aboutsummaryrefslogtreecommitdiff
path: root/src/include/gnunet_ats_service.h
blob: 0ee3d553508494abf40e538de98b709654141f3a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
/*
     This file is part of GNUnet.
     (C) 2010,2011 Christian Grothoff (and other contributing authors)

     GNUnet is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published
     by the Free Software Foundation; either version 3, or (at your
     option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/
/**
 * @file include/gnunet_ats_service.h
 * @brief automatic transport selection and outbound bandwidth determination
 * @author Christian Grothoff
 * @author Matthias Wachs
 */
#ifndef GNUNET_ATS_SERVICE_H
#define GNUNET_ATS_SERVICE_H

#include "gnunet_constants.h"
#include "gnunet_util_lib.h"
#include "gnunet_hello_lib.h"


enum GNUNET_ATS_Network_Type
{
  GNUNET_ATS_NET_UNSPECIFIED = 0,
  GNUNET_ATS_NET_LOOPBACK = 1,
  GNUNET_ATS_NET_LAN = 2,
  GNUNET_ATS_NET_WAN = 3,
  GNUNET_ATS_NET_WLAN = 4,
};

/**
 * Enum defining all known property types for ATS Enum values are used
 * in the GNUNET_ATS_Information struct as
 * (key,value)-pairs.
 *
 * Cost are always stored in uint32_t, so all units used to define costs
 * have to be normalized to fit in uint32_t [0 .. 4.294.967.295]
 */
enum GNUNET_ATS_Property
{

  /**
   * End of the array.
   * @deprecated
   */
  GNUNET_ATS_ARRAY_TERMINATOR = 0,

  /**
   * Actual traffic on this connection from the other peer to this peer.
   *
   * Unit: [bytes/second]
   */
  GNUNET_ATS_UTILIZATION_UP,

  /**
   * Actual traffic on this connection from this peer to the other peer.
   *
   * Unit: [bytes/second]
   */
  GNUNET_ATS_UTILIZATION_DOWN,

  /**
   * Is this address located in WAN, LAN or a loopback address
   * Value is element of GNUNET_ATS_Network_Type
   */
  GNUNET_ATS_NETWORK_TYPE,

  /**
   * Delay
   * Time between when the time packet is sent and the packet arrives
   *
   * Unit: [ms]
   *
   * Examples:
   *
   * LAN   :    1
   * WLAN  :    2
   * Dialup:  500
   */
  GNUNET_ATS_QUALITY_NET_DELAY,

  /**
   * Distance on network layer (required for distance-vector routing).
   *
   * Unit: [DV-hops]
   */
  GNUNET_ATS_QUALITY_NET_DISTANCE,

  /**
   * Network overhead on WAN (Wide-Area Network)
   *
   * How many bytes are sent on the WAN when 1 kilobyte (1024 bytes)
   * of application data is transmitted?
   * A factor used with connect cost, bandwidth cost and energy cost
   * to describe the overhead produced by the transport protocol
   *
   * Unit: [bytes/kb]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * TCP/IPv4 over Ethernet: 1024 + 38 + 20 + 20 = 1102 [bytes/kb]
   * TCP/IPv6 over Ethernet: 1024 + 38 + 20 + 40 = 1122 [bytes/kb]
   * UDP/IPv4 over Ethernet: 1024 + 38 + 20 + 8  = 1090 [bytes/kb]
   * UDP/IPv6 over Ethernet: 1024 + 38 + 40 + 8  = 1110 [bytes/kb]
   */
  GNUNET_ATS_COST_WAN,

  /**
   * Network overhead on LAN (Local-Area Network)
   *
   * How many bytes are sent on the LAN when 1 kilobyte (1024 bytes)
   * of application data is transmitted?
   * A factor used with connect cost, bandwidth cost and energy cost
   * to describe the overhead produced by the transport protocol
   *
   * Unit: [bytes/kb]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * TCP/IPv4 over Ethernet: 1024 + 38 + 20 + 20 = 1102 [bytes/kb]
   * TCP/IPv6 over Ethernet: 1024 + 38 + 20 + 40 = 1122 [bytes/kb]
   * UDP/IPv4 over Ethernet: 1024 + 38 + 20 + 8  = 1090 [bytes/kb]
   * UDP/IPv6 over Ethernet: 1024 + 38 + 40 + 8  = 1110 [bytes/kb]
   */
  GNUNET_ATS_COST_LAN,

  /**
   * Network overhead on WLAN (Wireless Local Area Network)
   *
   * How many bytes are sent on the LAN when 1 kilobyte (1024 bytes)
   * of application data is transmitted?
   * A factor used with connect cost, bandwidth cost and energy cost
   * to describe the overhead produced by the transport protocol
   *
   * Unit: [bytes/kb]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * TCP/IPv4 over Ethernet: 1024 + 38 + 20 + 20 = 1102 [bytes/kb]
   * TCP/IPv6 over Ethernet: 1024 + 38 + 20 + 40 = 1122 [bytes/kb]
   * UDP/IPv4 over Ethernet: 1024 + 38 + 20 + 8  = 1090 [bytes/kb]
   * UDP/IPv6 over Ethernet: 1024 + 38 + 40 + 8  = 1110 [bytes/kb]
   */
  GNUNET_ATS_COST_WLAN
      /* Cost related values */
      /* =================== */
  /**
   * Volume based cost in financial units to transmit data
   *
   * Note: This value is not bound to a specific currency or unit and only
   * used locally.
   * "cent" just refers the smallest amount of money in the respective
   * currency.
   *
   * Unit: [cent/MB]
   *
   * Interpretation: less is better
   *
   * Examples:
   * LAN:  0 [cent/MB]
   * 2G : 10 [cent/MB]
   */
      // GNUNET_ATS_COST_FINANCIAL_PER_VOLUME = 1,
  /**
   * Time based cost in financial units to transmit data
   *
   * Note: This value is not bound to a specific currency or unit and only
   * used locally.
   * "cent" just refers the smallest amount of money in the respective
   * currency.
   *
   * Unit: [cent/h]
   *
   * Interpretation: less is better
   *
   * Examples:
   * LAN   :  0 [cent/h]
   * Dialup: 10 [cent/h]
   */
      // GNUNET_ATS_COST_FINANCIAL_PER_TIME = 2,
  /**
   * Computational costs
   *
   * Effort of preparing data to be sent with this transport
   * Includes encoding, encryption and conversion of data
   * Partial values can be summed up: c_sum = c_enc + c_enc + c_conv
   * Resulting values depend on local system properties, e.g. CPU
   *
   * Unit: [ms/GB]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * HTTPS with AES CBC-256: 	7,382
   * HTTPS with AES CBC-128: 	5,279
   * HTTPS with RC4-1024: 	2,652
   */
      // GNUNET_ATS_COST_COMPUTATIONAL = 3,
  /**
   * Energy consumption
   *
   * Energy consumption using this transport when sending with a certain
   * power at a certain bitrate. This is only an approximation based on:
   * Energy consumption E = P / D
   *
   * with:
   * Power P in Watt (J/s)
   * Datarate D in MBit/s
   *
   * Conversion between power P and dBm used by WLAN in radiotap's dBm TX power:
   *
   * Lp(dbm) = 10 log10 (P/ 1mW)
   *
   * => P = 1 mW  * 10^(Lp(dbm)/10)
   *
   * Unit: [mJ/MB]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * LAN:       0
   * WLAN:      89 (600 mW @ 802.11g /w 54 MBit/s)
   * Bluetooth: 267 (100 mW @ BT2.0 EDR /w 3 MBit/s)
   */
      // GNUNET_ATS_COST_ENERGY_CONSUMPTION = 4,
  /**
   * Connect cost
   * How many bytes are transmitted to initiate a new connection using
   * this transport?
   *
   * Unit: [bytes]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * UDP (No connection)      :
   *     0 bytes
   * TCP (TCP 3-Way handshake):
   *   220 bytes Ethernet,  172 bytes TCP/IP,  122 bytes TCP
   * HTTP (TCP + Header)      :
   *   477 bytes Ethernet,  429 bytes TCP/IP,  374 bytes TCP,  278 bytes HTTP
   * HTTPS  HTTP+TLS Handshake:
   *  2129 bytes Ethernet, 1975 bytes TCP/IP, 1755 bytes TCP, 1403 bytes HTTPS
   *
   * */
      // GNUNET_ATS_COST_CONNECT = 5,
  /**
   * Bandwidth cost
   *
   * How many bandwidth is available to consume?
   * Used to calculate which impact sending data with this transport has
   *
   * Unit: [kB/s]
   *
   * Interpretation: more is better
   *
   * Examples:
   * LAN:     12,800  (100 MBit/s)
   * WLAN:    6,912   (54 MBit/s)
   * Dial-up: 8       (64 Kbit/s)
   *
   */
      // GNUNET_ATS_COST_BANDWITH_AVAILABLE = 6,
  /**
   *  Network overhead
   *
   * How many bytes are sent over the wire when 1 kilobyte (1024 bytes)
   * of application data is transmitted?
   * A factor used with connect cost, bandwidth cost and energy cost
   * to describe the overhead produced by the transport protocol
   *
   * Unit: [bytes/kb]
   *
   * Interpretation: less is better
   *
   * Examples:
   *
   * TCP/IPv4 over Ethernet: 1024 + 38 + 20 + 20 = 1102 [bytes/kb]
   * TCP/IPv6 over Ethernet: 1024 + 38 + 20 + 40 = 1122 [bytes/kb]
   * UDP/IPv4 over Ethernet: 1024 + 38 + 20 + 8  = 1090 [bytes/kb]
   * UDP/IPv6 over Ethernet: 1024 + 38 + 40 + 8  = 1110 [bytes/kb]
   */
      // GNUNET_ATS_COST_NETWORK_OVERHEAD = 7,
      /* Quality related values */
      /* ====================== */
      /* Physical layer quality properties */
  /**
   * Signal strength on physical layer
   *
   * Unit: [dBm]
   */
      // GNUNET_ATS_QUALITY_PHY_SIGNAL_STRENGTH = 1025,
  /**
   * Collision rate on physical layer
   *
   * Unit: [B/s]
   */
      // GNUNET_ATS_QUALITY_PHY_COLLISION_RATE = 1026,
  /**
   * Error rate on physical layer
   *
   * Unit: [B/s]
   */
      // GNUNET_ATS_QUALITY_PHY_ERROR_RATE = 1027,
  /**
   * Jitter
   * Time variations of the delay
   * 1st derivative of a delay function
   *
   * Unit: [ms]
   */
      // GNUNET_ATS_QUALITY_NET_JITTER = 1029,
  /**
   * Error rate on network layer
   *
   * Unit: [B/s]
   *
   * Examples:
   *
   * LAN       :    0
   * WLAN      :  400
   * Bluetooth :  100
   * Note: This numbers are just assumptions as an example, not
   * measured or somehow determined
   */
      // GNUNET_ATS_QUALITY_NET_ERRORRATE = 1030,
  /**
   * Drop rate on network layer
   * Bytes actively dismissed by a network component during transmission
   * Reasons for dropped data can be full queues, congestion, quota violations...
   *
   * Unit: [B/s]
   *
   * Examples:
   *
   * LAN       :    0
   * WLAN      :  400
   * Bluetooth :  100
   * Note: This numbers are just assumptions as an example, not
   * measured or somehow determined
   */
      // GNUNET_ATS_QUALITY_NET_DROPRATE = 1031,
  /**
   * Loss rate on network layer
   * Bytes lost during transmission
   * Reasons can be collisions, ...
   *
   * Unit: [B/s]
   *
   * Examples:
   *
   * LAN       :    0
   * WLAN      :   40
   * Bluetooth :   10
   * Note: This numbers are just assumptions as an example, not measured
   * or somehow determined
   */
      // GNUNET_ATS_QUALITY_NET_LOSSRATE = 1032,
  /**
   * Throughput on network layer
   *
   * Unit: [kB/s]
   *
   * Examples:
   *
   * LAN   : 3400
   * WLAN  : 1200
   * Dialup: 	  4
   *
   */
      // GNUNET_ATS_QUALITY_NET_THROUGHPUT = 1033,
      /* Availability related values */
      /* =========================== */
  /**
   * Is a peer reachable?
   */
      // GNUNET_ATS_AVAILABILITY_REACHABLE = 2048,
  /**
   * Is there a connection established to a peer using this transport
   */
      // GNUNET_ATS_AVAILABILITY_CONNECTED = 2049
};

/**
 * Number of ATS quality properties
 */
#define GNUNET_ATS_QualityPropertiesCount 2

/**
 * ATS quality properties as array initializer
 */
#define GNUNET_ATS_QualityProperties {GNUNET_ATS_QUALITY_NET_DELAY, GNUNET_ATS_QUALITY_NET_DISTANCE}

/**
 * Number of ATS quality properties
 */
#define GNUNET_ATS_NetworkTypeCount 5

/**
 * ATS quality properties as array initializer
 */
#define GNUNET_ATS_NetworkType {GNUNET_ATS_NET_UNSPECIFIED, GNUNET_ATS_NET_LOOPBACK, GNUNET_ATS_NET_LAN, GNUNET_ATS_NET_WAN, GNUNET_ATS_NET_WLAN}

GNUNET_NETWORK_STRUCT_BEGIN

/**
 * struct used to communicate the transport's properties like cost and
 * quality of service as well as high-level constraints on resource
 * consumption.
 *
 *                             +---+
 *  +-----------+ Constraints  |   |  Plugin properties +---------+
 *  | Highlevel |------------> |ATS| <------------------|Transport|
 *  | Component | ATS struct   |   |    ATS struct      | Plugin  |
 *  +-----------+              |   |                    +---------+
 *                             +---+
 *
 * This structure will be used by transport plugins to communicate
 * costs to ATS or by higher level components to tell ATS their
 * constraints.  Always a pair of (GNUNET_ATS_Property,
 * uint32_t value).  Value is always uint32_t, so all units used to
 * define costs have to be normalized to fit uint32_t.
 */
struct GNUNET_ATS_Information
{
  /**
   * ATS property type, in network byte order.
   */
  uint32_t type GNUNET_PACKED;

  /**
   * ATS property value, in network byte order.
   */
  uint32_t value GNUNET_PACKED;
};
GNUNET_NETWORK_STRUCT_END


/* ******************************** Scheduling API ***************************** */

/**
 * Handle to the ATS subsystem for bandwidth/transport scheduling information.
 */
struct GNUNET_ATS_SchedulingHandle;


/**
 * Opaque session handle, defined by plugins.  Contents not known to ATS.
 */
struct Session;


/**
 * Signature of a function called by ATS with the current bandwidth
 * and address preferences as determined by ATS.
 *
 * @param cls closure
 * @param address suggested address (including peer identity of the peer)
 * @param session session to use
 * @param bandwidth_out assigned outbound bandwidth for the connection
 * @param bandwidth_in assigned inbound bandwidth for the connection
 * @param ats performance data for the address (as far as known)
 * @param ats_count number of performance records in 'ats'
 */
typedef void (*GNUNET_ATS_AddressSuggestionCallback) (void *cls,
                                                      const struct
                                                      GNUNET_HELLO_Address *
                                                      address,
                                                      struct Session * session,
                                                      struct
                                                      GNUNET_BANDWIDTH_Value32NBO
                                                      bandwidth_out,
                                                      struct
                                                      GNUNET_BANDWIDTH_Value32NBO
                                                      bandwidth_in,
                                                      const struct
                                                      GNUNET_ATS_Information *
                                                      ats, uint32_t ats_count);


/**
 * Initialize the ATS subsystem.
 *
 * @param cfg configuration to use
 * @param suggest_cb notification to call whenever the suggestation changed
 * @param suggest_cb_cls closure for 'suggest_cb'
 * @return ats context
 */
struct GNUNET_ATS_SchedulingHandle *
GNUNET_ATS_scheduling_init (const struct GNUNET_CONFIGURATION_Handle *cfg,
                            GNUNET_ATS_AddressSuggestionCallback suggest_cb,
                            void *suggest_cb_cls);


/**
 * Client is done with ATS scheduling, release resources.
 *
 * @param sh handle to release
 */
void
GNUNET_ATS_scheduling_done (struct GNUNET_ATS_SchedulingHandle *sh);


/**
 * We would like to establish a new connection with a peer.  ATS
 * should suggest a good address to begin with.
 *
 * @param sh handle
 * @param peer identity of the peer we need an address for
 */
void
GNUNET_ATS_suggest_address (struct GNUNET_ATS_SchedulingHandle *sh,
                            const struct GNUNET_PeerIdentity *peer);


/**
 * We want to cancel ATS suggesting addresses for a peer.
 *
 * @param sh handle
 * @param peer identity of the peer
 */
void
GNUNET_ATS_suggest_address_cancel (struct GNUNET_ATS_SchedulingHandle *sh,
                                   const struct GNUNET_PeerIdentity *peer);


/**
 * Returns where the address is located: LAN or WAN or ...
 * @param sh the GNUNET_ATS_SchedulingHandle handle
 * @param addr address
 * @param addrlen address length
 * @return location as GNUNET_ATS_Information
 */
struct GNUNET_ATS_Information
GNUNET_ATS_address_get_type (struct GNUNET_ATS_SchedulingHandle *sh,
                             const struct sockaddr * addr,
                             socklen_t addrlen);


/**
 * We have updated performance statistics for a given address.  Note
 * that this function can be called for addresses that are currently
 * in use as well as addresses that are valid but not actively in use.
 * Furthermore, the peer may not even be connected to us right now (in
 * which case the call may be ignored or the information may be stored
 * for later use).  Update bandwidth assignments.
 *
 * @param sh handle
 * @param address updated address
 * @param session session handle (if available)
 * @param ats performance data for the address
 * @param ats_count number of performance records in 'ats'
 */
void
GNUNET_ATS_address_update (struct GNUNET_ATS_SchedulingHandle *sh,
                           const struct GNUNET_HELLO_Address *address,
                           struct Session *session,
                           const struct GNUNET_ATS_Information *ats,
                           uint32_t ats_count);


/**
 * An address is now in use or not used any more.
 *
 * @param sh handle
 * @param address the address
 * @param session session handle
 * @param in_use GNUNET_YES if this address is now used, GNUNET_NO
 * if address is not used any more
 */
void
GNUNET_ATS_address_in_use (struct GNUNET_ATS_SchedulingHandle *sh,
                           const struct GNUNET_HELLO_Address *address,
                           struct Session *session, int in_use);

/**
 * A session got destroyed, stop including it as a valid address.
 *
 * @param sh handle
 * @param address the address
 * @param session session handle that is no longer valid (if available)
 */
void
GNUNET_ATS_address_destroyed (struct GNUNET_ATS_SchedulingHandle *sh,
                              const struct GNUNET_HELLO_Address *address,
                              struct Session *session);


/* ******************************** Performance API ***************************** */

/**
 * ATS Handle to obtain and/or modify performance information.
 */
struct GNUNET_ATS_PerformanceHandle;


/**
 * Signature of a function that is called with QoS information about a peer.
 *
 * @param cls closure
 * @param address the address
 * @param bandwidth_out assigned outbound bandwidth for the connection
 * @param bandwidth_in assigned inbound bandwidth for the connection
 * @param ats performance data for the address (as far as known)
 * @param ats_count number of performance records in 'ats'
 */
typedef void (*GNUNET_ATS_PeerInformationCallback) (void *cls,
                                                    const struct
                                                    GNUNET_HELLO_Address *
                                                    address,
                                                    struct
                                                    GNUNET_BANDWIDTH_Value32NBO
                                                    bandwidth_out,
                                                    struct
                                                    GNUNET_BANDWIDTH_Value32NBO
                                                    bandwidth_in,
                                                    const struct
                                                    GNUNET_ATS_Information *
                                                    ats, uint32_t ats_count);


/**
 * Get handle to access performance API of the ATS subsystem.
 *
 * @param cfg configuration to use
 * @param infocb function to call on performance changes, can be NULL
 * @param infocb_cls closure for infocb
 * @return ats performance context
 */
struct GNUNET_ATS_PerformanceHandle *
GNUNET_ATS_performance_init (const struct GNUNET_CONFIGURATION_Handle *cfg,
                             GNUNET_ATS_PeerInformationCallback infocb,
                             void *infocb_cls);


/**
 * Client is done using the ATS performance subsystem, release resources.
 *
 * @param ph handle
 */
void
GNUNET_ATS_performance_done (struct GNUNET_ATS_PerformanceHandle *ph);


/**
 * Function called with reservation result.
 *
 * @param cls closure
 * @param peer identifies the peer
 * @param amount set to the amount that was actually reserved or unreserved;
 *               either the full requested amount or zero (no partial reservations)
 * @param res_delay if the reservation could not be satisfied (amount was 0), how
 *        long should the client wait until re-trying?
 */
typedef void (*GNUNET_ATS_ReservationCallback) (void *cls,
                                                const struct GNUNET_PeerIdentity
                                                * peer, int32_t amount,
                                                struct GNUNET_TIME_Relative
                                                res_delay);



/**
 * Context that can be used to cancel a peer information request.
 */
struct GNUNET_ATS_ReservationContext;


/**
 * Reserve inbound bandwidth from the given peer.  ATS will look at
 * the current amount of traffic we receive from the peer and ensure
 * that the peer could add 'amount' of data to its stream.
 *
 * @param ph performance handle
 * @param peer identifies the peer
 * @param amount reserve N bytes for receiving, negative
 *                amounts can be used to undo a (recent) reservation;
 * @param rcb function to call with the resulting reservation information
 * @param rcb_cls closure for info
 * @return NULL on error
 * @deprecated will be replaced soon
 */
struct GNUNET_ATS_ReservationContext *
GNUNET_ATS_reserve_bandwidth (struct GNUNET_ATS_PerformanceHandle *ph,
                              const struct GNUNET_PeerIdentity *peer,
                              int32_t amount,
                              GNUNET_ATS_ReservationCallback rcb,
                              void *rcb_cls);


/**
 * Cancel request for reserving bandwidth.
 *
 * @param rc context returned by the original GNUNET_ATS_reserve_bandwidth call
 */
void
GNUNET_ATS_reserve_bandwidth_cancel (struct GNUNET_ATS_ReservationContext *rc);



/**
 * Enum defining all known preference categories.
 */
enum GNUNET_ATS_PreferenceKind
{

  /**
   * End of preference list.
   */
  GNUNET_ATS_PREFERENCE_END = 0,

  /**
   * Change the peer's bandwidth value (value per byte of bandwidth in
   * the goal function) to the given amount.  The argument is followed
   * by a double value giving the desired value (can be negative).
   * Preference changes are forgotten if peers disconnect.
   */
  GNUNET_ATS_PREFERENCE_BANDWIDTH,

  /**
   * Change the peer's latency value to the given amount.  The
   * argument is followed by a double value giving the desired value
   * (can be negative).  The absolute score in the goal function is
   * the inverse of the latency in ms (minimum: 1 ms) multiplied by
   * the latency preferences.
   */
  GNUNET_ATS_PREFERENCE_LATENCY
};


/**
 * Change preferences for the given peer. Preference changes are forgotten if peers
 * disconnect.
 *
 * @param ph performance handle
 * @param peer identifies the peer
 * @param ... 0-terminated specification of the desired changes
 */
void
GNUNET_ATS_change_preference (struct GNUNET_ATS_PerformanceHandle *ph,
                              const struct GNUNET_PeerIdentity *peer, ...);



#endif
/* end of file gnunet-service-transport_ats.h */