Dubai, 20 November 29 November 2012
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VII.4 Packet descriptorPacket identification (PI) is the first function executed (by the DPI-FE) on an incoming packet (see clause VII.3). The identification is based on a lookup-key LPI_PD, see Figure VII.3, which itself contains elements (conditions) for application identification (abbreviated as LPI_AD) and optional flow identification (abbreviated as LPI_FD). 
NOTE 1 – Packet identification may be basically stateful or stateless. The identifiers may consequently contain elements for state information. NOTE 2 – The identifier spaces of Flow Descriptor and Application Descriptor are typically disjoint, but may also overlap in some DPI scenarios. NOTE 3 – Identification stages 1 & 2 represent the "Application Identification" and "Flow Identification" functions. The "Flow Identification" function is optional. If both identification functions, then any orders ... Figure VII.3 – Packet identification (as part of packet inspection) process,
The packet descriptor (PD) relates to the lookup-key used by the DPI-FE for identifying an incoming packet. Thus, the PD reflects the view of the DPI-FE as network element. From network perspective (“end-to-end”) will be application level conditions and (optionally) also the flow level conditions provided to the DPI-FE. Both application and flow descriptor spaces are typically disjoint because there should normally not any overlapping between application level conditions and flow level conditions (NOTE 1). Thus, the concept of a packet descriptor may be used in order to structure the descriptor used for DPI: PD = FD + AD FD = IPFIX-FD + Others-FD Others-FD = L2, L3 or/and L4 related information elements which are not (yet) in IPFIX registry (e.g., related to SCTP, DCCP) AD = NOT (FD) It may be noted that the Others-FD may disappear in future for the case that the extended IETF IPFIX registry would cover all elements required for DPI-based flow identification. NOTE 1 – Overlapping descriptor spaces are not excluded and actually are not any issue in practice. Effectively it could mean, e.g., the usage of the same Variable or even the same SimpleCondition in flow descriptor and application descriptor (see also clause VII.3) 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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