The present invention discloses a switching apparatus, a switching apparatus group, a data transmission method, and a computer system, and pertains to the field of computer technologies. The switching apparatus includes: a selection circuit module, a SERDES module, and a scheduling module. The selection circuit module establishes at least (n−1) static links with each of n modes, and any two static links that are connected to the selection circuit module and that belong to different nodes are connected to each other. The SERDES module is disposed on a static link connected to the selection circuit module. The scheduling module establishes connections to the selection circuit module and each of the n nodes. The selection circuit module further establishes at least one dynamic link with each of the n nodes.