The BBC is reporting that cellphone networks in London are coping adequately with higher-than-normal call volumes arising from the bomb incidents at lunchtime today. Cellphones have becomeas much a part of the critical national infrastructure as the "Plain Old Telephone System" (POTS). Wireless networks like their wired ancestors are designed with resilience in mind, including spare capacity, alternate routing and 'intelligent' real-time switching protocols. This is mostly to cope with the diurnal peaks and troughs of demand, partly for continuity through abnormal periods such as bombings, planned maintenance and unanticipated system failures.
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