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Cryptanalysis of Microsoft's PPTP Authentication Extensions (MS-CHAPv2) [chapter]

Bruce Schneier, Mudge, David Wagner
1999 Lecture Notes in Computer Science  
We present an overview of the changes in the authentication and encryption-key generation portions of MS-CHAPv2, and assess the improvements and remaining weaknesses in Microsoft's PPTP implementation.  ...  In response to [SM98], Microsoft released extensions to the PPTP authentication mechanism (MS-CHAP), called MS-CHAPv2.  ...  Once the NT hash is recovered, all encrypted sessions can be read and the authentication scheme can be cracked with no effort.  ... 
doi:10.1007/3-540-46701-7_17 fatcat:rsi32a6nwfbvxdioyv2jznpkhm

Cuckoo hashing

Rasmus Pagh, Flemming Friche Rodler
2004 Journal of Algorithms  
variant of open addressing where keys can be moved back in their probe sequences.  ...  Besides being conceptually much simpler than previous dynamic dictionaries with worst case constant lookup time, our data structure is interesting in that it does not use perfect hashing, but rather a  ...  in general.  ... 
doi:10.1016/j.jalgor.2003.12.002 fatcat:3yksbb2ffzgl7jgbnvwdkox7gq

Strongly History-Independent Hashing with Applications

Guy E. Blelloch, Daniel Golovin
2007 Foundations of Computer Science (FOCS), IEEE Annual Symposium on  
The results can be used to construct many other SHI data structures.  ...  It supports comparisons in O(1) worst-case time, and updates in O(1) expected time. All structures use O(n) data space.  ...  Then sample a 5universal hash function h : U → [p] that can be evaluated in constant time.  ... 
doi:10.1109/focs.2007.4389499 fatcat:vf5efgaofraibci66qmq2lhrs4

Strongly History-Independent Hashing with Applications

Guy E. Blelloch, Daniel Golovin
2007 48th Annual IEEE Symposium on Foundations of Computer Science (FOCS'07)  
The results can be used to construct many other SHI data structures.  ...  It supports comparisons in O(1) worst-case time, and updates in O(1) expected time. All structures use O(n) data space.  ...  Then sample a 5universal hash function h : U → [p] that can be evaluated in constant time.  ... 
doi:10.1109/focs.2007.36 dblp:conf/focs/BlellochG07 fatcat:y2x7gzi7nre5doxjqhpk7sq5ba

Cuckoo Filter: Simplification and Analysis [article]

David Eppstein
2016 arXiv   pre-print
We describe a simplified version of the cuckoo filter using fewer hash function calls per query.  ...  The cuckoo filter data structure of Fan, Andersen, Kaminsky, and Mitzenmacher (CoNEXT 2014) performs the same approximate set operations as a Bloom filter in less memory, with better locality of reference  ...  not in the set is falsely reported to be in the set) can easily be bounded by ≤ 2b/(2 f − 1).  ... 
arXiv:1604.06067v1 fatcat:wto74dqsevbjbowj4rc7xlra3y

Cuckoo Filter: Simplification and Analysis

David Eppstein, Marc Herbstritt
2016 Scandinavian Workshop on Algorithm Theory  
We describe a simplified version of the cuckoo filter using fewer hash function calls per query.  ...  The cuckoo filter data structure of Fan, Andersen, Kaminsky, and Mitzenmacher (CoNEXT 2014) performs the same approximate set operations as a Bloom filter in less memory, with better locality of reference  ...  Then each query in the filter may be performed in time O(B).  ... 
doi:10.4230/lipics.swat.2016.8 dblp:conf/swat/Eppstein16 fatcat:ba5vszkmj5gvvmruweumoxhtyq

SipHash: A Fast Short-Input PRF [chapter]

Jean-Philippe Aumasson, Daniel J. Bernstein
2012 Lecture Notes in Computer Science  
For example, SipHash processes a 16-byte input with a fresh key in 140 cycles on an AMD FX-8150 processor, which is much faster than state-of-the-art MACs.  ...  We propose that hash tables switch to SipHash as a hash function.  ...  One can blame the hash-table implementation for leaking information through timing; but it is not easy to build an efficient constant-time hash table.  ... 
doi:10.1007/978-3-642-34931-7_28 fatcat:7m47ds3szbaqde6xhsjlu3vehu

DHV: A Code Consistency Maintenance Protocol for Multi-hop Wireless Sensor Networks [chapter]

Thanh Dang, Nirupama Bulusu, Wu-chi Feng, Seungweon Park
2009 Lecture Notes in Computer Science  
When nodes have different code versions, the network may not behave as intended, wasting time and energy.  ...  DHV can detect and identify version differences in O(1) messages and latency compared to the logarithmic scale of current protocols.  ...  Acknowledgments -This research was supported in part by National Science Foundation grants 0514818 and 0722063.  ... 
doi:10.1007/978-3-642-00224-3_21 fatcat:67fwhh2hmnalbllx37zhfc4abi

Phase-concurrent hash tables for determinism

Julian Shun, Guy E. Blelloch
2014 Proceedings of the 26th ACM symposium on Parallelism in algorithms and architectures - SPAA '14  
times faster on random integer keys when operations are restricted to be phase-concurrent.  ...  We present a deterministic phase-concurrent hash table in which operations of the same type are allowed to proceed concurrently, but operations of different types are not.  ...  This means that searching for keys not in the table can actually be faster than in standard linear probing.  ... 
doi:10.1145/2612669.2612687 dblp:conf/spaa/ShunB14 fatcat:ywjhokjs6zd3rllzk5uiive6b4

Simple Fast Parallel Hashing by Oblivious Execution

Joseph Gil, Yossi Matias
1998 SIAM journal on computing (Print)  
Time efficiency. For every x ∈ U , H(x) can be evaluated in O(1) time by a single processor. Such a function induces a linear space data structure, a perfect hash table, for representing S.  ...  A hash table is a representation of a set in a linear size data structure that supports constant-time membership queries.  ...  All keys that were not hashed in the iterative process will be hashed into an auxiliary hash table of size O(n).  ... 
doi:10.1137/s0097539794291580 fatcat:ncifz4y6szgzvbge2lnq5yudeu

Detecting a Corrupted Area in a 2-Dimensional Space [article]

YounSun Cho
2014 arXiv   pre-print
Motivated by the fact that 2-dimensional data have become popularly used in many applications without being much considered its integrity checking.  ...  We introduce the problem of detecting a corrupted area in a 2-dimensional space, and investigate two possible efficient approaches and show their time and space complexities.  ...  We will provide a full extended version of this paper in a very near future.  ... 
arXiv:1404.1577v1 fatcat:xmacuhaxtbejzpr2z2kmlaomlu

On the Security of NMAC and Its Variants

Fanbao Liu, Changxiang Shen, Tao Xie, Dengguo Feng
2013 TELKOMNIKA (Telecommunication Computing Electronics and Control)  
We propose some key recovery attacks to these NMAC variants, for example, we can recover the equivalent inner key of NMAC in about O(2 n/2 ) MAC operations, in a related key setting.  ...  in HMAC.  ...  As pointed out by the editors of Cryptology ePrint Archive in our preliminary version of this paper, the equivalent key recovery attack to NMAC is not applicable to the practical HMAC, since the HMAC keys  ... 
doi:10.12928/telkomnika.v11i2.940 fatcat:xffovuhpxfdqtgbpa7vft6744u

Power of d Choices with Simple Tabulation

Anders Aamand, Mathias Bæk Tejs Knudsen, Mikkel Thorup, Michael Wagner
2018 International Colloquium on Automata, Languages and Programming  
In this paper we suppose that the d hash functions are simple tabulation hash functions which are easy to implement and can be evaluated in constant time. Generalising a result by Dahlgaard et al.  ...  The interest is in the number of balls in the fullest bin after all balls have been placed.  ...  His functions require O(log n log log n) random bits and can be evaluated in time O((log log n) 4 ). We are not so concerned with the number of random bits.  ... 
doi:10.4230/lipics.icalp.2018.5 dblp:conf/icalp/AamandKT18 fatcat:dplopwtnybfifgbwwigo7j45py

Concurrent Hash Tables: Fast and General?(!) [article]

Tobias Maier, Peter Sanders, Roman Dementiev
2016 arXiv   pre-print
Since hash table accesses can dominate the execution time of the overall application, we need implementations that achieve good speedup.  ...  Our starting point for better performing data structures is a fast and simple lock-free concurrent hash table based on linear probing that is limited to word-sized key-value types and does not support  ...  Each element can still be found in constant time, because when looking for a certain key, it is imme-diately obvious in which table the corresponding element will be stored.  ... 
arXiv:1601.04017v2 fatcat:2da2yt5ze5bvhnzygjhb74t47a

Analysis of the SPV secure routing protocol

Barath Raghavan, Saurabh Panjwani, Anton Mityagin
2007 Computer communication review  
We find subtle flaws in the design of SPV which lead to attacks that can be mounted by 60% of Autonomous Systems in the Internet.  ...  In light of our analysis, we reexamine the need for constant-time signatures and find that certain standard digital signature schemes can provide the same level of efficiency for route authenticity.  ...  A constant-time signature scheme is a weaker version of a standard public-key signature scheme in which security is guaran-teed against an adversary who can acquire the signatures of only a small (constant  ... 
doi:10.1145/1232919.1232923 fatcat:5jxj37j5xnc4rft3mmij7davbu
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