Poster: Rough Edges for IPv6 in VPNs
Yejin Cho and John Heidemann
USC/Information Sciences Institute
Citation
Yejin Cho and John Heidemann. Poster: Rough Edges for IPv6 in VPNs. Proceedings of the ACM Internet Measurement Conference (Nov. 2025), 1048–1049. [DOI] [PDF] [alt PDF]
Abstract
How do VPNs interact with IPv6? Our poster shows that VPNs often leak IPv6 traffic, failing to provide the promised privacy, and VPNs often prefer IPv4, even though IPv6 is available and working. These results use new data from a website for IP identification, coupled with experiments on specific VPN software. We identify the fraction of v6 traffic leaked, and find the root-cause of IPv6 de-preferencing in interactions between address selection in OSes and VPNs.Bibtex Citation
@inproceedings{Cho25b,
author = {Cho, Yejin and Heidemann, John},
title = {Poster: Rough Edges for IPv6 in VPNs},
booktitle = {Proceedings of the ACM Internet Measurement Conference},
year = {2025},
sortdate = {2025-11-27},
pages = {1048--1049},
month = nov,
project = {ant, internetmap, bripod},
jsubject = {topology_modeling},
jlocation = {johnh: pafile},
doi = {https://doi.org/10.1145/3730567.3768612},
keywords = {ipv6, vpn, leaking private addresess, depreferencing},
url = {https://ant.isi.edu/%7ejohnh/PAPERS/Cho25b.html},
pdfurl = {https://ant.isi.edu/%7ejohnh/PAPERS/Cho25b.pdf},
myorganization = {USC/Information Sciences Institute},
copyrightholder = {authors}
}