Traffic Control in a Linux, Multiple Service Edge Device

Authors

Abstract

Small and medium size networks with access to the Internet are each day more common in SOHO (Small Office/Home Office) environments, comprising domestic and small to medium size organizations. Inherent to the spread of these networks is the search for small access devices that allow the connection to the Internet in a very user friendly way but with a growing number of offered services, comprising basic IP functionalities (e.g., DNS, DHCP, SMTP and NAT), security and traffic control services. Traditionally, these services are available in dedicated, proprietary, and often-patented devices, with complex integration and high cost. More recently, new products appeared in the market that integrate several services in a single device, as is the case of 6WINDGATE from 6WIND [1], Access Point from Lucent Technologies [2] and ERX Edge Router from Juniper Networks [3]. However, these products still present some complexity at management and still have medium to high cost. To overcome an open space in the market, Critical Software and the LCT Lab from University of Coimbra are developing a Linux, multi-service edge device, aiming the offering of basic and advanced IP services at low cost and with trivial management requirements. This paper presents one of the key components of this Edge Device, the traffic control system. Particularly, it presents a solution for the DiffServ-based modeling of upstream and downstream traffic in a single Linux router that is also an authentication, NAT (network address translation), firewall, service provider and application gateway machine. Performance tests of the control traffic system and correspondent analyses of the results conclude the paper.

Keywords

Resource Management; Congestion Control; QoS; Edge Device; Linux

Subject

Traffic Control

Conference

International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networking (NEW2AN'04), February 2004