Capacity of an infinite family of networks related to the diamond network for fixed alphabet sizes
Sascha Kurz
TL;DR
The article studies the 1-shot capacity of the parameterized network family $\mathcal{N}_s$ under adversarial errors on a subset of edges, focusing on fixed alphabet sizes $|\mathcal{A}|$. It proves a structural result that reduces 1-error correction to a covering problem, enabling exact computations and ILP-based determinations of $\sigma(\mathcal{N}_s,|\mathcal{A}|)$ for several small parameter choices. It also develops linear-programming (LP) bounds via Delsarte's method and Krawtchouk polynomials to tighten upper bounds, showing that a previously conjectured closed form is not generally valid for small alphabets. The work provides a framework for exact and bounded capacity analysis in adversarial network channels and lays groundwork for extending to other 2-level networks like families $A$ and $E$ and their variations.
Abstract
We consider the problem of error correction in a network where the errors can occur only on a proper subset of the network edges. For a generalization of the so-called Diamond Network we consider lower and upper bounds for the network's (1-shot) capacity for fixed alphabet sizes.
