The interface still feels as snappy as the original, but the number of requests made to the server is substantially reduced, particularly when users type in quick bursts.
Long run economic constraints include declining oil production and exports and pressure on water supplies caused by rapid population growth, industrial expansion, and increased water pollution.
Limitations: Difficulty of quickly and reliably discriminating between hostile forces and neutral or friendly parties or objects, such as civilians, cows, trees, and tractors.
Johnson said there would inevitably be more potential cases and anyone entering the country with flu-like symptoms would be examined "very, very quickly".