A peer-to-peer relay network, comprising: a plurality of N peer systems (1105 A-D) in which each peer system is either a participant of a spectator and the peer-to-peer network includes at least one participant and at least one spectator; wherein: each peer system (1105 x) in said peer-to-peer relay network is connected to a number of other peer systems (1105 y) in said peer-to-peer relay network that is less than or equal to a connection limit; said connection limit is greater than or equal to 2; said connection limit is less than or equal to N-2; each peer system in said peer-to-peer relay network is configured to relay data to peer systems connected to that peer system according to a set of one or more relay rules; a participant is configured to generate data to be relayed in said peer-to-peer relay network and a spectator is configured to relay data generated by a participant; spectator peer systems are not authorised to generate and send new data to be relayed throughout the peer-to-peer network; the data has associated information identifying the origin peer system that generated said data from which it is determined whether the origin peer system is a participant or a spectator; and the data is relayed if the origin peer system is a participant and is not relayed if the origin peer system is a spectator. a plurality of N peer systems (1105 A-D) in which each peer system is either a participant of a spectator and the peer-to-peer network includes at least one participant and at least one spectator; wherein: each peer system (1105 x) in said peer-to-peer relay network is connected to a number of other peer systems (1105 y) in said peer-to-peer relay network that is less than or equal to a connection limit; said connection limit is greater than or equal to 2; said connection limit is less than or equal to N-2; each peer system in said peer-to-peer relay network is configured to relay data to peer systems connected to that peer system according to a set of one or more relay rules; a participant is configured to generate data to be relayed in said peer-to-peer relay network and a spectator is configured to relay data generated by a participant; spectator peer systems are not authorised to generate and send new data to be relayed throughout the peer-to-peer network; the data has associated information identifying the origin peer system that generated said data from which it is determined whether the origin peer system is a participant or a spectator; and the data is relayed if the origin peer system is a participant and is not relayed if the origin peer system is a spectator. each peer system (1105 x) in said peer-to-peer relay network is connected to a number of other peer systems (1105 y) in said peer-to-peer relay network that is less than or equal to a connection limit; said connection limit is greater than or equal to 2; said connection limit is less than or equal to N-2; each peer system in said peer-to-peer relay network is configured to relay data to peer systems connected to that peer system according to a set of one or more relay rules; a participant is configured to generate data to be relayed in said peer-to-peer relay network and a spectator is configured to relay data generated by a participant; spectator peer systems are not authorised to generate and send new data to be relayed throughout the peer-to-peer network; the data has associated information identifying the origin peer system that generated said data from which it is determined whether the origin peer system is a participant or a spectator; and the data is relayed if the origin peer system is a participant and is not relayed if the origin peer system is a spectator.