assumption.

current_view

public long current_view

The current view.

window_size

public int window_size

The number of active agreements we allow to be in some state other than CERTIFIED_STATE.

members_guids

public SecureHash[] members_guids

Maps member numbers to their machine guids.

ring_pkey

public QSPublicKey ring_pkey

The public key used to verify signatures from this ring.

members_pkeys

public QSPublicKey[] members_pkeys

The public keys of each of the members in the ring.

key_share

public KeyShare key_share

Our share of the private key used to create signatures.

digest_to_seq

public Map digest_to_seq

Maps the digests (SecureHashes) of ongoing requests to their sequence numbers (Longs) in the current view.

already_seen_digests

public Set already_seen_digests

highest_active_seq

public long highest_active_seq

The largest sequence number of all of the agreements seen so far in this view.

lowest_active_seq

public long lowest_active_seq

The sequence number of the agreement with the lowest sequence number which is still not in the CERTIFIED_STATE.

last_dispatched_req

public long last_dispatched_req

The sequence number of the last request that was sent to the inner ring to be executed.

agreement_states

public SortedMap agreement_states

Maps sequence numbers (Longs) to their AgreementStates.

pending_agreements

public LinkedList pending_agreements

Agreements that we have not yet started due to the number of active requests being equal to the window size.

Constructor Detail

RingState

public RingState(SecureHash ring_id,
                 long initial_view,
                 long initial_seq,
                 QSPublicKey ring_public_key,
                 QSPublicKey[] member_public_keys,
                 KeyShare private_key_share,
                 QSPublicKey this_machine_pkey,
                 int window_size)

Construct a new RingState.

Method Detail

general

public final boolean general()

Are we the general in this view?

general_num

public final int general_num()

The member number of the general in this view.

active_seqs

public final long active_seqs()

The number of agreements which have been initiated but not yet reached the CERTIFIED_STATE.

window_top

public final long window_top()

The highest allowable sequence number, given the currently active agreements.

in_window

public final boolean in_window(long seq)

Is the given sequence number allowable, given the currently active agreements?

alloc_agreement_state

public AgreementState alloc_agreement_state(long seq)

Allocate a new AgreementState object. Since there are never any more of these than the window size, and since they're rather large, we keep a list of the one's we've already allocated. Otherwise, every request would require garbage collecting another one. The above is no longer true, as it was the spawning ground for a hord of bugs. We now just use new and the gc, as God intended. --srhea 12/02/2002

free_agreement_state

public void free_agreement_state(AgreementState as)

Deallocate an AgreementState object. See the comments in alloc_agreement_state.