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Extract from the Register of European Patents

EP About this file: EP3284231

EP3284231 - METHOD AND DEVICE FOR ESTABLISHING A COMPUTATIONAL PUZZLE FOR USE IN COMMUNICATION BETWEEN A CLIENT AND A SERVER. [Right-click to bookmark this link]
StatusNo opposition filed within time limit
Status updated on  03.07.2020
Database last updated on 11.04.2026
FormerThe patent has been granted
Status updated on  07.06.2019
FormerGrant of patent is intended
Status updated on  15.04.2019
FormerExamination is in progress
Status updated on  30.11.2018
FormerRequest for examination was made
Status updated on  19.01.2018
FormerThe international publication has been made
Status updated on  20.09.2017
Most recent event   Tooltip08.07.2022Lapse of the patent in a contracting state
New state(s): MK		published on 10.08.2022  [2022/32]
Applicant(s)For all designated states
Telefonaktiebolaget LM Ericsson (publ)
164 83 Stockholm / SE
[2018/08]
Inventor(s)01 / SELANDER, Göran
Fredrikslundsvägen 28
168 34 Bromma / SE
02 / DUBROVA, Elena
Lillies Väg 80
192 74 Sollentuna / SE
03 / LINDQVIST, Fredrik
Karlavagnsgränd 24
175 66 Järfälla / SE
04 / NÄSLUND, Mats
Stopvägen 95
168 36 Bromma / SE
 [2018/08]
Representative(s)Ericsson
Patent Development
Torshamnsgatan 21-23
164 80 Stockholm / SE
[2018/08]
Application number, filing date15889333.916.04.2015
[2018/08]
WO2015SE50439
Filing languageEN
Procedural languageEN
PublicationType: A1 Application with search report
No.:WO2016167693
Date:20.10.2016
Language:EN
[2016/42]
Type: A1 Application with search report 
No.:EP3284231
Date:21.02.2018
Language:EN
The application published by WIPO in one of the EPO official languages on 20.10.2016 takes the place of the publication of the European patent application.
[2018/08]
Type: B1 Patent specification 
No.:EP3284231
Date:10.07.2019
Language:EN
[2019/28]
Search report(s)International search report - published on:SE20.10.2016
(Supplementary) European search report - dispatched on:EP02.02.2018
ClassificationIPC:H04L29/06
[2018/10]
CPC:
H04L63/1458 (EP,US); H04L63/08 (US); H04L63/12 (US);
H04L9/0643 (US); H04L65/00 (US)
Former IPC [2018/08]H04L29/02
Designated contracting statesAL,   AT,   BE,   BG,   CH,   CY,   CZ,   DE,   DK,   EE,   ES,   FI,   FR,   GB,   GR,   HR,   HU,   IE,   IS,   IT,   LI,   LT,   LU,   LV,   MC,   MK,   MT,   NL,   NO,   PL,   PT,   RO,   RS,   SE,   SI,   SK,   SM,   TR [2018/08]
Extension statesBANot yet paid
MENot yet paid
Validation statesMANot yet paid
TitleGerman:VERFAHREN UND VORRICHTUNG ZUM AUFBAU EINES RECHNERGESTÜTZTEN PUZZLES ZUR VERWENDUNG IN DER KOMMUNIKATION ZWISCHEN EINEM CLIENT UND EINEM SERVER[2018/08]
English:METHOD AND DEVICE FOR ESTABLISHING A COMPUTATIONAL PUZZLE FOR USE IN COMMUNICATION BETWEEN A CLIENT AND A SERVER.[2018/08]
French:PROCÉDÉ ET DISPOSITIF POUR ÉTABLIR UN PUZZLE DE CALCUL À UTILISER DANS UNE COMMUNICATION ENTRE UN CLIENT ET UN SERVEUR.[2018/08]
Entry into regional phase20.09.2017National basic fee paid 
20.09.2017Search fee paid 
20.09.2017Designation fee(s) paid 
20.09.2017Examination fee paid 
Examination procedure20.09.2017Examination requested  [2018/08]
20.09.2017Date on which the examining division has become responsible
20.08.2018Amendment by applicant (claims and/or description)
03.12.2018Despatch of a communication from the examining division (Time limit: M04)
19.03.2019Reply to a communication from the examining division
16.04.2019Communication of intention to grant the patent
28.05.2019Fee for grant paid
28.05.2019Fee for publishing/printing paid
28.05.2019Receipt of the translation of the claim(s)
Opposition(s)03.06.2020No opposition filed within time limit [2020/32]
Fees paidRenewal fee
30.10.2017Renewal fee patent year 03
27.04.2018Renewal fee patent year 04
29.04.2019Renewal fee patent year 05
Opt-out from the exclusive  Tooltip
competence of the Unified
Patent Court		 See the Register of the Unified Patent Court for opt-out data
Responsibility for the accuracy, completeness or quality of the data displayed under the link provided lies entirely with the Unified Patent Court.
Lapses during opposition  TooltipHU16.04.2015
AL10.07.2019
AT10.07.2019
CY10.07.2019
CZ10.07.2019
DK10.07.2019
EE10.07.2019
ES10.07.2019
FI10.07.2019
HR10.07.2019
IT10.07.2019
LT10.07.2019
LV10.07.2019
MC10.07.2019
MK10.07.2019
MT10.07.2019
NL10.07.2019
PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
IE16.04.2020
LU16.04.2020
BE30.04.2020
CH30.04.2020
LI30.04.2020
[2022/32]
Former [2022/28]HU16.04.2015
AL10.07.2019
AT10.07.2019
CY10.07.2019
CZ10.07.2019
DK10.07.2019
EE10.07.2019
ES10.07.2019
FI10.07.2019
HR10.07.2019
IT10.07.2019
LT10.07.2019
LV10.07.2019
MC10.07.2019
MT10.07.2019
NL10.07.2019
PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
IE16.04.2020
LU16.04.2020
BE30.04.2020
CH30.04.2020
LI30.04.2020
Former [2021/20]AL10.07.2019
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RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
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TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
IE16.04.2020
LU16.04.2020
BE30.04.2020
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Former [2021/13]AL10.07.2019
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PL10.07.2019
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RS10.07.2019
SE10.07.2019
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SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
LU16.04.2020
BE30.04.2020
CH30.04.2020
LI30.04.2020
Former [2021/08]AL10.07.2019
AT10.07.2019
CZ10.07.2019
DK10.07.2019
EE10.07.2019
ES10.07.2019
FI10.07.2019
HR10.07.2019
IT10.07.2019
LT10.07.2019
LV10.07.2019
MC10.07.2019
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PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
LU16.04.2020
CH30.04.2020
LI30.04.2020
Former [2020/52]AL10.07.2019
AT10.07.2019
CZ10.07.2019
DK10.07.2019
EE10.07.2019
ES10.07.2019
FI10.07.2019
HR10.07.2019
IT10.07.2019
LT10.07.2019
LV10.07.2019
MC10.07.2019
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PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
IS10.11.2019
PT11.11.2019
Former [2020/37]AL10.07.2019
AT10.07.2019
CZ10.07.2019
DK10.07.2019
EE10.07.2019
ES10.07.2019
FI10.07.2019
HR10.07.2019
IT10.07.2019
LT10.07.2019
LV10.07.2019
NL10.07.2019
PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SI10.07.2019
SK10.07.2019
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TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
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PT11.11.2019
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EE10.07.2019
ES10.07.2019
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IT10.07.2019
LT10.07.2019
LV10.07.2019
NL10.07.2019
PL10.07.2019
RO10.07.2019
RS10.07.2019
SE10.07.2019
SK10.07.2019
SM10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
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DK10.07.2019
EE10.07.2019
ES10.07.2019
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IT10.07.2019
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RS10.07.2019
SE10.07.2019
SK10.07.2019
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TR10.07.2019
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NO10.10.2019
GR11.10.2019
PT11.11.2019
IS24.02.2020
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IT10.07.2019
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SE10.07.2019
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LT10.07.2019
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PL10.07.2019
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TR10.07.2019
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NO10.10.2019
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PT11.11.2019
Former [2020/22]AL10.07.2019
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LV10.07.2019
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RS10.07.2019
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TR10.07.2019
BG10.10.2019
NO10.10.2019
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PT11.11.2019
Former [2020/17]AL10.07.2019
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LT10.07.2019
LV10.07.2019
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RS10.07.2019
SE10.07.2019
TR10.07.2019
BG10.10.2019
NO10.10.2019
GR11.10.2019
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PT11.11.2019
Former [2020/15]AL10.07.2019
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SE10.07.2019
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IS10.11.2019
PT11.11.2019
Former [2020/12]AT10.07.2019
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LV10.07.2019
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SE10.07.2019
BG10.10.2019
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GR11.10.2019
IS10.11.2019
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Former [2020/11]AT10.07.2019
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LV10.07.2019
NL10.07.2019
RS10.07.2019
SE10.07.2019
BG10.10.2019
NO10.10.2019
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PT11.11.2019
Former [2020/10]AT10.07.2019
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NL10.07.2019
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BG10.10.2019
NO10.10.2019
PT11.11.2019
Former [2020/09]FI10.07.2019
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NL10.07.2019
NO10.10.2019
Former [2020/08]LT10.07.2019
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NO10.10.2019
Former [2020/07]NL10.07.2019
Documents cited:Search[X]   ISAAC CHIEN-WEI LEE: "A Novel Design and Implementation of DoS-Resistant Authentication and Seamless Handoff Scheme for Enterprise WLANs", 1 January 2010 (2010-01-01), XP055444481, Retrieved from the Internet [retrieved on 20180125] [X] 1-16 * abstract * * Chapter 5: "DoS Mitigation with Client Puzzles"; pages 57-74 *
 [A]   BRENT WATERS ET AL: "New client puzzle outsourcing techniques for DoS resistance", PROCEEDINGS OF THE 11TH ACM CONFERENCE ON COMPUTER AND COMMUNICATIONS SECURITY : WASHINGTON, DC, USA, OCTOBER 25 - 29, 2004; [ACM CONFERENCE ON COMPUTER AND COMMUNICATIONS SECURITY], NEW YORK, NY : ACM PRESS, 2 PENN PLAZA, SUITE 701 NEW YORK NY 10121, 25 October 2004 (2004-10-25), pages 246 - 256, XP058347824, ISBN: 978-1-58113-961-7, DOI: 10.1145/1030083.1030117 [A] 1-16 * abstract * * Chapter 3: "System Description"; page 250, column r - page 252, column l *

DOI:   http://dx.doi.org/10.1145/1030083.1030117
 [A]   RALPH C MERKLE: "Secure communications over insecure channels", COMMUNICATIONS OF THE ACM, ASSOCIATION FOR COMPUTING MACHINERY, INC, UNITED STATES, vol. 21, no. 4, 1 April 1978 (1978-04-01), pages 294 - 299, XP058136104, ISSN: 0001-0782, DOI: 10.1145/359460.359473 [A] 1-16 * abstract * * "The New Approach"; page 295, column r - page 296, column l * * "The Method"; page 296, column l - page 298, column l *

DOI:   http://dx.doi.org/10.1145/359460.359473
International search[A] US2009217386  (SCHNEIDER JAMES PAUL et al.) [A] 1-48 * ; abstract; paragraphs [0019]-[0024] *
 [A] US7694335  (TURNER BRYAN C et al.) [A] 1-48 * ; abstract; column 2, line 1 - column 3, line 44 *
 [A] US2007157300  (SIVARADJANE PERUMAL R et al.) [A] 1-48 * ; abstract *
 [A] US2003172159  (SCHUBA CHRISTOPH L et al.) [A] 1-48 * ; abstract *
 [A] EP1631037  (NTT DOCOMO INC et al.) [A] 1-48 * ; abstract; paragraphs [0007]-[0011] *
 [A]   ANDREAS GABRIELSSON ET AL.: "Analysis of the Client Puzzles protocol.", BACHELOR'S THESIS AT CSC KTH., 21 May 2012 (2012-05-21), XP055321680 [A] 1-48
 [A]   JOHN BRAINARD: "Client Puzzles: A Cryptographic Countermeasure Against Connection Depletion Attacks", ARIE JUELS, 1999, XP055321684 [A] 1-48
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