India has approved installation of NarusInsight machines at ISPs, so it is anybody's guess how prevalent these are here.
A single NarusInsight machine can monitor traffic equal to the maximum capacity (10 Gbit/s) of around 39,000 DSL lines or 195,000 telephone modems. But, in practical terms, since individual internet connections are not continually filled to capacity, the 10 Gbit/s capacity of one NarusInsight installation enables it to monitor the combined traffic of several million broadband users.According to a company press release, the latest version of NarusInsight Intercept Suite (NIS) is "the industry's only network traffic intelligence system that supports real-time precision targeting, capturing and reconstruction of webmail traffic... including Google Gmail, MSN Hotmail, Yahoo! Mail, and Gawab Mail (English and Arabic versions)."
It can also perform semantic analysis of the same traffic as it is happening, in other words analyze the content, meaning, structure and significance of this entire traffic, as it is happening.
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