SecurityFocus

DoS of LAN via D-Link switches Mar 29 2005 12:40PM
Frank Bures (lisfrank chem toronto edu) (1 replies)

RE: DoS of LAN via D-Link switches Mar 29 2005 07:15PM
David Gillett (gillettdavid fhda edu) (1 replies)

Re: DoS of LAN via D-Link switches Mar 29 2005 09:29PM
Tarmo Mamers (tarmo pobox com) (1 replies)

Re: DoS of LAN via D-Link switches Mar 30 2005 02:21PM
Neil Watson (bugtraq watson-wilson ca) (2 replies)

From: Frank Bures [mailto:lisfrank (at) chem.toronto (dot) edu [email concealed]]
Sent: Tuesday, March 29, 2005 4:41 AM
> In my opinion, a switch should be immune to this admittedly insane
> manipulation. Otherwise, one can DoS the entire network just
> by shorting
> two RJ-45 network outlets in one's office together.

I believe what you are describing is officially called a bridge loop. A
bridge loop occurs when a switch, or stack of switches are plugged into
themselves. The result is that the switches report the same MAC address
at multiple ports. The solution to this is called Spanning Tree
Protocol. STP is a set of algorithms that help switches remove
redundant MAC entries.

Reference:
http://www.oreillynet.com/pub/a/network/2001/03/30/net_2nd_lang.html

--
Neil Watson | Gentoo Linux
Network Administrator | Uptime 12 days
http://watson-wilson.ca | 2.6.11.4 AMD Athlon(tm) MP 2000+ x 2

[ reply ]

Re: DoS of LAN via D-Link switches Mar 30 2005 10:19PM
Scott Nelson (sbn thermeon com)

Re: DoS of LAN via D-Link switches Mar 30 2005 10:04PM
Joel Maslak (jmaslak antelope net)