novel algorithm in activation process of gpon networks

Novel Algorithm in Activation Process of GPONNetworks

Tomas Horvath, Petr Munster, Michal Jurcik, and Miloslav Filka

Abstract—Passive optical networks are dominating access net-works around the world due to its their economical aspect,bandwidth, and penetration. It is necessary to deal with spec-ification of these networks. The article deals with a transmissionconvergence layer of a Gigabit passive optical network, especiallythe activation process for ONUs. When the blackout affects allONUs in the network, all ONUs need to be resynchronized withOLT but the current algorithm affects that for higher value ofONUs synchronization after a couple of minutes. We proposeda novel algorithm for an ONU activation time with the sameframe structure and state machine, which are defined in the mainspecification. We verified the proposed algorithm by simulationand compare results for the current and novel algorithms. Ourresults confirm that it is possible to achieve the better time upto nineteen times lower synchronization time in comparison withthe current algorithm.

Index Terms—GPON, Transmission Convergence layer, simu-lation, algorithm.

I. INTRODUCTION

Nowadays, the PONs (Passive Optical Networks) are widelyused around the world. The basic classification of the passiveoptical networks is in accordance with a transferring proto-col: Ethernet frame or ITU (International TelecommunicationUnion) encapsulation method. The PONs according to IEEE(Institute of Electrical and Electronics Engineers) are domi-nating in Asia, especially the EPON (Ethernet PON) standard.However, in this article we deal only with the ITU standards,particularly with the GPON (Gigabit PON) approved by ITUin 2003 standard because this standard is dominating in theEurope.

The European Union requires at least 30 Mb/s of thebandwidth to each household until 2020. It is necessary todeal with the gigabit passive optical networks because thistechnology is mature and widely used in the Czech Republicby ISPs (Internet Services Providers). However, ISPs can usenewer technology called XG-PON (Next Generation PON)they use the GPON technology due to its mature. Fig. 1 showsa roadmap of the ITU standards for PONs.

The principle of the PON networks can be explained by thefollowing terms: ONU (Optical Network Unit), OLT (OpticalLine Termination) and ODN (Optical Distribution Network).

Manuscript received September 25, 2015; revised December 31, 2015.Research described in this paper was financed by the National Sustainabil-

ity Program under grant LO1401, and SIX CZ.1.05/2.1.00/03.0072. For theresearch, infrastructure of the SIX Center was used.

Authors are with Department of Telecommunications, Brno University ofTechnology, Brno, Czech Republic (E-mails: [email protected], [email protected], [email protected], [email protected]).

~2010 ~2015 Year [-]

Cap

acit

y[G

b/s

]

Fig. 1. ITU standards roadmap [1].

In general, the OLT is located in the CO (Central Office) andONU is located in the customer part of the network, everythingelse between OLT and ONU is called ODN (optical fibres,splicing, splitters, and connectors). In general, the communica-tion slots are allocated by the TDM (Time Division Multiplex)for GPON but newer standards are based on combinationof the TDM and WDM (Wavelength Division Multiplex),especially XG-PON and NG-PON2 (Next Generation PONsecond generation). The description of two latest standards isout of the scope of this article.

In the following part, we describe the GPON in moredetails. The GPON standard has specification of physical andTC (Transmission Convergence) layers. The physical layeris specified by the ITU-T G.984.1 document where the mostimportant part for the ODN is described. In general, the docu-ment specifies the split ratio, bandwidth, wavelengths etc. It isnecessary to define two types of the GPON networks: standardand long reach networks. We deal with a typical networkwith ODN length of 20 km, split ratio at least 1:64 (up to1:128), and 1480–1500 nm for downstream and 1260–1360 nmfor upstream wavelengths, specified by [2]. Furthermore, thebandwidth can be allocated in symmetric or asymmetric mode:symmetric mode uses 1.24416 or 2.48832 Gb/s, asymmetricmode defines 1.24416 or 2.48832 Gb/s for downstream and0.15552, 0.62208, and 1.24416 Gb/s for upstream direction.A specification of the TC layer is more complicated but themost important part is an initialization process for each ONUin ODN. Specification of the TC layer will be described laterin the chapter.

204 JOURNAL OF COMMUNICATIONS SOFTWARE AND SYSTEMS, VOL. 11, NO. 4, DECEMBER 2015

1845-6421/12/8414 © 2015 CCIS

FESB

Typewritten Text

Original scientific paper

The current algorithm of ONU activation process allows toregister only the single ONU in one period. That is the reason,why the last ONU can be connected after tens of secondsdue to actual behaviour of algorithm. We proposed a novelalgorithm for ONU activation process. The main contributionof this paper is the algorithm which reduces the total time ofactivation process with the current frame structure and statemachine.

The rest of this paper is structured as follows. Section 2gives an overview of some other related works. Section 3describes the GPON technology and ONU activation process.Section 4 shows a designed model of current and novel algo-rithms. Section 5 discusses the achieved results and Section 6concludes the paper.

II. RELATED WORKS

Since 1995 many standards of passive optical networks havebeen developed. In GPON, the downstream is transferred viabroadcast for each ONU, only ONU with the same identifiersis able to read the frame. The upstream direction is transmittedvia unicast. There are many works which deal with thephysical and TC layers of the GPON.

The authors in [3] describe the TC layer for the XG-PONnetworks. They focus on the comparison of frame structuresfor the GPON and XG-PON from the point of view of up-stream and downstream efficiency. The results presented XG-PON networks as much more efficiency for the downstreamand upstream transmission. On the other hand, the XG-PONis newer standard of the passive optical network with the newframe structure. The authors do not compare the initial processin the GPON and XG-PON networks.

The work [1] dealt with the TC layer for the XG-PONnetworks. We explained the collision issues in a registrationprocess, the influence on the equalization delay on initializa-tion process, and the influence of a refractive index on the RTD(Round-Trip Delay) in the XG-PON networks. In general, wedid not deal with the initial process of the ONU when firstconnecting into the PON.

The paper [4] analyse security issues of the GPON net-works. We focused on the security because the GPON net-works have security issues with the key establishment. Inthis establishment key or parameters for the key computingare transferred as a plain text. In general, the GTC (GPONTransmission Convergence) frame has a complicated structureand it is not quite easy to decode the frame. However, thereare some companies which can provide an analyser for GPONand XG-PON networks. That is the reason why it is necessaryto solve these security issues.

Further, the paper [5] explored redesign of Metro-AccessNext Generation PON. They reached 100 km with redesigningof the TC layer. However, the authors did not assume thedifferent propagation delay because OLT is able to correct thevarious length of the ODN by an equalization delay. Moreprecisely, the equalization delay is considered up to 60 km ofODN.

The article [6] provided stability and delay analysis of theEPON registration protocol. They used the Markov model and

Discrete-Time Markov Chain for the registration process sim-ulation. The authors verified the influence of the registrationdelay using simulation model. Further, the EPON uses thedifferent registration process in comparison with GPON.

The work [7] compared the economic aspects betweenthe GPON and EPON networks. As was mentioned before,EPON is dominating in Asia and GPON is dominating inEurope. They consider 100 000 customers in ISP’s networkand compared which standard provides the higher bandwidthto each customer. The GPON standard is more efficient whenthe customer wants to have a higher bandwidth (with loweramount of OLTs the GPON standard is able to provide higherbandwidth that EPON).

Further, the paper [8] introduced capacity and delay analysisof Next-Generation PON. They took stock of the huge PONwith different standards (EPON, GPON, and XG-PON) witha numerical and simulation models. These simulations did notconsider the initial phase where it is necessary to solve thevarious delay of each packet. On the other hand, it is not moreprobable that the one ODN will contain the various types ofstandards and their upgrades.

The authors [9] dealt with link utilization and comparison ofEPON and GPON access network cost. They compared EPONand GPON frame structures and DBA (Dynamic BandwidthAllocation). The analysis showed that GPON systems usesthe link capacity more efficiently than EPON systems [9]. Onthe other hand, the GPON transceivers are more expensive incomparison with the EPON transceiver.

The goal of this paper is to enhance the initial phaseof first ONUs connection into the ODN. We compare thestandard algorithm with our novel technique. In other words,the main contribution of this work is a novel technique toestablish a connection between OLT and ONU with the sameframe structure and keeping a state machine for establishmentconnection.

III. ONU ACTIVATION PROCESS

When the ONU is connected into the PON for the firsttime, it is necessary to go over the activation states. The firststate in activation process is the initial state (O1) which is thesimple state because the ONU needs to receive 3 GTC framesfor downstream synchronization. When the ONU powers up,LOS (Loss of Signal) and LOF (Loss of Frame) are asserted(set to 1). Then the first frame is received, the LOS/LOFare cleared (set to 0). In detail, the OLT consecutively sendsthe downstream frames containing the PSBd (Physical Syn-chronization Block downstream) and Psync fields and has fixlength (125µs). The ONU unit needs to pass over the partialstates of the initial phase. First, the ONU has to receive atleast two frames with the same Psync value. In other words,the receiving of the frames with the exactly same Psync fieldis called Hunt state. The frames have to be analysed bit bybit because the ONU is looking for the Psync pattern. Oncea correct Psync pattern is found, the ONU transition into thePre-sync state and sets a counter (N) to value 1 [10]. The ONUcontinues with inspection of each of all receiving frames butwith the following frames is the counter N incremented. It

T. HORVATH et al.: NOVEL ALGORITHM IN ACTIVATION PROCESS OF GPON NETWORKS 205

is necessary to define the parameter M because it representsthe number of renewal. In other words, when M is set to5, it means the ONU needs to receive 5 frames with thecorrect (exactly same) Psync field. On the other hand, whenthe single frame contains different value in Psync pattern, theONU moves back to the Hunt state. Then the exact valueof frames defines with M are received, the ONU moves toSync state which is the final state of the Initial state with thecorrect pass. Note, if the parameter M is set, for example,to 3 instead of 5 (the minimum value is 2), ONU reachesthe Sync state earlier but if the ONU does not receive 3correct frames it moves back to a Hunt state. The ONU movesto the Standby state (O2) [10]. Nevertheless, the ONU hasbeen synchronized but the ONU does not know the networkparameters (delimiter value, power level, and pre-assigneddelay). In other word, Upstream Overhead message has to betransmitted three times by OLT. After that, the ONU configuresthe parameters and moves to Serial Number state (O3). TheOLT sends the serial number request to ONU. The ONUanswers with serial number ONU PLOAM (Physical LayerOperation, Admission, and Maintenance) message and waitsto answer with Assign ONU-ID PLOAM message which issending three times by the OLT. The Assign ONU-ID messagesets the ONU-ID for direct addressing in the network andhas to be received before the timer TO1 expires (10 seconds).After processing, the ONU with assigned ONU-ID moves toRanging state (O4). The Ranging state has the most importantfunction, since the ONUs are located in a various lengths fromthe OLT it is necessary to compute an equalization delayseparately for each ONU. In other words, the equalizationdelay eliminates the various distances between ONUs andOLT with keeping the synchronization of the time slots forthe ONUs. The control unit can calculate time equalizationdelay by the following equation (1) [10]:

Teqd = T1490,i +RspT imei + EqDi + T1310,i= T1490,i

n1310+n1490

n1490+RspT imei + EqDi

where RspT ime is the response time (µs), EqDi is theestimation (pre-assigned delay by OLT) of the equalizationdelay for the ODN length, n1310 represents the group velocityrefractive index for 1310 nm in the ODN, n1490 represents thegroup velocity refractive index for 1490 nm in the ODN. Fromthe fraction with group velocities the index correction factorcan be called. It can be expressed as (2) [10]:

T1490,i = (Teqd−RspT imei − EqDi)n1490

n1310 + n1490

Substituting into the expression for the receive instance ofGTC frame N we obtain the equation (3) [10]:

TrecvN,i = TsendN,i + T1490,i

The full formula of eq. (4) is [10]:

TrecvN,i = TsendN + Teqd[

n1490

n1310+n1490

]OLT

−

(EqDi +RspT imei)[

n1490

n1310+n1490

]ONU

The ONU sends Serial Number ONU message to OLT andwaits for an answer. The answer is the Ranging Time message

750125 125 750 750 ...

O1 O2

BWmapempty

+SN req

QW+

SN ONU Assigned ONU-IDOLT normal

operation stateOLT normal

operation stateOLT normal

operation state

UpstreamoverheadPLOAMPsync

0

Turn ONONU time

125 125 125 14 125 125 125236 250

125 125 125 111

14 us z duvodu odelsani zprávy, ze to drive byt

nemuze, protože by se to rpekryvalo s odpovedmi. SN

number ONU.

O3

Psync

… 750 236 202t [µs]

Range reqBwmapempty

QW+

SN ONU Rnd = 0Ranging time

PLOAMOLT normal

operation state

62

125 125 125 63

O4

125 750125125

Fig. 2. Activation process based on current algorithm.

t1

t2

tn

Splitter 1:X

ONU1

ONU2

ODN

OLT

ONUn

Fig. 3. The simulation topology implemented in Matlab.

with re-calculates the equalization delay (the ONU has onlypre-assigned delay) which is set up by ONU. Then, the ONUmoves to Operational state (O5) which is the last state for thebidirectional communication. A sequence of the frames foreach state is shown in Fig. 2.

IV. SIMULATION SET UP

We used the Matlab (without Simulink R©) software with ownimplementation of GPON network (by m-file functions), es-pecially the TC layer model. The physical layer is representedby the length of an optical fibre in order to evolve a velocityof propagation and various split ratios (from 1:16 to 1:128).The attenuation class B was selected for our simulation model.More precisely, we did not consider the higher split ratio than1:128. In general, for higher split ratios the specification isnot allowed [10] and the total attenuation specified for ClassB is not observed. Our GPON simulation model contains theOLT, ONUs, and ODN. We consider the longest ODN for thesimple simulation topology which is shown in Fig. 3.

The simulation models were created for the current andthe novel algorithms. The following text describes the cur-rent algorithm. The variable nONU represents the value ofONUs after the splitter from 2 to 128 values. The parameterMaxDistance provides the distance of ODN. In general, whenwe define 20 (km), it means that our model generates ran-dom length for each nONU variable which is save for theequalization delay calculation. Constant fd means the frameduration (125µs) and delay variable adds a time when thecounter curTime overflows timer TO1. As was mentioned


before, only single ONU can be activated after the receiving ofSerial Number request because ONUs wait for locally randomdelay (0–48µs) with answer in the real network. The OLTanswers to the first receiving Serial Number ONU message.Our simulation model has no pre-assigned delay and theparameter M is set to 2. In the Initial phase (O1), Hunt staterequires only two frames with the correct Psync field to enterStandby state (O2). It is an optional parameter, the ISP canset up this parameter by their consideration. The current flowshown in Fig. 2 repeats each second.

We proposed the novel algorithm for activation processwhich reduces activation time. As first, there is a generation ofarray of n-ONUs at random distances from OLT up to 20 km.Then the array is sorted in ascending order due to the distance(this is done because in the best case the closer ONU willrespond in the shortest time and the OLT will choose ONUthat sends an Assign ONU-ID message first). After that there isa loop for all ONUs which calculates the delay of connectingONUs to the network. For the first ONU it is:

• 21 × fd – where ONU synchronizing in the upstreamdirection received Upstream Overhead PLOAM to set thenetwork parameters and responds to Serial Number ONUmessage.

• 16×fd – to assign ONU-ID, responds to Ranging Requestwith Serial Number ONU and receives Ranging TimePLOAM to set equalization delay.

• 3× fd – when ONU enters Operational State (O5). Thisdelay is optional and is used only for OLT to let ONUbe ready for transmission

The total time is 40 × fd (5ms) to connect the first ONUto the network. The OLT then sends another Assign ONU-ID message after 403 frames (50.375 ms) then the next closestONU is connected in 403 × fd + 3 × fd (52.750ms). Thisrepeats 19 times until the OLT is able to connect 20 ONUs in1 second. Note that there is a 2-frame space between the lastONU in this cycle and the first ONU in the next second cycleso the joining of the ONU at the beginning of each second isdelayed by 250µs. The OLT is able to connect 128 ONUs inapproximately 7 seconds so this setup should be useful whenthe OLT is rebooted. After that it can operate in normal state.

Nowadays, ISPs use activation process which is defined in[10] but manufacturers can change some unspecified fieldsof messages because they are undefined. It is only recomen-datation which causes the compatibility issues. Our proposedalgorithm should be implemented independent (because weuse exactly same messages type and format). More detailsabout our proposed algorithm are described in Fig. 4. Theinitial phase is same as current algorithm defined in [10]but the main disadvantage is smaller number of total registerONUs in the same time. Note that many parameters such asPreassigned delay and ONU-ID are transferred in broadcastmode. The ONU processes all downstream frames while look-ing for own serial number or ONU-ID if is already assigned.The OLT should operate normally for at least 750µs whenit transmits by broadcast Upstream Overhead and AssignedONU-ID PLOAM messages as recommended in [10]. In ourimplementation we consider that the OLT waits exactly 750µs

before transmitting another PLOAM message(s) but vendorsmay set longer delay which will cause slower activationof ONU(s). We also consider transferring of exactly sameparameters but with more grants for ONU at the same time.The main goal is to speed up an activation process afterblackout scenario because each ONU needs to be registered byOLT again. Blackout causes that customers are not able to usepaid services until their ONU is activated again. For example,when we consider 1024 ONUs, up to tens of minutes or unitsof hours is needed but with our algorithm the registrationprocess of the same amount of ONUs can be reduced up tounits of minutes.

PLOAMoverhead

SN_reqOLT

SNOONU

Assign ONU-IDRange req

OLTSNO Rnd0–48 µs

Ranging timeOLT

O5

OLT normaloperation50.375 ms

WaitingforOLT

O1 O2 Success Received

TO1starts

TO1 expired

O4

ONU turn ON

PsyncM1–1

Fail

Success

Fig. 4. State machine of proposed algorithm.

The simulation models had been divided into two scenar-ios, with the current and novel algorithm. The results weredisposed by split ratio with the same algorithm. In general,our model had the TC layer for ONU and OLT, optical fiber(represented the velocity of propagation delay – calculatedfrom c and refractive index n), and length was generatedfrom the range (1–20 km). The simulation results with currentalgorithm for split ratios (1:16 and 1:32) are shown in Fig. 5.

In Fig. 5 dependence of split ratio on activation time pro-posed by our implementation in Matlab is depicted. We didnot change state machine and messages format defined in [10].In general, the current algorithm is able to register singleONU in one algorithm cycle. In the worth case, the lastONU in blackout scenario was connected approximately after33 seconds. On the other hand, the real networks never containonly 32 ONU at single OLT ports due to the economical aspectof network. The second scenario was for the higher split ratios(1:64 and 1:128) which had the results depicted in Fig. 6.

In the second scenario the results reached the higher values.When we consider the standard OLT with 4, 8 or 16 portsto splitters and ODN that means eight times higher totaltime for the last ONU (applies for the OLT with singleCentral Processor Unit). In other words, our results need to bemultiplied by ports number of OLT. In the best case, the lastONU will be connected after 500 s (4× fd = 500 s) or 2 000 sin the worth case (16× fd = 2 000 s). That is the reason whywe proposed the novel algorithm for activation process withkeeping the frame structure and state machine.


0 5 10 15 20 25 30 35

0

5

10

15

20

25

30

35

ONU (–)

Tim

e(s)

Activation timing for 16/32 ONUs

16ONUs32ONUs

Fig. 5. Activation process for 16/32 ONUs in blackout scenario usingalgorithm defined in [10] (without changes).

0 20 40 60 80 100 120 140

0

20

40

60

80

100

120

140

ONU (–)

Tim

e(s)


64ONUs128ONUs

Fig. 6. Activation process for 64/128 ONUs in blackout scenario usingalgorithm defined in [10] (without changes).

We simulated the same scenarios with our proposed algo-rithm. At first, Fig. 7 depicted the results for the lower splitratios (1:16 and 1:32).

We reached approximately seventeen times lower time incomparison with the current algorithm. The last ONU willbe connected after ∼2 seconds when we talk about 32 ONUswith the same frame structure and state machine. The proposedalgorithm does not require any special hardware because wemodified a quite window. The quite windows are normallyused in the current algorithm (see Fig. 2). The OLT with thequite window has time to process answer to ONUs and shouldprepare the following messages. The second scenario withhigher split ratios (1:64 and 1:128) provided more interestedresults.

The last simulation of activation process is shown in Fig. 8.The time ∼7 s for the last ONU is shown in Fig. 8. It is not thefinal time because we consider singe port used at OLT but weare able to estimate time for the best and worth case. In thebest case, the OLT has 4 ports. Each of them has 128 ONUs (inother words split ratio is 1:128). In worth case we obtained∼28 s for one port and ∼112 s for 4 ports, respectively. In

0 5 10 15 20 25 30 35

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

ONU (–)

Tim

e(s)


16ONUs32ONUs

Fig. 7. Time of activation process for 16/32 ONUs in blackout scenario usingour algorithm (with changes).

0 20 40 60 80 100 120 140

0

1

2

3

4

5

6

7

ONU (–)

Tim

e(s)


64ONUs128ONUs

Fig. 8. Time of activation process for 64/128 ONUs in blackout scenariousing our algorithm (with changes).

comparison with the current algorithm we decreased nineteentimes the total time in activation process. For example, whenthe OLT has issue and needs to be replaced, with our algorithmthe subscribers have a connection time from the seconds tominutes compared to the current algorithm where it takes fromtens of seconds to tens of minutes.

V. CONCLUSION

This paper deals with novel activation process in GPON.A modification of the current algorithm causes that we areable to minimize the time requirements. For the business orVIP clients it is necessary to serve the best SLA (ServiceLayer Agreement) at ODN. Therefore, the current algorithmis not able to assure the expeditious reaction. We proposed thenovel algorithm which reduces nineteen times the total timeof activation process for last ONU in ODN. In other words,we are able to connect more ONUs at the same time. Usingof proposed algorithm can be implemented in GPON and XG-PON only with a modification of the sequence of the frames.

In future work, we would like to implement our solutioninto real OLT and analyse the performance of the proposed


solution.

REFERENCES

[1] Lukas Koci, Tomas Horvath, Petr Munster, Michal Jurcik, and MiloslavFilka.Transmission Convergence Layer in XG-PON, 2015 38th Interna-tional Conference on Telecommunications and Signal Processing (TSP),no. 1, 2015.

[2] International Telecommunication Union. G.984.2: Gigabit-capable Pas-sive Optical Networks (G-PON): Physical Media Dependent (PMD) layerspecification. 2003. 2015-08-21.

[3] Yuanqiu Luo, Frank Effenberger, and Bo Gao. Transmission convergencelayer framing in XG-PON1, 2009 IEEE Sarnoff Symposium, no. 1, pp.1-5, 2009.

[4] Lukas Malina, Petr Munster, Jan Hajny, and Tomas Horvath. TowardsSecure Gigabit Passive Optical Networks, In Proceedings of SECRYPT2015, no. 1, 2015.

[5] Eduardo Tommy Lopez, Victor Polo, J. A. Lazaro, and Josep Prat. Layer 2redesign for Metro-Access next generation PON, 2014 16th InternationalConference on Transparent Optical Networks (ICTON), no. 1, pp. 1-4,2014.

[6] Qingpei Cui, Tong Ye, Tony T. Lee, Wei Guo, and Weisheng Hu. Stabilityand Delay Analysis of EPON Registration Protocol, IEEE Transactionson Communications, vol. 62, issue 7, pp. 2478-2493, 2014.

[7] Bonilla, Felipe Rudge Barbosa, and Moschim. Techno-economical com-parison between GPON and EPON networks, Innovations for DigitalInclusions, 2009. K-IDI 2009. ITU-T Kaleidoscope:, no. 1, pp. 1-5, 2009.

[8] Frank Aurzada, Michael Scheutzow, Martin Reisslein, Navid Ghazisaidi,and Martin Maier. Capacity and Delay Analysis of Next-GenerationPassive Optical Networks (NG-PONs), IEEE Transactions on Commu-nications, vol. 59, issue 5, pp. 1378-1388, 2011.

[9] Sami Lallukka, and Pertti Raatikainen. Link utilization and comparison ofEPON and GPON access network cost, GLOBECOM ’05. IEEE GlobalTelecommunications Conference, 2005, no. 1, 5 pp.-, 2005.

[10] International Telecommunication Union. G.984.3 : Gigabit-capable pas-sive optical networks (G-PON): Transmission convergence layer specifi-cation. 2014. 2015-08-23.

Tomas Horvath (MSc) was born in Havirov, CzechRepublic on March 7, 1989. He received his M.Sc.degrees in Telecommunications from the Brno Uni-versity of Technology, Brno, in 2013. His researchinterests include passive optical networks (xPON),optoelectronics, and BitTorrent protocol. Currently,he has been actually post graduate student at BrnoUniversity of Technology, Department of Telecom-munications and his topic of dissertation thesis isOptimization services in FTTx optical access net-works.

Petr Munster (MSc, PhD.) was born in 1984,in Zln (Czech Republic). He received his PhD atthe Brno University of Technology, Department ofTelecommunications in 2014 on the thesis entitledParameters of the FTTx networks. His current re-search themes focus on fiber-optic sensors, espe-cially distributed fiber-optic sensors, and also onfiber-optic telecommunications. He has about 50scientific publications in journals and conferencesin last 5 years.

Michal Jurcik (MSc) was born in Zlin on 29 ofMarch 1988. He is a Ph.D. student on the Facultyof Electrical Engineering and Communication BrnoUniversity of Technology on the Department ofphysics which started in 2014. In parallel he isworking as software test engineer for HoneywellInternational. He is also a co-investigator in projectCharacterization of materials and advanced coatingsin CEITEC. His dissertation is focused on studyof cold field emission cathodes and its properties.Due to his dissertation he cooperates with Delong

Instruments on electron microscopy. Currently he is working on prototype forcathode etching to improve the quality of etched tips and also programmingsoftware for it. He has experiences with programming languages such as C#,C++, C, VB, JAVA and Matlab. Biography text here.

Miloslav Filka (prof.) was born in 1946 in Brno,Czech Republic. Since 2010 he is a professor at theDepartment of Telecommunications at Brno Univer-sity of Technology. Hi is a leader of the opticalgroup OptoLab and also head of the Laboratoryof transmission media and optical networks. He isa member of a several institutes (e.g. Institute ofElectrical & Electronics Engineeres) and is alsocommittee of many conferences (International Con-ference Telecommunications and Signal Processing,International Conference New Information and Mul-

timedia Technologies). His current research themes focus on fiber-optictelecommunications, especially FTTx technologies. Biography text here.


novel algorithm in activation process of gpon networks

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