Addressless: A New Internet Server Model to Prevent Network Scanning

TL;DR

This paper introduces the addressless server model that enhances server security by preventing network scanning through a separation of server modules and dynamic address generation, without requiring client or network modifications.

Contribution

The paper proposes a novel addressless server architecture that isolates the main server, prevents scanning, and supports flexible load balancing without client or network changes.

Findings

Prevents main server from being scanned

Maintains high availability and load balancing

Imposes slight performance overhead

Abstract

Eliminating unnecessary exposure is a principle of server security. The huge IPv6 address space enhances security by making scanning infeasible, however, with recent advances of IPv6 scanning technologies, network scanning is again threatening server security. In this paper, we propose a new model named addressless server, which separates the server into an entrance module and a main service module, and assigns an IPv6 prefix instead of an IPv6 address to the main service module. The entrance module generates a legitimate IPv6 address under this prefix by encrypting the client address, so that the client can access the main server on a destination address that is different in each connection. In this way, the model provides isolation to the main server, prevents network scanning, and minimizes exposure. Moreover it provides a novel framework that supports flexible load balancing, high-availability, and other desirable features. The model is simple and does not require any modification to the client or the network. We implement a prototype and experiments show that our model can prevent the main server from being scanned at a slight performance cost.