Photon Netw Commun (2010) 19:74–80
A novel shared-link protection algorithm with correlated link
failure probability for dual-link failure
Xu Jun · Chang HuiYou · Xu Chang · Yi Yang
Received: 11 May 2009 / Accepted: 16 August 2009 / Published online: 28 August 2009
© Springer Science+Business Media, LLC 2009
Abstract For the dual-link failure problem of the Auto-
matic Switched Optical Network, the paper analyzes the reli-
ability of conventional shared-link protection (SLP) based on
correlated link failure probability and differentiated reliabil-
ity, and a novel differentiated shared-link protection (DSLP)
algorithm is proposed. The results show that, compared to the
conventional SLP algorithm, DSLP not only can satisfy the
speciﬁc requirements of users but also yields better perfor-
mance with respect to the number of interrupted lightpaths
subject to a dual-link failure.
Keywords ASON · Shared-link protection · Dual-link
failure · Correlated link failure probability · Differentiated
The Automatic Switched Optical Network (ASON) is con-
sidered as one of the key technologies for the next generation
network, as it possess high resource utilization, ﬂexible cir-
cuit allocation, quick and effective network protection, and
recovery as well as sound network scalability. The important
function of the ASON control plane can support a quick and
effective network protection mechanism and therefore can
enhance network survivability.
However, the conventional protection design is concen-
trated on a single-link failure [1,2] and the shared-protection
path method [3,4]. With increasing network size and a more
complex network structure, the possibility of a dual-link fail-
ure is greatly increased. The occurrence of a dual-link failure
X. Jun (
) · C. HuiYou · X. Chang · Y. Ya ng
School of Information Science and Technology, Sun Yat-Sen
University, Guangzhou 510275, China
cannot be ignored. Therefore, the dual-link failure protec-
tion design has raised a problem that must be considered.
At present, some literature has studied dual-link failure pro-
tection [5–7], but most of them just focus on shared-path
protection (SPP) because it provides better resource utili-
zation than other protection methods. One objective of the
ASON-based protection schemes is rapid reaction to fail-
ures and short recovery times. Protection schemes can be
generally divided into path and link based techniques. For
path-related protection mechanisms a failure is being pro-
cessed at the path endpoints, whereas for link-based pro-
tection mechanisms this processing is performed at the link
end nodes. Obviously, link protection reduces the commu-
nication requirement as compared with path protection, thus
providing fast recovery.
In this paper, based on correlated link failure probability
(CLFP), we analyze the reliability of protection path for con-
ventional shared-link protection (SLP) method subject to a
dual-link failure, and propose a new algorithm for surviving
dual-link failures, called differentiated shared-link protection
(DSLP). Finally, simulation experiments prove the effective-
ness of the algorithm.
2 Conventional SLP problem formulation
2.1 Network model
In order to accurately describe the mathematical model of
the conventional SLP problem, assuming G for the network
topology, the following symbol definition is given:
: Number of wavelengths on a link.
N : Set of nodes in network G.
L: Set of links in network G.