Method for upgrading a core section (120, 120') of a packet switched mobile network (100, 100') intended to provide packet data services to user equipment, the method including: a) calculating an active users parameter, wherein the active users parameter is a ratio between a maximum signaling transaction amount (MSTA) managed by nodes (SGSN, GGSN, MME, SGW, PGW) of the core section and a number of active data connection established between user equipment and the packet switched mobile network (100, 100'); b) measuring a number of user equipment attached to the packet switched mobile network (100, 100'), and calculating a corresponding activity parameter giving an indication of how the maximum signaling transaction amount managed by the nodes (SGSN, GGSN, MME, SGW, PGW) of the core section is distributed among said user equipment attached to the packet switched mobile network (100, 100'); c) calculating a forecasted number of user equipment which potentially will be able to attach to the network in a future predetermined period, wherein said calculating a forecasted number of user equipment is based on either interpolating existing data relating to the diffusion of user equipment in preceding periods or a number of user equipment which will be available in the market in the future predetermined period d) calculating a signaling traffic estimation by multiplying the active users parameter, the activity parameter and the forecasted number of user equipment to each other, and e) increasing the signaling capacity of the core section (120, 120') if the calculated signaling traffic estimation is higher than a threshold, wherein said increasing the signaling capacity of the core section (120, 120') comprises at least one among: - adding nodes to the core section (120, 120'), and - increasing the resources to be assigned to the nodes of the core section (120, 120'). a) calculating an active users parameter, wherein the active users parameter is a ratio between a maximum signaling transaction amount (MSTA) managed by nodes (SGSN, GGSN, MME, SGW, PGW) of the core section and a number of active data connection established between user equipment and the packet switched mobile network (100, 100'); b) measuring a number of user equipment attached to the packet switched mobile network (100, 100'), and calculating a corresponding activity parameter giving an indication of how the maximum signaling transaction amount managed by the nodes (SGSN, GGSN, MME, SGW, PGW) of the core section is distributed among said user equipment attached to the packet switched mobile network (100, 100'); c) calculating a forecasted number of user equipment which potentially will be able to attach to the network in a future predetermined period, wherein said calculating a forecasted number of user equipment is based on either interpolating existing data relating to the diffusion of user equipment in preceding periods or a number of user equipment which will be available in the market in the future predetermined period d) calculating a signaling traffic estimation by multiplying the active users parameter, the activity parameter and the forecasted number of user equipment to each other, and e) increasing the signaling capacity of the core section (120, 120') if the calculated signaling traffic estimation is higher than a threshold, wherein said increasing the signaling capacity of the core section (120, 120') comprises at least one among: - adding nodes to the core section (120, 120'), and - increasing the resources to be assigned to the nodes of the core section (120, 120'). - adding nodes to the core section (120, 120'), and - increasing the resources to be assigned to the nodes of the core section (120, 120').