Clock recovery based on packet inter-arrival time averaging

Aweya, James; Montuno, Delfin Y.; Ouellette, Michel; Felske, Kent

doi:10.1016/j.comcom.2005.10.019

Cited by 13 publications

(6 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This estimate can be used as the clock reference in a PLL (at the receiver) which locks the frequency of the voltage-controlled oscillator (VCO) to the transmitter's bit rate as illustrated in Figure 3. The receiver clock recovery circuit can use a digitally controlled oscillator (DCO) instead of a VCO (see Figure 4) [11]. The function of the DCO is similar to that of a VCO in an analog PLL.…”

Section: Packet Inter-arrival Time Averaging Methodsmentioning

confidence: 99%

Analysis of a clock‐recovery technique for circuit emulation services over packet networks

Aweya

Montuno

Ouellette

et al. 2007

Int J Communication

Self Cite

View full text Add to dashboard Cite

SUMMARYOne important requirement of circuit emulation services (CES) over packet networks is clock synchronization and timing distribution among the nodes. CES depends on reliable and high-quality timing for operations. In the time division multiplexing (TDM) world, whether plesiochronous digital hierarchy (PDH), synchronous digital hierarchy (SDH) or synchronous optical network (SONET) based, timing and synchronization is inherent in the design of the network. However, when timing critical services such PDH and SDH/SONET are carried over packet network (e.g. IP, Ethernet, etc.), the timing element is lost and has to be carried across the packet network by other means. A well-known and widely implemented technique for clock recovery in CES is one that is based on packet inter-arrival time (sometimes called time difference of arrival) averaging. The technique is very simple to implement but provides good performance only when packet losses and packet delay variation (PDV) are very low and well controlled. This technique has been extensively analysed through simulations but has not been fully characterized analytically with correlated traffic in the literature. In this paper, we provide a full analytical examination of this well-known clock recovery technique. We analyse the effects of correlation of the delay variation in the traffic stream on the quality of the clock recovered by a receiver. We prove analytically that, for a general input process, high correlation of the delay variation produces a large variance of the recovered clock.

show abstract

Section: Packet Inter-arrival Time Averaging Methodsmentioning

confidence: 99%

Analysis of a clock‐recovery technique for circuit emulation services over packet networks

Aweya

Montuno

Ouellette

et al. 2007

Int J Communication

Self Cite

View full text Add to dashboard Cite

show abstract

“…Fig. 2 shows a digitally-controlled oscillator (DCO)-based implementation of asynchronous SCFR schemes as suggested in [4], where the estimated clock frequency ratio directly drives a DCO to generate a desired source clock.…”

Section: A Regression Through the Origin (Rto) Modelmentioning

confidence: 99%

“…Existing SCFR schemes extract the information on the source clock frequency from packet interarrival times (e.g., [3], [4], [5]), buffer levels -often combined with packet interarrival times -(e.g., [6], [7]), or timestamps (e.g., [8], [9], [10]). Because the interarrival times and the buffer levels cannot provide the information on the source clock frequency in case of aperiodic packet streams, only timestamp-based schemes can be applicable to the asynchronous SCFR through aperiodic packet streams.…”

Section: Introductionmentioning

confidence: 99%

Asynchronous Source Clock Frequency Recovery through Aperiodic Packet Streams

Kim

2013

IEEE Commun. Lett.

View full text Add to dashboard Cite

Abstract-We consider the most general case of source clock frequency recovery (SCFR) in packet networks, i.e., asynchronous SCFR through aperiodic packet streams, where there is neither a common reference clock nor any relation between packet generation intervals and a source clock frequency. We formulate the problem of asynchronous SCFR with timestamps as a linear case of regression through the origin (RTO) and propose two schemes, one based on recursive least squares (RLS) method and the other based on simple heuristics of cumulative ratio of interarrival and interdeparture times, which provide better estimates of the source clock frequency with faster convergence than conventional phase-locked loop (PLL)-based schemes.

show abstract

“…Upon receiving this information, the host decreases its sending rate, so congestion can be avoided or mitigated. Current AQM algorithms can be mainly cataloged into following types: queue-size-based [3,4], traffic-rate-based [5][6][7], the combination of queue-size-based and rate-based [8], control-theory-based [9][10][11][12], etc. In fact, each AQM algorithm includes two parts: one part estimates the incipient congestion and the other part makes dropping decision based on the estimation.…”

Section: Introductionmentioning

confidence: 99%

A novel adaptive traffic prediction AQM algorithm

Guo

Gao

et al. 2010

Telecommun Syst

View full text Add to dashboard Cite

In the Internet, network congestion is becoming an intractable problem. Congestion results in longer delay, drastic jitter and excessive packet losses. As a result, quality of service (QoS) of networks deteriorates, and then the quality of experience (QoE) perceived by end users will not be satisfied. As a powerful supplement of transport layer (i.e. TCP) congestion control, active queue management (AQM) compensates the deficiency of TCP in congestion control. In this paper, a novel adaptive traffic prediction AQM (AT-PAQM) algorithm is proposed. ATPAQM operates in two granularities. In coarse granularity, on one hand, it adopts an improved Kalman filtering model to predict traffic; on the other hand, it calculates average packet loss ratio (PLR) every prediction interval. In fine granularity, upon receiving a packet, it regulates packet dropping probability according Z. Na ( ) School to the calculated average PLR. Simulation results show that ATPAQM algorithm outperforms other algorithms in queue stability, packet loss ratio and link utilization.

show abstract

Clock recovery based on packet inter-arrival time averaging

Cited by 13 publications

References 14 publications

Analysis of a clock‐recovery technique for circuit emulation services over packet networks

Analysis of a clock‐recovery technique for circuit emulation services over packet networks

Asynchronous Source Clock Frequency Recovery through Aperiodic Packet Streams

A novel adaptive traffic prediction AQM algorithm

Contact Info

Product

Resources

About