Chapter 13. Proxies and Checksums

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This chapter, aptly number 13, examines two unlucky features of conducting NSM on real networks: proxies and checksums. The term proxy refers to a piece of network infrastructure that some companies use to observe, control, and accelerate Internet usage. The term checksum, in the context of this chapter, refers to an error detection mechanism offered by the Internet Protocol (IP). This chapter describes some ways to cope with the problems caused by each of these features in operational environments.


Web proxies are especially popular in corporate environments. One type of web proxy is tuned to handle traffic ...

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