Скачиваний:
50
Добавлен:
20.06.2019
Размер:
50.48 Mб
Скачать

316

K.W.S. Morrison

18.4.5.2  Acceleration of Cryptographic Operations

Cryptographic operations, such as RSA key operations, also see benefits from hardware acceleration. This hardware may integrate higher-level protocol optimization (such as SSL acceleration), FIPS-compliant cryptographic algorithms, and Hardware Security Module (HSM) protection of keys (nCipher, Sun, Safenet). HSM modules in particular find wide application in military and intelligence markets.

FIPS-compliant software cryptographic libraries are widely available (RSA, Certicom), and drawing on the benefits of elastic deployment can offset cryptographic optimizations.

Protection of key material is an open problem for clouds. In private clouds, it is conceivable to interface with a physical HSM shared between virtual images. In public clouds, a software-based secure key store is the only alternative. This has inherent risk as virtual images may leave behind residual disk images on termination, potentially exposing key stores to scavenging and brute force decryption.

18.4.6  Transport Content Coding

Message content compression can be economically advantageous between onpremises computing facilities and cloud providers. HTTP includes content coding [8], but only on the response message; this is insufficient for bidirectional SOAP messaging (or highly parameterized REST requests). A similar nonstandard model, also leveraging algorithms like zlib, gzip, and compress (or dictionary substitutions of common SOAP idioms), could extend to requests. However, the challenge is that PEPs at either end must synchronize compression parameters out of band, or utilize proprietary negotiation protocols.

18.4.7  Security Challenges in the Cloud

The great challenge with PEPs deployed in the cloud – and indeed, in all distributed computing – is the secure propagation of identity context between tiers. Privacy and integrity may act in support of this fundamental issue.

18.4.8  The PEP Air Gap

The virtual PEP deployed in the cloud acts as a policy air gap between the external Internet and internal applications. It deliberately breaks transport semantics into ingress and egress segments, kept separate and mediated through policy. This affects

Соседние файлы в папке CLOUD COMPUTING