# Guidelines towards Information-Driven Mobility Management
## 3 Mobility Management Functional Aspects
The MAP controls the main functionality of mobility management, namely handover management, traffic offloading, location management, bindings and address translation, _Quality of Service (QoS)_, and forwarding policies. Learning from the evolution of prior solutions, and from the extension required to support additional features such as simultaneous mobility, it is relevant to consider that any future mobility management architecture needs to be designed already having in mind that any node on the network can move. Furthermore, it needs to consider that, due to the way the Internet is evolving, these functional entities can reside in any type of device, even embedded ones. To further debate on how such support can be provided, the functional design of today's solutions can be split into different blocks [11]:  
* _Identification._ For IP-based solutions such as _MIPv6_, this would correspond to the mapping of a network interface to an IPv6 address; in SIP, this would be a mapping between an URI (known address) and one or multiple IPs; and in HIP, this corresponds to a Locator Id. * _Database control._ Control functionality is usually provided by a central entity, which assists in a quicker mapping of the different identifiers. Usually, this functionality is part of the MAP entity. * _MAP selection._ This is a control function that assists in a better deployment of MAPs having in mind to improve reachability of MNs. In centralised solutions, such selection is often performed in a static and centralised way. * _Binding registration._ This is a control plane function that signals the first registration of a MN in a mobile system. For instance, in MIP, it is the first Binding Update message sent to a MAP or to a CN. In SIP, it is the REGISTER message sent to the Registrar server. Figure 1: High-level representation of mobility management main entities, the MN, the CN, and the MAP. The MAP is often co-located with different devices, including end-user devices. * _Binding update._ This is a control plane function that signals an update a record in the Identification control. Binding updates are used when the unique identifier of a device changes. * _Routing or forwarding._ It is the process of intercepting the packets destined to the known-address, encapsulating them with the real-address, and forwarding them. In MIP, this is performed by the MAP or by the first access router in the path _(Home Agent, HA)_. In SIP, this process can be performed by an external element, for instance, an RTP translator. * _Handover negotiation._ This is the process taken when the device has its identifier changed, to allow active communications to be held with the least disruption. In MIP, the handover negotiation may be anticipated with, e.g., mechanisms such as the Fast Handover extension. SIP does not implement any anticipation, performing a re-negotiation after the connection between peers is lost. * _Resource management._ This is the process that assists in guaranteeing the quality of a connection while devices perform a handover. Most solutions as of today do not integrate QoS support, recurring to external mechanisms to provide such support. * _Mobility anticipation._ It is the procedure of performing a handover before an active connection experiences a break. For instance, anticipation is partially supported in MIPv6 via the extension Fast Handovers for MIP. * _Security and privacy._ It refers to every security mechanism to assure the integrity of both data and channel for the active communication, as well as for the signalling of the mobility management system. Current centralised solutions require external security support to protect data, channel, as well as involved signalling. The evolution of mobility management towards information-centricity (and, hence, better service support) requires looking into these different functional blocks, and understanding whether or not they can be simplified.