As far as i know there is no specific pre- requisite for the bandwidth or network link capacity for infra servers. It is generally done with a HTTP request. May be it will be taking a long time for the datasynchronization, suggested is to place the synchronizations in the off- peak hours.
As Manohark stated, there is no specific requirements other than support for HTTP over the connection. The data is downloaded from the Server to the Remote servers and cached there. The download happens over HTTP.