In the final lecture of the Cloud Computing course, the instructor wraps up by summarizing the key topics covered throughout the course and highlighting future research directions in the field. The course provided an overview of cloud computing, covering its characteristics, advantages, and service models such as IaaS, PaaS, and SaaS. Important issues such as service level agreements, cloud economics, resource management, and cloud security were also discussed. The transcript delves into potential research avenues like cloud infrastructure, data management, and emerging technologies such as fog computing and IoT. The course encourages further exploration and study in these diverse and evolving areas of cloud computing.
Highlights
The instructor provides a comprehensive overview of cloud computing and its service models. โ๏ธ
Importance of service level agreements and cloud economics is emphasized. ๐
Future research directions are explored, including infrastructure advancements and data security. ๐
Discussions cover emerging technologies like fog computing and their impact on cloud services. ๐
Cloud computing's dynamic nature makes continuous learning and adaptation crucial. ๐
Key Takeaways
Cloud computing offers vast opportunities for innovation in various service models like IaaS, PaaS, and SaaS. ๐ฅ๏ธ
Data management and security remain crucial challenges, offering rich research possibilities. ๐
Emerging technologies such as fog computing and IoT are transforming the landscape, suggesting exciting research directions. ๐ค
Understanding cloud economics is essential to optimize both cost and performance benefits. ๐ธ
The field is ever-evolving, and staying updated with the latest research trends is crucial. ๐
Overview
Welcome to the final curtain call of the Cloud Computing course! Our intrepid instructor takes us on a whirlwind recap of the journey we've been on, highlighting the core lessons and contemplating the vast universe of future research possibilities within the ever-expanding cloud. The course has been our guide through the intricate maze of service modelsโthink SaaS, PaaS, and IaaSโand crucial concepts such as resource management and the economic forces at play.
During this knowledge-packed session, the conversation steers toward monumental research opportunities in the cloud computing arena. From infrastructure enhancements to solving the enigma of data security, there's no shortage of intriguing avenues to explore. Furthermore, the integration of emerging technologies like fog computing, IoT, and even sensor networks hints at a thrilling frontier for those eager to push the boundaries.
Cloud computing isn't static, but rather a dynamic and rapidly shifting entity, likened to our ever-changing skies. The course encourages us to maintain our curiosity and enthusiasm for learning, inspiring us to dive deeper into these complex, yet fascinating technologies. Here's to the endless sky of opportunities that await those who choose to explore this exciting domain!
Chapters
00:00 - 01:00: Introduction and Course Overview This chapter serves as an introduction and overview of the cloud computing course. The instructor greets the audience and indicates that this is the final lecture. The focus of the discussion will be on summarizing and reflecting on the content covered throughout the course.
01:00 - 04:00: Cloud Computing Fundamentals The chapter titled 'Cloud Computing Fundamentals' provides an overview of potential openings and research directions in the field of cloud computing. It also emphasizes topics that can be explored for deeper study for those interested in this domain.
04:00 - 05:00: Evolution and Utility of Cloud Computing The chapter titled 'Evolution and Utility of Cloud Computing' provides an overview of the vast and complex domain of cloud computing.
05:00 - 08:00: Cloud Architecture and Service Models The chapter introduces cloud computing with a basic NIST definition. It emphasizes the concept of 'everything as a service' and discusses the properties, characteristics, advantages, and disadvantages of cloud services.
08:00 - 12:00: Service Management and SLAs The chapter 'Service Management and SLAs' discusses the evolution of computing technologies. It emphasizes that new technologies do not appear suddenly; rather, there is a progressive development. The text mentions phases such as cluster computing, grid computing, and distributed computing that have led to the current advancements in computing.
12:00 - 16:00: Cloudonomics and Economic Considerations This chapter discusses the concept of cloud computing as a utility service. It highlights its characteristics, such as the pay-as-you-go model, scalability, and the idea of it being a metered service similar to utilities like electricity and water.
16:00 - 20:00: Resource Management in Cloud The chapter discusses resource management in cloud computing, emphasizing the benefits of scalability and the lack of infrastructure maintenance required on the user's end. It explains that users only need to connect to a service and begin computing. The basic architecture of cloud computing is covered, highlighting common service models such as Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS).
20:00 - 23:00: Data Management in Cloud The chapter titled 'Data Management in Cloud' discusses various aspects of cloud services, focusing on service-oriented architecture and foundational technologies. It mentions the potential for manifesting different types of services within this framework, even if not explicitly covered in the accompanying slides.
23:00 - 29:00: Cloud Security The chapter 'Cloud Security' discusses the foundations of service-oriented architecture (SOA) and its key role in cloud computing. It highlights the importance of interoperable services and XML technology that facilitate the implementation of SOA. This approach serves as a crucial pillar in the architecture of cloud computing, enabling diverse services to integrate and function collaboratively.
29:00 - 32:00: Open Source and Commercial Cloud Platforms Service management aspects are discussed, focusing on service level agreements (SLAs) in cloud services. These SLAs are crucial as they define the expected level of service between interacting heterogeneous services. The chapter emphasizes the importance of strong SLAs for successful integration in a cloud framework, indicating that without them, maintaining a reliable service framework becomes challenging.
32:00 - 36:30: Advancements in Cloud Technologies The chapter delves into the progression and improvements in cloud technologies, emphasizing the importance of maintaining a high quality of service. It highlights the expectation of reliability by organizations and individuals when utilizing cloud services, such as using cloud infrastructure to support institutional labs.
36:30 - 45:00: Research Areas in Cloud Computing This chapter discusses the expectations and requirements of outsourcing systems to the cloud. It focuses on the reliability and uptime guarantees that cloud services must provide, especially for mission-critical operations. These operations include sectors like banking, financial services, defense, and disaster management, where high availability is crucial. The chapter likely explores the standards and agreements, such as service level agreements (SLAs), that are necessary to ensure these systems function smoothly and efficiently in the cloud.
45:00 - 52:00: Conclusion The conclusion emphasizes the need for more robust healthcare systems, emphasizing high availability and reliability. It discusses the importance of strong Service Level Agreements (SLAs) to ensure that services agreed upon are delivered as promised. The chapter highlights that commercial cloud service providers generally offer SLA formats, but notes that there are differences observed in them.
Course Summary and Research Areas Transcription
00:00 - 00:30 hello so welcome to our final ah lecture on
cloud computing course ah so today what we are trying to discuss is we will be discussing
is primarily looking at what we tried to cover
00:30 - 01:00 in this course and also we will give you an
ah quick ah overview or of that what are the possible openings ah or what are the possible
research directions ah which you can explore ah or you can study more if you are interested
in this particular ah particular field right so so in this ah ah particular course ah we
try to discuss on ah some of the ah ah topic
01:00 - 01:30 or some of the areas of cloud computing as
we all understand there is a vast area vast area of things rather ah if you can see that
every topic itself is a ah course by itself ah so what we what ah my major effort was
to give you an overview and what are the possible ah ah challenges what are the different characteristics
of cloud or different ah properties of cloud
01:30 - 02:00 and what are the different aspects we tried
to look into and ah which service that technology involved into things so we tried we we started with basic introduction
with cloud computing ah with a basic ah nist definition and ah which ah what we emphasize
that it everything as a service so and ah then ah try to see that the basic property
characteristics rather advantageous and disadvantages
02:00 - 02:30 of such a such type of computing as ah we
discussed and try to reiterate that it is not suddenly a new ah technology which suddenly
drop from the sky so there is a evolution process we started there are there are ah
several effort towards this sort of ah activity like ah we have gone through phrases of cluster
computing grid computing ah distributed computing
02:30 - 03:00 and finally ah came up to this cloud computing the basic ah beauty or the basic ah characteristics
of this sort of computing as we have seen is that it is it is what we call a a form
of a utility computing like as as as a as a as a utility services like electricity or
water or anything you can basically pay as you go model right its a metered service scalable
a service ah you can scale to at infinite
03:00 - 03:30 scaling and the other thing is that it dont
have to maintain the infrastructure at your end so you need somewhere as to hook into
the thing and then ah start computing and ah also we have seen that if basic architecture
and try to look at the basic cloud computing stack there the popular service models like
a though it is a anything as a service we have seen primarily infrastructure as a service
ah platform as a service and software as a
03:30 - 04:00 service the primarily these three there are
different other type of service anything which can be manifested it as a service ah service
mode is a is possible in this sort of ah framework right ah so rather ah though it is not ah mentioned
explicitly in the slide what we have seen that the the basically the foundation technologies
like service oriented ah architecture web
04:00 - 04:30 services and ah xml ah technology so we have
gone through those things also right we have taken a overview of those things also which
helped us into interoperate and make these service oriented architecture possible so
this basic service oriented architecture or service oriented approach ah is the ah what
we can say foundation of or another pillar of this ah cloud computing architecture
04:30 - 05:00 then ah also we have seen ah some aspects
of service management primarily with respect to service level agreements right slas which
plays a important role because as a loosely couple ah heterogeneous services are talking
to each other these ah service level agreements plays a important role in realizing this sort
of a this sort of ah um framework right unless unless we have a strong service level agreement
or then otherwise it is very difficult to
05:00 - 05:30 have a to maintain a quality of appropriate
quality of services right so a whenever whenever someone is taking ah
is leveraging cloud then it is a the a organization or individual is expecting some sort of a
reliability from the cloud right like if i am if i am taking ah if on behalf of our institute
for running a lab we are taking a taking ah
05:30 - 06:00 um outsourcing our system to the cloud then
what i am expecting that there will be a faithful ah uptime right it is a of a particular level
says i ninety nine percent ninety nine point percent and so and so forth which will be
supported by the cloud if it is more missing critical operations
like bank or ah similar financial or even ah some of the ah say defense or disasters
management or those type of operations then
06:00 - 06:30 we what we require is more ah or health care
systems then why what we require is more high level availability and reliability on the
things so how to bound that that whether what i what i am what i am paying for or what i
i have agreed upon whether i get that services so for we require a strong slas and that every
clouds service provider specially these commercial provider ah have provide a sla format though
there are what we have seen there are differences
06:30 - 07:00 between the formats and type of things but
its a plays a important role in our in having cloud services similarly we talked cloudonomics is cloud
is always a good thing right so what is the economy behind the cloud when we should go
for cloud when we should not ah or stick to our own ah own in house ah computing facility
whether it is infrastructure platform and
07:00 - 07:30 so and so forth so though so if there is a
particular economy which comes into play and we have seen that ah we need to look look
at that those economic aspects whenever we are going to ah going to basically outsource
some of of my business or part of my business to cloud right so cloud cloudonomics ah specifically what
economy in cloud what we have looked into there can be other aspects even cloud may
be economically ah beneficially but my ah
07:30 - 08:00 other constraint like may be security constraint
my privacy constraint may not allow me to push all the data to the cloud right like
iit kharagpur may decide that i i can run the labs on cloud but i i may not put my student
data employee data on cloud because finally it is on the third part domain so thats a
thats a that type of thing also come into play so it is not only whether it is economical
in terms of ah money it is also to be that
08:00 - 08:30 what should be the organization policy individual
policy how much i should push on the cloud and so and so forth so never the less cloud economics plays the
important role to decide when to go for cloud and when ah when to take it on ah on in a
house type of things then we have discussed ah i i believe one or two lectures on cloud
resource management in cloud right so its a its a very important issue right resources
resource management in the cloud is is play
08:30 - 09:00 a both from the providers and particularly
also sometimes it is from the consumer end but never the less for the resource management
ah the resources ah management in from the provider sense plays a vital role right like
i have ah though i say that i have infinite resources as my backend right but it is ah
but it is tangible right i cannot say that it is not ah there is a limitation of the
things not only that resource also takes lots
09:00 - 09:30 of other energy right so it comes with back to back that some sort
of a consumption and so and so forth like even i have i can give a number of ah ah if
there is no constant the resources is to maintain the resources i need to ah have lot of ah
energy at the things so appropriate resource management so that ah overall it is beneficial
in terms of ah in terms of that the say profitability
09:30 - 10:00 of the service provider it is it is not a
adverse to our environment or ah consuming more energy so this appropriate resource management
plays an important role not only that you if you if you see the literature or recent
ah works in several that peer reviewed journals or top level conferences this resource management
is always a plays a important part of that
10:00 - 10:30 so this is this is a very vital aspects ah
in case of a in case of a ah cloud management or cloud computing then we have seen ah data
management in cloud its a very ah tricky issue finally whenever the data is in cloud it is
your data ah or our data is on third party right so i dont know that what is happening
to the data though there are there are definitely
10:30 - 11:00 security issues apart from the security issues
there are several issues like how whether ah what what will happen that data if it is
lost or something how what about the scalability of the data if if the quickly i can grow on
the data what should be accessibility of the data is there in the cloud it is not cloud
storage is not lost however ah the i i dont have appropriate bandwidth to access the data so there are several issues ah in in case
of data management we have seen some of the
11:00 - 11:30 things like ah like google file system ah
hdfs hadoop file systems and what we have seen that that how the application policies
works and ah how this huge data thing ah are maintained not only that it also while talking
to this ah data management the one thing in variably come is that big data management
how this big data can be managed in the in
11:30 - 12:00 in cloud right so we have seen that ah other
technologies like a map reduce ah sort of technologies where we can paralyze this operations
and ah do and can have a better efficiency or of ah processing a particular work in the
cloud so this is very again they are very interesting
area to work on or study more and type of things then of course one major concern in
cloud is cloud security we have also tried
12:00 - 12:30 to looked into some aspect of cloud securities
tried to show some of the recent ah train in the things we have ah discussed these in
three four ah lectures so there are several aspects of the things like one is identity
and access management ah access control mechanism whether it should be role base access control
or ah use of risk base of access control and type of things there are different ah aspects
like trust reputation risks competence and
12:30 - 13:00 type of things right so how to handle them ah how to ah take a
call considering all the things how to further for example how to how do i calculate trust
of a of a particular provider or even how the provider try to ah profile his own customer
right so so there are ah major issues in their definitely authentication is another major
aspect how to authenticate ah ah how the authentication
13:00 - 13:30 protocol will run on the things and ah as
as as we understand that ah security ah in ah say data security in cloud is also a major
aspects like ah it may not be always possible to encrypt the data even if you encrypt the
data how this key management will work on the things right your data is in third party
ah aspects and then how this overall key management
13:30 - 14:00 aspects ah will work in this type of ah there so this is also a very strong field because
as more organization more individuals ah are ah going towards ah this sort of infrastructure
ah pushing their data their applications services on the ah cloud so how this security is maintained
or how this ah security data security can
14:00 - 14:30 be guaranteed becomes a major resource as
we as we have seen in our country also now several major ah competitive exams are are
ah being ah conducted over clouding infrastructure now those securities like how this ah question
paper will be encrypted how the answers will be encrypted and securely transmitted and
ah if it is stored in the third party whether there is a there there is a possibility of
any leakage of ah any data so there that needs
14:30 - 15:00 ah lot of ah lot of study and what we have
seen that that is that is a that is a major ah one of the research area also and one of
the most ah what we say ah um talked about ah concerned about our challenges in cloud
15:00 - 15:30 also we tried to show you some of the open
source as commercial cloud right though it is not ah possible to cover everything but
we have tried ah with open stack ah and also we have shown ah how in our iit kharagpur
we have ah implemented with help of students a a a ah um experimental cloud called megomalla
and how it is serving to a research community though in a small scale but its a its a operational
thing though it is experimental so its its
15:30 - 16:00 based on totally open source things on open
stack and there are several open commercial cloud like ah amazon azure google cloud platform
ibm bluemix and so and so forth we have tried to show some ah example cases
ah so that it ah it will gives you a ah opportunity to quickly know about the things and work
on this type of have a feel on the things
16:00 - 16:30 the basic basic ah basic idea is to have a
feel of the things and ah finally we ah last few lectures we discussed about some of the
related technologies ah and ah um some of the what we say companion technologies to
cloud computing like one is fog computing so what we what we are seeing that the that
devices ah in recent ah days or last one decade
16:30 - 17:00 are becoming more resource full so that there
is some sort of a it is not only acquisition of information and forwarding the information
we can basically have the opportunity to process the informations so if that is the situation why not do some
ah operation at much lower level and then ah we can provide the result to the things
this will not only ah help us in reducing ah the ah bandwidth requirement ah to um connect
to the cloud but also some of the local decisions
17:00 - 17:30 which which could have been done at a local
thing ah we can ah we can do we can ah basically ah achieve that this will help us in having
more quote unquote some sort of a real time application to run more faith fully right so this this some of the aspects we have tried
to see in then we have talked about sensor network sensor cloud right ah that as we have
sensors are omnipresent these days so why
17:30 - 18:00 not if there is a formation of a sensor cloud
we talked about container ah technology ah like ah specifically on the docker technology
that how it can be um used for in the context of cloud computing how this cloud and this
container technologies there and of course this green cloud or ah like that it it comes
to that energy management resource management of the cloud can be there so some of the things what we have tried and
a what we have discussed may be ah discussed
18:00 - 18:30 which which may ah help you in finding your
ah future research directions now what what ah what we tried to again i let me repeat
what i tried to do in this course is to basically open up this different avenues right so it
is within ah some ah of of this sort ah this sort time period it may not be possible to
discuss everything in details but definitely
18:30 - 19:00 we we can we see that that that lot of opportunities
are there now let me with ah given these backgrounds
so let just discuss about some of the research areas ah in cloud you may find in the internet
i do have found some of um most of the things in the internet and ah like ah so just want
to discuss ah some of these aspects of the things so one ah definitely ah if we look
at our ah the course and things one definitely
19:00 - 19:30 this infrastructure and services plays a important
role like a cloud computing architecture storage data architecture distributed and cloud networking
infrastructure technologies these part a important role and it is it is ah sort of a ah with
with the ah hardware and other related technologies upcoming technologies coming in to play so it is never a saturation field right it
is always there is a scope of ah contributing
19:30 - 20:00 ah into the things and making the make making
ah the infrastructure more intelligent and meaning full apart from there there are services
like there are basic services like iaas paas saas which which are also evolving every day
or ah in a regular fashion there are ah other type of services which are becoming very popular
one is storage as a service ah again very
20:00 - 20:30 tricky and critically issue critical service
which which everybody needs from the individual to organizations every to federal agencies
everybody needs it and ah there are other services like network as a service like i
want to setup a network or based under that rather i can have different network i want
to have different network ah um configuration at different part of the ah day or different
different time period based on my requirement
20:30 - 21:00 or my clients requirement i want to set up
a things so what i require instead of giving a a a
physical network i want to have a network as a service type of things there can be other
type of services like a information as a service so information being ah accessed as a service
even people talked about concept like science as a service and type of things right so there
are there are lot of (Refer Time:21:00) opportunity
21:00 - 21:30 both research study and type of higher ah
studies in the area of cloud infrastructure and services so this is one of the important
core field of course the management operation and monitoring is another ah interesting area
or important area so cloud composition service orchestration between services cloud federation
bridging busting cloud busting and those type of thing cloud migration hybrid cloud integration
ah like green and energy management of cloud
21:30 - 22:00 computing i kept it in bold because that is
that stand out that this is this is this is not only a ah ah a research field it is also
a a major challenge and requirement to make this cloud computing a success right configuration and capacity management how
to how do i configure reconfigure my infrastructure as a service provider and how to estimate
my capacity type of things cloud work load
22:00 - 22:30 profiling and deployment control again another
important aspects and if you see these are the things which are not exact these are not
in isolation there are interconnected right ah then cloud metering monitoring and auditing
of the services service management so there are different aspects of ah cloud management
operation and monitoring which which plays a important role and as we already discussed that cloud ah
security is is ah is an important is ah is
22:30 - 23:00 ah need to be appropriately addressed so that
people ah or organizations get confident to store their data in to this cloud there are
not only technological issues there are several legal issues right if there is a data leakage
how this this need to be handled in the law law of ah things if i need to be handed in
the federal law then the physically the data should be stored may be has to be stored in
the in the ah physical boundary with in the
23:00 - 23:30 physical boundary of a particular country
or particular state right so there are several issues which need to
be addressed so privacy data privacy access control ah issues identity management there
are issues of side channel attacks which are becoming popular like the it is it may not
be the directly looking at the activities but looking at the some other ah activities
or basically understanding the basic operational
23:30 - 24:00 things i can i can basically adjust some of
the things we have discussed during the security while we are discussing about the cloud security
in our ah previous lecture that what we have seen that ah when we ah there is form a in
a paper which is which we says that by looking by understanding the basic philosophy of allotment
and type of things i am able to guess somewhat
24:00 - 24:30 that ah say ah the ip address block and type
of things in in a particular ah of a of another client if i can if somebody can do that then
there is a possibility of the security bridge right so these are different security aspects especially
if it is a if it is a ah mission critical things then the organization or individual
ones that security should be there so so there
24:30 - 25:00 is a whether there is a question that whether
security as a service can evolve right whether we can provide security as a service ah in
the in this context ah another ah another interesting and ah of course important aspect
is that performance scalability and reliability of cloud computing right so performance and of cloud cloud systems
and applications is a another major issue
25:00 - 25:30 like how to measure performance how to ah
um basically ah maintain that performance at particular level of performance and with
with with proper resource management cloud availability and reliability ah is that like
micro service based architecture so a service may that different micro services so whether
my particular underlining architecture can
25:30 - 26:00 support this type of micro services so i whether
i can designed a micro services based architecture for handling ah for better performance scalability
and reliability of course system software and hardware plays
a important role ah like virtualization technologies ah whether the better virtualization technologies
service compositions cloud provisioning ah
26:00 - 26:30 orchestration and hardware architecture support
for the cloud computing so instead of taking any hardware whether the whether the hardware
itself has ah is supported to this implement this cloud so this is also a important aspect
it needs to it need to for in order to work on that you you need to know more about the
internal ah working or internal ah um more implementation details of architecture and
development of architecture and type of things
26:30 - 27:00 data analytics in cloud data analytics is
the buzz what these days we with huge volume of data and every aspects of the things whether
it is business banking ah metrological data or educational data where everywhere this
ah analytics is there whether and as cloud ah what we have seen its a its a infrastructure
which can hold ah huge volume of ah data may
27:00 - 27:30 be and also application running on the data
right so yeah and not only that it tries to give ah ensure interoperability between the
between the different data sources so this data analytics in cloud is is is one
of the ah one of the very hot topic of ah research so there are different analytics
application developing analytic as a scientific computing and data management so it is not
that data management and computing a separate
27:30 - 28:00 but whether i can i can my management goes
in more ah hand to hand with the computing aspect big data management analytics storage
data and analytics clouds so these are these are some of the things which are coming up
in a big way and there is a lot of opportunity ah to work on this areas ah and another aspect
like cloud computing the service management ah in cloud is a they are like services discovery
and recommendation services composition services
28:00 - 28:30 quality of ah qos management right the qos
management of the services right so what we are trying to look at so security
and privacy services security and privacy of these services so different services are
there what about the security or privacies of these services there is a semantic services
right so that is a that is whenever what ah like a different domain has different type
of dynamics into the things right different
28:30 - 29:00 type of semantics into the if i try to look
at that whether predictions and type of things so there is a underlying semantics into the
things how to incorporate that semantics and ah come up with semantic services so and service
oriented software engineering aspects where how to put it on the cloud so these are the some of this other aspects
which are which are ah which are becoming popular and ah finally they are several technologies
ah which are coming up and how cloud and those
29:00 - 29:30 technologies come into play we have already
discussed ah these things like one is fog iot cloud is another aspect sensor iot clouds
sensor cloud ah ah things are there and this container technology as a we have looked into
docker technologies so how these technologies and cloud computing can go hand in hand to
provide better services
29:30 - 30:00 so these are some of the aspects which which
we try to look ah into ah while ah as a future scope or what we say that ah recent ah trend
in research so one one major ah one good place to find the that what are the different what
are the upcoming field or what are the present ah um direction of the research is looking
at ah top level channel general transaction
30:00 - 30:30 and looking that what sort of ah special issues
or sort of ah scope of things are there and also top level conferences say what they are
scope of the topics they are looking for those type of things are there so with these ah let me ah conclude this course
hope you have ah enjoyed ah these ah particular ah ah course and ah there and you could find
some interest in this particular ah aspect
30:30 - 31:00 of ah cloud computing so what i what i ah
believe or what i what i ah basically look forward to ah is that this will help you in
ah in further higher studies in this aspects ah and also those who are interested in research
in this field will find lot of opportunities
31:00 - 31:30 are there so there are ah some of the things which you
can look into that there are several cloud simulators are available it is it may not
be always possible to develop a infrastructure or or getting infrastructure or higher cloud
to experiment so there are ah simulators which we can ah which you can work on to see that
whether things are ah whether ah whatever you experiment on the or whatever you are
thinking can implement on the things so with
31:30 - 32:00 these ah let me conclude these ah course and
ah thank you ah very much to participate to for participating in this course thank you