Multihoming is one of the most attractive features of stream control transmission
protocol (SCTP) aiming to make this prosperous transport scheme competitive in mobile
environments when the mobile hosts are equipped with multiple interfaces. The complementary
characteristic of the 3G universal mobile telecommunications system (UMTS) and wireless
local area network (WLAN) architectures motivates operators to integrate these two
successful technologies. Recently spreading wireless devices are increasingly provided
with multiple networking interfaces such enabling end-users to access internet services
using e.g., the WLAN's higher bandwidth wherever available, and connecting to the
UMTS network in other cases. This paper investigates the performance of multihomed
SCTP hosts through extensive experimental studies in such an integrated heterogeneous
environment. In order to do this, we designed and implemented a real native IPv6 UMTS-WLAN
testbed equipped with novel IPv6-based mobile technologies, such providing ideal conditions
for SCTP multihoming performance analysis. In this testbed architecture we analysed
numerous settings to measure the handover behaviour of the protocol in terms of handover
effectiveness, link changeover characteristics, throughput and transmission delay.
As our results show, accurate SCTP parameter setup can significantly decrease the
handover delay and eliminate the data transmission interrupts.
