The search for a suitable micromobility protocol which will inter-work with Mobile IP in 3G mobile networks has been the subject of intense research. Several proposals have been analyzed and comparisons carried out [1]. Cellular IP is a strong contender to take the seat as the chosen micromobility protocol, and its performance has been characterized mainly with Columbia IP Micromobility Software (CIPMS) under diverse scenarios. Previous analysis have considered generic TCP and UDP traffic. In the work presented here, a Cellular IP based 3G network model is developed, and services (voice, and web) are represented after probabilistic behaviours to conform, respectively, to a GSM coder, and web content comprised of packets, objects, and pages. In this way a more accurate knowledge of Cellular IP performance can be obtained.