| 摘要 |
A telecommunications network including a plurality of terminals 1,11 is disclosed, each having a presence status. A presence server 40 monitors the presence status of each of the terminals 1,11. The terminal 11 is operable to invite the terminal 11 to publish its presence status to the first terminal 1 via the presence server 40. In response to the invitation the presence server 40 is operable to seek acceptance from the second terminal 11. The presence server 40 stores security data respective to each of the terminals 1,11. In response to the acceptance by the terminal 11, the presence server 40 provides the first terminal 1 with the security data of the terminal 11. This is used to establish a secure communication session between the terminal 1 and the terminal 11. The security data may, for example, be a public key of the terminal 11. The security data may be a Host Identity, or a Host Identity Tag. An extension to Presence Information Data Format is disclosed for transmitting the security data between the terminals 1,11 and the presence server 40. |
