We consider the problem of finding a smallest set of edges whose addition four-connects a triconnected graph. This is a fundamental graph-theoretic problem that has applications in designing reliable networks and improving statistical Ž Ž . . database security. We present an O n и ␣ m, n q m -time a
A characterization of weakly four-connected graphs
✍ Scribed by Tibor Jordán
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 106 KB
- Volume
- 52
- Category
- Article
- ISSN
- 0364-9024
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✦ Synopsis
Abstract
A graph G = (V, E) is called weakly four‐connected if G is 4‐edge‐connected and G − x is 2‐edge‐connected for all x ∈ V. We give sufficient conditions for the existence of ‘splittable’ vertices of degree four in weakly four‐connected graphs. By using these results we prove that every minimally weakly four‐connected graph on at least four vertices contains at least three ‘splittable’ vertices of degree four, which gives rise to an inductive construction of weakly four‐connected graphs. Our results can also be applied in the problem of finding 2‐connected orientations of graphs. © 2006 Wiley Periodicals, Inc. J Graph Theory 52: 217–229, 2006
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