A pump cylinder housing has a hollow cylinder and an end-side cover part, a threaded sleeve may be fixed on the outside of the hollow cylinder, at least three radially outward projections are connected to and distributed on the cover part periphery to the cover part and at least partly pass through recesses of the threaded sleeve. Methods, apparatuses, and systems are also presented for performing data decoding based on soft channel metrics derived from a channel using various iterative techniques. A timer is started in response to the established connection. An optical recording medium including a light-plasmon coupling lens.