[DNA] persistent TCP connection under 802.11 outage

[Kai Chen <kaichen@cs.uiuc.edu>]

Dear DNA members:

Sorry if this question has been asked before. I am trying to keep a TCP
connection persistent (e.g. SSH, FTP) over a 802.11 AP even after the
wireless link experiences temparary outage.

Currently the scenario goes like this:
1) 802.11 NIC detects loss of link;
2) OS tears down the interface and clears all the exisiting TCP states;
3) when the link is back, AP's DHCP likely gives the host the same IP;
4) however, the old TCP connections cannot continue due to lack of
socket states in the kernel.

Does anyone know how to solve (or approach) this problem under both
Windows XP and Linux? If the NIC's device driver can shield the link
outage from the upper layer, this problem should go away, correct?

Any pointers are greatly appreciated. Thanks very much in advance.

--
Kai Chen
Computer Science Department
Univ. of Illinois at Urbana-Champaign
Urbana, IL 61801, U.S.A.