The increasing proliferation of mobile devices with Internet access contributed to clarify some important limitations of TCP/IP stack regarding mobility, multihoming, traceability and security. In its original design, Internet IP addresses were overloaded to simultaneously support host identification (ID) and location (Loc). As a consequence, application functionality can be affected when IP addresses are changed to update mobile nodes location. This dual functionality causes many problems in the current Internet, especially in supporting mobility. To deal with this limitations several solutions based on the idea of ID/Loc splitting have been proposed. In this position paper we present and compare some of them, summarizing their main features and limitations. We also identify opportunities and challenges for future research in the area as well as expected impacts/relations with other Future Internet aspects. www.inatel.br/iwt

1. Host Identification and Location
Decoupling: A Comparison of
Approaches
Bruno Magalhães Martins
Antônio Marcos Alberti
© Antônio M. Alberti 2011

2. Outline
1. Motivation
2. Approaches for Host ID/Loc Splitting
3. Comparison
4. Conclusion
© Antônio M. Alberti 2011

3. Motivation
 Current IP address → identification + location (overload).
 This limitates → mobility, multihoming, scalability, etc.
 Future networks need to separate identifiers (ID) from locators
(Loc) → the so called ID/Loc splitting.
 Why ID/Loc splitting? → To move hosts without “loss of identity”.
© Antônio M. Alberti 2011

4. Approaches for Host ID/Loc Splitting
 Mobile IP
 HIP (Host Identity Protocol)
 LISP (Locator ID Separation Protocol)
 MILSA (Mobility and Multihoming Supporting Identifier Locator
Split Architecture)
 Akari
 MCP (Mobility Control Protocol)
© Antônio M. Alberti 2011

5. Mobile IP
 Idea:
 Two IP addresses:
 Home-address → static; works as an ID for app. layer;
 Care-of-address → dynamic; according to node’s location.
 Two components:
 Home-agent → atributes home-address; mantains mapping to current
location;
 Foreign-agent → atributes care-of-address; informs home-agent.
 Identification:
 Home-Address
 Location:
 Care-of-Address
© Antônio M. Alberti 2011

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© Antônio M. Alberti 2011

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 New namespace between network and transport
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8. LISP (Locator ID Separation Protocol)
 Idea:
 Address mapping between edge and core IP networks; IP over
UDP over IP; two IP addresses:
 EIDs (Endpoint Identifiers) → persistent; used as an ID;
 RLOCs (Routing Locators) → used to locate edge routers.
 Two components:
 ITR (Ingress Tunnel Router) → maps EIDs on RLOCs;
 ETR (Egress Tunnel Router) → maps RLOCs on EIDs.
 End Host Identification/Location:
 EIDs
 Edge Router Identification/Location:
 RLOCs
© Antônio M. Alberti 2011

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© Antônio M. Alberti 2011

10. MILSA (Mobility and Multihoming Supporting Identifier Locator Split Architecture)
 Idea:
 Separation of trust relations, called domains, and the relations of
connectivity, called zones;
 Separation between signaling and data plan.
 RZBS (Zone Bridging Realm Server) - provides dynamic mapping
between IDs and locators.
 Identification:
 Assigned at domain level;
 Location:
 Assigned at zone level;
© Antônio M. Alberti 2011

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12. Akari
 Idea:
 New namespace between network and transport layers: ID Layer.
 Identification:
 By name and/or by identifier (ID) obtained by hash function;
 Legible and unique local names;
 Includes hierachical topology information in global names;
 Location:
 IP, non-IP, post-IP.
© Antônio M. Alberti 2011

13. Akari
Identification
Local Name
+IMS Domain Name
Global Name
Hash Function
ID
Locator
Location
Source: Akari Prpject
© Antônio M. Alberti 2011

14. MCP (Mobility Control Protocol)
 Idea:
 New namespace between network and transport layers: HID-based
Communication Layer.
 Identification:
 HIDs (Host Identifiers) → hash function of host’s proprietary public
key.
Application/Transport
 Location:
 Two protocols: HID-based Communication
 ADP (Access Delivery Protocol);
 BDP (Backbone Delivery). Network Delivery (ADP/BDP)
© Antônio M. Alberti 2011

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16. Conclusion
 ID/Loc splitting is one of the most important solutions to address
some of the current Internet limitations.
 Legible names are important to people.
 Approaches need to support post-IP designs.
 We need to evaluate the introduction of new layers.
 We need more holistic and integrated designs:
 To cover relationships among identifiers, names, locators and
routing.
 To improve security and trust.
 To integrate with information ID/Loc splitting.
© Antônio M. Alberti 2011