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Según la Universidad de Bristol, la critografía abarca matemáticas pura, ciencias de la computación e ingeniería electrónica. Por ello y según su criterio, todo estudiante del doctorado en el campo de la criptografía (en dicha universidad) al final del primer año, debería ser capaz de responder al 90% de las siguientes preguntas:

Computer Engineering ([E])

1. What is the difference between the following?
   • A general-purpose processor.
   • A general-purpose processor with instruction-set extensions.
   • A special-purpose processor (or co-processor).
   • An FPGA.
2. What is the difference between a multi-core processor and a vector processor?
3. Estimate the relative computational and storage capabilities of
   • a smart-card
   • a micro-controller (i.e. a sensor node)
   • an embedded or mobile computer (e.g., a mobile phone or PDA)
   • a laptop- or desktop-class computer.

   Theoretical Computer Science ([F])

4. What is meant by the complexity class P?
5. What is meant by the complexity class NP?
6. How can we interpret NP as the set of theorems whose proofs can be checked in polynomial time?
7. How does randomness help in computation, and what is the class BPP?
8. How does interaction help in computation, and what is the class IP?
9. What are Shannon's definitions of entropy and information?

   Mathematical Background ([A,B])

10. What is the difference between the RSA and the Strong-RSA problem?
11. What are the DLP, CDH and DDH problems?
12. What is the elliptic curve group law?
13. Outline the use and advantages of projective point representation.
14. What is a cryptographic pairing?

    Basic (Practical or Deployed) Cryptographic Schemes and Protocols ([A])

15. Describe the key generation, encryption and decryption algorithms for RSA-OAEP and ECIES.
16. Describe the key generation, signature and verification algorithms for DSA, Schnorr and RSA-FDH.
17. Describe and compare the round structure of DES and AES.
18. Draw a diagram (or describe) the ECB, CBC and CTR modes of operation.
19. Describe the Shamir secret sharing scheme.
20. How are Merkle-Damgaard style hash functions constructed?

    Cryptographic Implementation Details ([A])

21. How does the CRT method improve performance of RSA?
22. How do you represent a number and multiply numbers in Montgomery arithmetic?
23. Write a C program to implement Montgomery arithmetic.
24. Describe the binary, m-ary and sliding window exponentiation algorithms.
25. Describe methods for modular reduction using "special" primes that define GF(p) and GF(2^n).
26. Describe the NAF scalar multiplication algorithm.

    Security Definitions and Proofs ([A,B,C])

27. What is the IND-CCA security definition for symmetric key encryption?
28. What is the IND-CCA security definition for public key encryption?
29. What is the UF-CMA security definition for digital signatures?
30. Roughly outline the BR security definition for key agreement?
31. Give one proof of something which involves game hopping
32. Outline the difference between a game based and a simulation based security definition.

    Mathematical Attacks ([A,B])

33. How does the Bellcore attack work against RSA with CRT?
34. Describe the Baby-Step/Giant-Step method for breaking DLPs
35. Give the rough idea of Pollard rho, Pollard "kangaroo" and parallel Pollard rho attacks on ECDLP.
36. What is meant by index calculus algorithms?
37. Roughly outline (in two paragraphs only) how the NFS works.

    Practical Attacks ([D])

38. What is the difference between a covert channel and a side-channel?
39. What is the difference between a side-channel attack and a fault attack?
40. What is usually considered the difference between DPA and SPA?
41. Are all side channels related to power analysis?
42. Look at your C code for Montgomery multiplication above; can you determine where it could leak side channel information?
43. Describe some basic (maybe ineffective) defences against side channel attacks proposed in the literature for AES.
44. Describe some basic (maybe ineffective) defences against side channel attacks proposed in the literature for ECC.
45. Describe some basic (maybe ineffective) defences against side channel attacks proposed in the literature for RSA.

    Advanced Protocols and Constructions ([A,B])

46. What is the Fiat-Shamir transform?
47. What does correctness, soundness and zero-knowledge mean in the context of a Sigma protocol?
48. What is the purpose and use of a TPM?
49. Describe the basic ideas behind IPSec and TLS.
50. What is the BLS pairing based signature scheme?
51. What is the security model for ID-based encryption, and describe one IBE scheme.
52. Pick an advanced application concept such as e-Voting, Auctions or Multi-Party Computation. What are the rough security requirements of such a system?

Fuente

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Realm Of The Mad God, es un juego al más estilo retro de los 80 multiplayer MUD. Con sólo jugar un rato podrás comprobar lo adictivo que llega a ser. No es complicado, pasearte por escenarios, matar todo tipo de criaturas, recolectar oro e incluso visitar mazmorras. Tiene un tutorial al comienzo y es gratuito, con opción de pago para por ejemplo, tener dos personajes.

Es como sería un juego online en los 80, si hubiera existido Internet ;)

Visto en BoingBoing.

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Antes de seguir, si no conoces WireShark aquí tienes un tutorial donde explica como empezar a utilizarlo. Una vez ya sabemos algo de este fantástico programa, en HowToGeek nos muestran 5 trucos para optimizar nuestro uso de la herramienta de captura de paquetes por excelencia. Voy a resumirlos para que veas el artículo completo por si te interesa:

1. Activar la resolución de nombres de red, en vez IP veremos los nombres de dominio.
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4. Usar WireShark en la línea de comandos, perfecto si queremos instalarlo en Linux o Windows (Server) sin interface gráfico.
5. Crear reglas ACL para un firewall, si quieres crear reglas en función del tráfico que detectas con WireShark , esta opción te genera los comandos que necesitas para poder hacerlo.

Si usas WireShark, no puedes perderte el artículo.