Slowly but surely, industry is discovering the need for programming languages, runtime environments and methodologies adapted to collaborative and distributed computing platforms. However, current distributed platforms, whether industrial or academic, are generally fragile with respect to resource exhaustion, and can provide, at best, ad hoc solutions to counter accidents or Denial of Service attacks. In this paper, we examine the problem of resource management in Erlang, that is providing services for distant use, while ensuring that untrusted third-parties using the services may not cause the exhaustion of memory, file handles or other limited resources. For this, we provide a formal semantics for a subset of Core Erlang, as well as a model of its library, and we provide a type system for formally proving robustness of services with respect to Denial of Service attacks.