asp.net mvc 2 - When to cache the results from a web service? -

in section web application information http://www.geonames.org/ ( web service method ) , http://data.un.org/ ( xml files stored on our application )

i'm new @ , questions are:

1. when cache information geonames ?
2. what method use cache ?
3. it ok if cache xml files or same performance ?

i use asp.net mvc 2 c#

caching way improve performance, consider it, if current performance not acceptable, otherwise there no need worry.

one way cache data set database table clob field, date time of when stored , of course fields identify object (such webservice parameters used obtain object).

you've decide policy expire old objects, instance set query run daily delete objects older week. example, can't tell how long cache, depends on size of data can keep , on how gets updated.

to questions in more detail:

.1. when cache information geonames ?

i'm not sure if understand correctly, normally: you'd value in cache, if it's found return cache, if it's not found service call , store result in cache.

.2. method use cache ?

i've explained way sql tables, use files, it's more complicated.

.3. ok if cache xml files or same performance ?

whatever decide cache, processed or unprocessed (xml) information, won't change performance point of view, since biggest delay fetching information network, not processing it.