Dubai, 20 November 29 November 2012
III.4 Notes to Staged Process Models
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III.4 Notes to Staged Process ModelsThe two processing stages for DPI policy conditions, the scanning function and analysing function, may lead to an overall 3-stage processing model. Such a staged model may be motivated by similar processing models in other computer areas, e.g., the translation of computer programming source code in executable instructions by interpreters or compilers, because there are a lot of commonalities between policy enforcement processing (of packet traffic) and the compilation processing (of programming languages), from perspective of a runtime environment. The two stages of lexical and syntactical analysis in the parser model of a compiler are very similar to the processing model of (DPI policy) conditions by the two stages of DPI scan function and DPI analyser function. Appendix IV
(This appendix does not form an integral part of this Recommendation) IV.1 IntroductionThis appendix provides complementary information on Policy Specification Languages (PSL), also known as Policy Expression Language (PEL) of Filter Specification Language (FSL). The definition of a PSL is out of scope of this Recommendation. However, the question of PSLs is related here to multiple network interfaces, like a control plane policy control interface between a remote policy decision function and the DPI node function and a management plane policy management interface between network (policy) management functions and the DPI node function. There are thus inherent protocol requirements across multiple, different network interfaces concerning the “transport9 of policy rule sets” down to the DPI-FE (see also Figure IV.1). IV.2 PSL for Policy Control and Policy Management InterfacesFigure IV.1 provides a summary of a typical network scenario. The policy operations by the control plane and network plane addressing both the same objects of the policy enforcement path in the user plane. Thus, an aligned PSL usage across all relevant interfaces would be crucial for efficient DPI node functions. 
Figure IV.1 – Policy Specification Language (PSL) – PSL for Policy Control and Policy Management Interfaces Directory: wp-content -> uploads -> 2012 2012 -> The Case Against the nypd’s Quota-Driven ‘Broken Windows’ Policing What Is It? 2012 -> Aa and na members Dying from Tobacco 2012 -> [Baby Crying] 01: 04 [Ching 2012 -> Unit Name / Nom de l’unité uic / ciu dates 2012 -> What We Owe Jehovah’s Witnesses 2012 -> Oceans Challenge Badge 2012 -> Canadian cycling olympians 2012 -> Greg landry, june olkowski and tom lysiak 2012 -> William goldman 2012 -> Does translocation and restocking confer any benefit to the European eel population? A review Download 1.36 Mb. Share with your friends:
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