【導讀】filtration(packetfiltering)andauthentication(authentication)technology,itsvalidity

　　

【正文】 ble of prevent intercept, fit design to transmission not confidential data up to with IP correspondence. There into, AH message preamble field include： 1. Next Header 2. Length 3. Security Parameters Index 4. Sequence Number 5. Authentication Data IPSec protocol future vista Today, information super highway ratio ever before big city bulk, but it too be confronted with EVERLARGER security menace, hence versus muscle Tnumber suffer every last node hardware security sexual demand in course of on the increase up. It was one postmortem take problem into consideration that but, versus heap work equipments drawing Design whereas character, security. Us need for versus whence, when and on what occasion enrolls safety properties precede reconsider in as well to. For the moment have got three strain primary means could above work hardware equipments enroll security function in. First strain no more will principals means namely treat coherency with one coprocessor importance loaf work processing unit or currency. It was eke one security get base up at the back of work processing unit done out that second strain means. It was should encryption circuit integration at maintain know clearly transfer speed and farthest dam know clearly 12 chip area back with work processing unit analogous chip suffer, thereby at work processing unit suffer join know clearly security function at the same time that third strain means. Wherefore, high integration density should inspire IPSec ‘develop with rush. 3 Follow on IP agreementIPv6 Change of IPv6 Change incarnate infra five importance aspect among IPv6： (1) spread address (2) predigestion head format (3) Tone toward spread and option 39。support up (4) Stream tag (5) Both identity authentication and secrecy 1. 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Other kind of selection scheme suffer, hopbyhop option spread head oblige clad path last every last node big city get said head field done to. instance, each Router must at dispose IPv6 toe enroll option, therewith differ, IPv6 suffer do with option plus at separate spread head suffer in. top hopbyhop option by definition design to micrometer IP fold (jumbo lotus) in. contain jumbo lotus. Wherefore, this with need for above tight warp ultra each node big city versus option precede inspect to. 14 4. Stream Clad dispose could not so much him WRAPT differ, therefore at any rate, toward their dispose out sail, for Router dispense with versus each toe among enfold height of row imitate dispose among it was unaltered that at IPv6 suffer, versus possession WRAPT approximately parity treat, this purport each WRAPT big city yes by mi