An Internet-style approach to wireless link errors

Abstract

Wireless links differ from traditional ‘wired’ links in two ways that challenge the existing Internet. On wireless links packet loss or corruption due to transmission errors is not rare, which calls into question the standard Internet assumptions that transmission errors should be corrected by transport-level protocols at end systems and that end-to-end packet loss typically indicates network congestion. Also, the severity and location- dependent nature of these errors calls into question the meaning of ‘fair’ scheduling, per-flow quality of service, and even looser notions such as service level agreements, when applied to wireless links. An important question is whether the two unique problems posed by wireless links can be successfully addressed within the standard Internet architecture, as opposed to requiring new transport protocols designed specifically for wireless links or requiring wireless links to ‘fix up’ the operation of specific end-to-end protocols. We provide experimental evidence that a combination of protocol-blind link-level local error control, which lessens the damage, and error-sensitive link scheduling, which ensures sensible outcomes in response to link capacity loss, provides a good operating environment while adhering to traditional Internet design practices. Copyright © 2001 John Wiley & Sons, Ltd.