att_abstract={{The volume of Internet traffic over 3G wireless networks is sharply rising.
In contrast to many Internet services utilizing replicated resources
(e.g., content distribution networks), the current 3G standard
architecture employs
hierarchical routing, where all user data traffic goes through a small
of aggregation points using logical tunnels.
In this paper, we investigate the potential system inefficiency and
performance issues due to
the interplay of the two systems.

We first identify a number of aspects affecting system inefficiency and
service performance and then quantify the impact by analyzing trace data
obtained from a large-scale 3G network and a CDN provider.
We find that extra packet headers used for hierarchical routing
result in significant byte overhead (around 6\%).
We also find that the detour due to hierarchical routing can cause a
packet to travel
extra distance by up to 1627km on the average case, which based on
our data analysis, corresponds to around 45.4\% increase in round-trip
Furthermore, we identify a pathological case due to DNS caching when a
device switches between wireless technologies.
In our measurement study on the Internet, we find that this issue can cause
up to an order of magnitude throughput degradation (0.9Mbps vs. 10.8Mbps).
We also study how to achieve performance improvement by deploying
system resources more strategically.}},
	att_authors={sl1858, zg2325},
	att_copyright_notice={{The definitive version was published in ITC 2011. {{, 2011-09-06}}{{, http://i-teletraffic.org/fileadmin/ITC23_files/Copyright_form_ITC2011.pdf}}}},
	att_tags={GTP,  CDN,  detour routing},
	author={Seungjoon Lee and Zihui Ge and Wei Dong, University of Texas},
	institution={{ITC 2011}},
	title={{3G Meets the Internet -- Understanding Performance Issues due to
Hierarchical Routing in 3G Networks}},