Presence service in ims

Anotace: The presence in contrast to instant messaging (IM) is a dynamic user profile that is visible to others and shares information about itself. It can be represented through statuses that are perceived by other users of the service. Status includes personal information, information about the device, location, type of terminal device or preferred way of contacting the user (messages / video / call). This information is always linked to the person concerned. The presence service uses the SIP protocol, which manages presence information and determines how it is used (for example, who can see the presence information and to what extent) and is designed for a wide range of applications. [1] [2]