AAA and Network Security for Mobile Access: Radius, Diameter, EAP, PKI and IP Mobility

5.3. Seamless Mobility Procedures

Many people from different communities and backgrounds came to the IETF mobility community, all with the aim of finding a protocol that solves their mobility issues for a variety of applications. One of the useful things that IETF did was to define a set of terminology for the field of mobility [MOBTERM3753], to make sure everyone could express their requirements in a homogeneous manner. The list of handover types defined in that document is almost endless. However, we borrow a few definitions from there almost verbatim. These definitions help the reader understand the meaning of a seamless handover, since this term, due to countless number of misuses, has a very convoluted meaning:

• Fast handover: A handover that aims primarily to minimize handover latency, with no explicit interest in packet loss.

• Smooth handover: A handover that aims primarily to minimize packet loss, with no explicit concern for additional delays in packet forwarding.

• Seamless handover: A handover in which there is no change in service capability, security, or quality. In practice, some degradation in service is to be expected. The practical definition of a seamless handover is that other protocols, applications, or end users do not detect any change in service capability, security or quality, which would have a bearing on their (normal) operation. As a consequence, a handover that is considered seamless for a less demanding application might not be seamless for a more demanding ...