Seasons of Syn

SYN-dog: Sniffing SYN Flooding Sources

This paper presents a simple and robust mechanism called SYN-dog to sniff SYN flooding sources. We install SYN-dog as a software agent at leaf routers that connect stub networks to the Internet. The statelessness and low computation overhead of SYN-dog make itself immune to any flooding attacks. The core mechanism of SYN-dog is based on the protocol behavior of TCP SYN—SYN/ACK pairs, and is an ...

TCP SYN Flooding Defense

The TCP SYN ooding denial-of-service attack pointed out a weakness of then-current Internet protocols. There have since been many proposals to defend against SYN ooding, some requiring signiicant changes to TCP. Several solutions attempting to resolve the TCP weakness are now generally available. We document these existing solutions and qualitatively compare them. We reene the analysis of the r...

syn,syn-15,17-Di-2-naphthyl­hexa­cyclo­[10.2.1.13,10.15,8.02,11.04,9]hepta­decane deuterochloro­form monosolvate

The main molecule of the title compound, C(37)H(36)·CDCl(3), is a hydro-carbon with two naphthalene segments attached to opposite ends of a rigid norbornylogous spacer with an overall structure that is approximately C-shaped. The dihedral angle between the naphthalene ring planes is 9.27 (7)°. The cleft that exists between the naphthalene rings is large enough that the compound crystallizes wit...

The Seasons of Life

Resisting SYN Flood DoS Attacks with a SYN Cache

Machines that provide TCP services are often susceptible to various types of Denial of Service attacks from external hosts on the network. One particular type of attack is known as a SYN flood, where external hosts attempt to overwhelm the server machine by sending a constant stream of TCP connection requests, forcing the server to allocate resources for each new connection until all resources ...