An analytical model of SPL-Feed-Forward OBS core nodes with mixed renewal and poisson process inputs.

Abstract

Tr÷íng ¤i håc Khoa håc, ¤i håc Hu2 Trung t¥m CNTT, V«n pháng TW £ng 3 ¤i håc HuŢ óm tắt. Vi»c t½nh to¡n hi»u su §t t¤i nót lãi trong m¤ng OBS èi vîi tr÷íng hñp luçng l÷u l÷ñng ¸n l Poisson ¢ ÷ñc • cªp kh¡ nhi•u. Trong b i b¡o n y, chóng taei thüc hi»n ph¥n t½ch vîi tr÷íng hñp luçng l÷u l÷ñng ¸n khaeng ph£i l Poisson (non-Poisson) m l qu¡ tr¼nh ¸n renewal (ùng vîi l÷u l÷ñng têng qu¡t GI). Vi»c k¸t hñp c£ hai luçng l÷u l÷ñng GI v Poisson công ÷ñc xem x²t vîi mët tr÷íng hñp °c bi»t cõa qu¡ tr¼nh ¸n mîi l qu¡ tr¼nh IPP (Interrupted Poisson Process). Chóng taei sû döng c¡c ph÷ìng ph¡p x §p x¿ ERT v GI º t½nh to¡n x¡c su §t tc ngh³n. K¸t qu£ ph¥n t½ch b ¶n trong mae h¼nh công nh÷ so s¡nh vîi mae h¼nh Poisson tr÷îc cho th §y t½nh óng cõa mae h¼nh ph¥n t½ch.

A Retrial Queueing model with FDL at OBS core node

“…In this model, we study the queuing model for FDL optical buffers take to consider the factors retrial of the bursts ( Figure 2). This is also different from analysis model in [6]. Without loss of generality, if we consider at output ( Figure.…”

“…1), for example, output (1 ≤ ≤ ), can be analyzed as follows: when the traffic arrives to the output port k, if there is a conflict, there are two possible cases: (i) The burst will be dropped due to the lack of wavelength resources (as well as sets CWC), called the lost burst, or (ii) burst will be delayed in the FDL with a certain period of time and continue to share wavelength resources at the epoch of exit from the FDLs (the burst will be dropped when all FDLs are busy or with probability (1 − ) or (1 − )), called burst delay. In this paper, as mentioned above, the difference between our proposed models versus the model in [6] to FDL (orbit queue) with probability ( ≤ 1) and retrial traffic (bursts come out from the FDL) when continuing the congestion at the output port can also re-circulate through one of the FDLs (2nd) with probability ( < 1).…”

“…The same as in [6], Markov model will also be used to evaluate the performance of OBS core nodes. The model is based on the following assumptions:…”

“…This corresponds to the state diagram in Figure 3, the blocking probability of each loss bursts and delay bursts can be calculated as follows [6]:…”

“…This is also different from the analysis model in the [4] and [5]. Accordingly, the characteristics of the FDL analyzed above We study new generic queuing model for FDL buffers based on model analyzed in [6] with consideration of the retrial factor, it means that the burst cannot be fed to the FDL when encountered congestion with a probability value θ or . A burst is called to be a retrial burst once it traverses one of the FDL.…”