A comparison of in-band and out-of-band transport options for signaling

摘要

Signaling protocols for GMPLS networks have been standardized and are now being implemented. Most switch vendors allow for signaling messages to be carried over in-band signaling channels as well as through out-of-band networks. In this paper, we compare these two signaling transport options. In carrying out this analysis, we allow for both software-implemented signaling protocol processors, as is common in most off-the-shelf switches today, as well as hardware-accelerated signaling protocol engines. Our research project on hardware-accelerated signaling is in support of a service concept in which dynamically provisioned high-speed end-to-end circuits are used for single file transfers. In this application, signaling message loads will be extremely high since call holding times will be short. For such a usage, we need a signaling transport solution that minimizes message transfer times. Therefore this question of in-band versus out-of-band signaling transport is relevant to our research. Our analysis shows that with hardware-accelerated signaling engines, in-band signaling is the better option, while in a network with only software signaling processors, the out-of-band solution is better.