The huge commercial success of mobile telephony, phenomenal growth of mobil
e and Internet users, and emerging popularity of IP-based multimedia applic
ations are the major driving forces behind third-generation (3G) evolution.
3G will bring wireline applications, both data and multimedia, into wirele
ss environments. It will operate on IP-based infrastructures to provide wid
er service access capability. However, current IP is designed for data appl
ications with a single service class, best-effort. Therefore, it is insuffi
cient to support real-time applications that require diverse quality of ser
vice (QoS). Although IP can provide greater service flexibility, in terms o
f spectrum efficiency and QoS, it is not the most appropriate choice in wir
eless environments. In order to support real-time applications in wireless
IP networks, measurement-based admission control (MBAC) is considered. We c
onsider two admission criteria, reservation and priority. The system perfor
mance is measured in terms of new call blocking and hand-off call dropping
probabilities with three different levels of user mobility: low, moderate,
and high level of mobility. Considering the delay-tolerant nature of real-t
ime applications in wireless IP networks, the effect of delay tolerance on
the overall system performance is also investigated. We discuss the suitabi
lity of MBAC in wireless IP networks by comparing its pros and cons with tr
aditional parameter-based schemes, and then describe its procedures. Next,
we discuss simulation details, and present simulation results with discussi
ons. We compare new and hand-off traffic performance with strictly policy-b
ased and policy and traffic characteristic-based admission control schemes.
In the conclusion, we briefly discuss the effectiveness of MBAC and its ro
le in 3G and forthcoming 4G networks.