1. A method performed within a network element, for changing software on both control and line cards of the network element, while the network element services sessions, the method comprising the steps of: virtually partitioning a plurality of control cards and a plurality of line cards of the network element into a virtual partition A and a virtual partition B, with each of the virtual partitions having a plurality of cards including at least one control card and at least one line card; redistributing sessions currently serviced by the cards of the virtual partition A to the cards of the virtual partition B; after the step of redistributing the sessions from the cards of the virtual partition A to the cards of the virtual partition B, changing software on, at least, the at least one line card of the virtual partition A, while the cards of the virtual partition B service sessions including the sessions redistributed from the cards of the virtual partition A; after the step of changing the software on at least the at least one line card of the virtual partition A, redistributing sessions currently serviced by the cards of the virtual partition B to the cards of the virtual partition A; after the step of redistributing the sessions from the cards of the virtual partition B to the cards of the virtual partition A, changing software on the at least one line card of the virtual partition B and the at least one control card of the virtual partition B, while the cards of the virtual partition A service sessions including the sessions redistributed from the cards of the virtual partition B; and after the step of changing the software on the at least one line card of the virtual partition B and the at least one control card of the virtual partition B, eliminating the virtual partitions and redistributing a portion of the sessions currently serviced by the cards of the virtual partition A to the cards of the virtual partition B, whereby the software may be changed on both the control and line cards of the network element, while the network element services the sessions, so that service interruption due to the changing of the software reduced.