Personal Server 2. Personal Server 1. PAN. Anonymizer Proxy Server 1. Anonymizer Proxy Server 2. Personal Area Network. Personal Area Network. People and Facilities in the Vicinity. Local Infra-structure Service.
People and Facilities in the Vicinity
Local Infra-structure Service
To further decrease the tractability, the pseudonym name should be alterable as the situation varies, e.g., when location changes or after certain time period
places or persons)
Real World Implementation
The ACAS project has developed a conceptual middleware solution to provide adaptive applications a simple access of distributed context information. This solution is built upon a number of components (named context entities), which interact with each other to form a Context Network to ensure a
desirable delivery of required information.
This poster addresses the issues toward realizing the proposed solution in the circumstance of real life, specifically about the issues of how to acquire context information from users with respect to their economical affordability and personal privacy
Building Personal Context-AwareSystems- Realizing ACAS infrastructure forpersonal useWei Li Computer and Systems Sciences DepartmentRoyal Institute of Technology
<BTDeviceaddress=" 08001719c4b6"type="Computer: Handheld PC/PDA“
service="Networking ,Object Transfer , Audio"timestamp="11147V1607531; Fri
Apr 29 01:40:07 CET 2005"presentFrom="11147V1607531; Fri Apr 29 01:40:07
<BTDeviceaddress="000ad91452ee"type="Phone: Smart phone"service="Limited
Discovery , Object Transfer"timestamp="11147V1607481; Fri Apr 29 01:40:07
CEST 2005"presentFrom="11147V1607481; Fri Apr 29 01:40:07 CEST
Figure 1.Central Personal Server: three types of context reports arrive from difference sources: continuous context updates from user’s familiar places (e.g., home and office); irregular context reports from user’s mobile devices when their connections are intermittent; and occasional context exchange with the unfamiliar people and environment in the user’s vicinity. Each place and user may have a central context entity which aggregates the associated information
and manages the access to it.
The server produces four types of events for subscribers (context consumers): appearing, appeared, disappeared and present.
Each event consists of a list of devices, the device name in the example is set with user’s IM account
 TeamSpace paper
Personal Server with IM URI: yahoo:firstname.lastname@example.org
SIP, MSN, Yahoo, Skype …
Local Infra-structure Service
Anonymizer Proxy Server
Name device with user’s Personal Server IM URI, like: yahoo:email@example.com
Dynamic associationwithBluetooth discovery
Figure 2. A Dynamically FormedContext Network with Anonymity Support: the personal server controls the access of personal data according to the user’s permission; while the Anonymous Proxy Server helps to decrease user tractability caused by context sharing. With these two components, the user is provided better
protection for their personal data.
By making more use of the available hardware and software technologies, we can lower the entry of context aware systems by encouraging and providing support for normal users to actively participate in constructing individual context systems which we hope will
have big impact for putting context system into real life