Bits
'n' pieces of the Networked world
Grid,
P2P and Distributed Computing
It
was quite sometime since I'd interacted with my friend
and former colleague Rajkumar Buyya. He is currently
in Australia, doing research at the Monash University.
He called me during a visit to the United States,
and updated me on his research.
His
personal website and his resume stunned me, and the
sheer variety and volume of the papers that he had
published during the couple of years that we had lost
contact simply amazed me.
His latest research pursuit is in the areas of Grid
computing, which focuses on what they believe are
fuelling areas of High Performance Computing (HPC)
by utilizing a global network of computational devices,
software and other instruments. His efforts in this
direction also grabbed my interest. The biggest motivation
for researchers of Grid computing is to address the
drivers for HPC, which are notably areas like life
sciences, digital imaging, CAD/CAM, e-commerce, aerospace
and military applications. The Grid concept envisages
the utilization of the distributed computing resources,
to fulfill the needs of the larger community, by a
global collaboration effort. The "Grid"
in essence is therefore envisioned as an infrastructure
that tightly integrates computations devices, software
(perhaps in an ASP model) catalogued databases, specialized
instruments, displays and people from widespread locations,
and under different management authorities.
What
is the kind of resources required to build a global
collaborative mechanism? Programming tools, software
that could translate requirements of an end application
into the requirements of computers, network and storage,
stringent security mechanisms, and end-nodes that
can integrate tightly with heterogeneous, multi-speed,
multi-protocol networks to start with. (See Figure
1.0)
There
are major challenges in the actual application areas,
concerning security (authentication, authorization)
etc., resource allocation, scheduling, access of remote
data sets or even collaboration on results that need
to be addressed. I have not also seen a comprehensive
report on how the bandwidth utilization and allocation
takes place when disparate, distributed resources
are being utilized, and this is something I'd like
to look up in greater detail.
Research
initiatives and test beds
However, there are dedicated teams working on these
projects. Practical initiatives are being made in
this
direction. Perhaps one that has made headway is the
Globus effort (http://www.globus.org), a joint initiative
between the Argonne National lab, NASA, American national
labs, and numerous universities. Essentially, the
focus of Globus is on a large-scale computational
grid, but side derivatives of this project are equally
interesting. A key deliverable achieved by effort
so far is the 'Globus toolkit' - a set of software
tools that makes it easier to build computations grids,
and power applications that run on them.
Validation
of these efforts requires test beds. The National
Partnership for Advanced Computational Infrastructure
(NPACI) and the National Computa-tional Science alliance
have built large networked grids deploying the Globus
software toolkit. A good source of information on
Grid computing research efforts, and pointers to resources
is available at http://www.gridcomputing.com.
Industry
efforts
More interestingly, work on these areas has already
moved from research labs, and test beds to commercialization.
Grid computing, distributed computing, and P2P (peer-to-peer)
computing - all sister areas, so to say-- form a triad
of hot areas that are being focused on. The year 2001
is looked on as the year where distributed and P2P
computing will come on its own. At least 15 companies
focusing on distributed and P2P computing were funded
in the last few months. Some call it "Internet
computing". Others have catchy names of their
own.
San
Diego based Entropia (http://www.entropia.com) has
developed Entropia 2000, a free software that activates
and recycles the resources (CPU, Memory etc.) to quietly
harness all the individual idle resources. (See Figure
2.0) Entropia has been in existence since 1997. However,
there are upstarts who are jumping into the fray with
gay abandon. Among these, most are companies looking
at the software aspect, and not necessarily the Internetworking
or bandwidth which is what I am concerned about. The
general assumption is that the Internet is going to
suffice. Recent entrants include Nextpage (www.nextpage.com),
Distributed Science (www.distributedscience.com),
Static Online (www.staticonline.com), and United Devices
(www.uniteddevices.com). All these companies are leading
efforts and contributing to the P2P effort. There
are others in the stealth mode - Centrata (www.centrata.com)
and Uprizer (www.uprizer.com) - who are yet to formally
announce their products and business models, but are
already drawing market attention. The prime motive
is money, but a lot of big names and talent have been
roped in into these companies from R&D institutions
and Universities.
You
could also volunteer to be a part of this global distributed
computing network, either on a payment or non-profit
basis. Process Tree (www.processtree.com) accepts
applications from large organizations, as well as
from individuals. Popular Power (www.popularpower.com)
also follows a similar model to Process Tree, and
offers to buy computing power. One other company that
I must mention, and about which I will write sometime
in detail later is Ejasent (www.ejasent.com), a company
that has good management, investors and is aiming
to gain a foothold in critical areas of Internet infrastructure,
availability and performance.
Clearly
both the industry, and the R&D community are sensing
an opportunity here. Microsoft is endorsing P2P computing
in a big way, Service companies like Viant (www.viant.com)
are doing it, and so are vendor companies like Sun
Microsystems. The latter is also contributing to Grid
initiatives through its Grid engine software, and
its 'Net Effect strategy'. Sun claims that its Grid
engine software can effectively harness the resources
on a network, and increase the efficiency by as much
as 5 to 10 times the usable power of a network. It
also claims to increase utilization levels to almost
98 per cent (http://www.sun.com/gridware). I am not
too clear about the overheads involved at this stage,
but as long as the efficiency claims are fulfilled,
that is perhaps my prime consideration. Still, I would
expect a large-scale deployment to involve considerable
polling, to find out which resources are free, a scheduling
mechanism that schedules and prioritizes jobs and
an integration mechanism that functions in a non-proprietary
environment. All these cause overheads on network
utilization, and can cause performance bottlenecks.
It will be interesting to see how these are resolved
on a global scale.
It
is ironic that Napster (www.napster.com), that helped
create a new revolution to share MP3 files, and perhaps
contributed to P2P computing getting a boost, has
been sidelined. Improving upon this kind of technology
are companies like Mojo Nation (www.mojonation.net)
that are evolving innovative ways of distributing
content.
Ultimately
in the next one year or so, when these companies stabilize
their solutions to address issues of distributed computing
and content delivery mechanisms, they would need to
synergize with players from the broadband communications
space. With broadband becoming such a hot area, and
broadband content delivery assuming considerable significance,
this space is going to generate heat. Major broadband
players are going in for the ability to offer enhanced
personalization at the edges, and the end-user experience
is going to be key. I strongly suspect that the two
areas could converge sometime soon.
Broadband content delivery
The last two years have seen content delivery become
a major force to reckon with. With the decline in
e-businesses and dot.coms, this segment had been issued
with a premature death warrant, but the industry suddenly
seems to have come alive, and raring to go. Sometime
back, I had dealt with content delivery (CD) network
mechanisms in this column. I had also profiled some
players in the CD market. Since then, there has been
change in the way these companies are being perceived,
not because they have lost the edge on technology,
but because they have lost market momentum. While
the market capitalization of companies like Akamai
or Inktomi is nothing to write home about, with the
steep falls in their net worth, the CDN community
as a whole is very much active, with broadband equipment
vendors, and internetworking giants like Nortel (www.nortelnetworks.com)
and Cisco (http://www.cisco.com) emerging as strong
players in this field.
The
ability to deliver personalized content to the end-user,
and provide premium services to generate revenue,
however nominal, has been touted as the way to go,
especially after all the free ISPs, and others providing
free content, have been forced to close down shop,
or reduce the scale of their offerings one after the
other. The potential to generate revenue and then
sustain it, is perhaps the only barometer of performance
for a company, and rightly so.
But
let me not digress. With the growth in the cable modem
market, and end-users moving towards interactive television
experiences, and personalized portal experiences,
it is only right that broadband content delivery networks
are assuming significance. The ability to personalize
does not just mean customizing the look and feel,
but also the means to provide a finer degree of access
control (for the end-user and the ISP POPs), freedom
to modify and access content with the right authority,
and then to make all this accountable.
Consider
the old Internet landscape (old in Internet time is
an year ago) - See Figure 3. We had subscribers connecting
to the Internet through ISP POPs over low-speed dial-up
links, and accessing content hosts. There were numerous
performance bottlenecks, right from the dial-up links
which were of poor quality (more so in India), to
the Internet backbone (a best-effort mechanism), to
the inability of content-hosts to regulate and control
the way in which content was delivered. Being transparent
to the subscriber, his loyalty towards a particular
ISP was motivated completely by his user experience.
ISPs and portals took a big hit for sometime in their
efforts to attract subscribers to their fold, and
the cost of acquiring a new subscriber became quite
expensive. ISPs, which began offering advertisement-powered
free subscription as the ultimate incentive, have,
as I mentioned been struggling to remain operational,
and subscriber loyalty has been increasingly hard
to maintain. The bluelights (www.bluelight.com) and
NetZeros (www.netzero.com) of the world have been
hard put. So is the case with the free PC, and free
DSL providers. This has also adversely affected the
large-scale hosting solution and service providers
like Exodus (www.exodus.net) and Globix (www.globix.com),
amongst others. In effect, it has been a chain reaction.
Now
things are changing. The effort is no longer towards
luring subscribers with the free carrot, but to offer
service, and make the discerning subscriber pay for
premium utilities and services. It is somewhat akin
to what the cable TV medium has been following in
the United States, with basic, medium, premium and
personalized plans (the last is in the offing).
While
it may take sometime for the web, and television mediums
to merge cohesively, there are indications that we
are going there. A similar approach on the Web needs
to evolve and stabilize before the two can converge.
How does one unify the end users, ISPs, hosting services,
and content providers to deliver a consistent experience
that benefits all? As a beginning, we see companies
like Akamai (www.akamai.com), Sandpiper (www.sandpiper)
and Digital Island (www.digitalisland.com) taking
initiatives in moving the content closer to the user,
from the content hosts to perhaps the localized ISPs,
and their own POPs. This was essentially narrowband
content, and the prime motive was to accelerate delivery
of content, and enhance caching response times.
Broadband
content delivery mechanisms are trying to build upon
this. A range of features is being added. This includes
providing a granular degree of security, to controlled
advertising, to quality of service, and pay-per-use
mechanisms that could be dynamically activated.
How
does one go about setting this model in place? What
are the pre-requisites? For starters, subscribers
need access to broadband connections, either through
cable modems, fixed wireless access, DSL or whatever
the mode might be. There is work going on in standardizing
network logins, service advertisements, and service
selection via a browser. Depending on the type of
content, there could be mechanisms to deliver premium
content over tunnels, to ensure a Quality of Service
(QoS) look and feel. As far as the ISPs are concerned,
or even the content hosts, work needs to be done on
standardizing network logins (into the content site),
and both the service advertisements and semantics
need to be standardized to offer branded content services
to the subscriber through a web-page. The ability
to monitor and bill subscribers based on service level
agreements (SLAs), and pre-defined policies is very
vital.
The
result is that broadband content is delivered to the
end subscribers, directly via their individual broadband
connections, and the ISP POP becomes a medium for
content mediation. Broadband service nodes play a
key role in these applications, and it is essential
that both the service providers (viz. content, network
and infrastructure services, and the vendors) viz.
(Network, content caching and billing) join hands
to provide the best possible end-user experience to
the subscriber. I am happy to say that this is already
happening.
Next
month, there is a convergence of players in the content
delivery space at New York (http://events.stardust.com/
cdn/) and this should raise some dust. Industry leaders
are participating, and hopefully, unlike the last
couple of years, we should have technology, and not
hype as the catalyst. There is an interesting, and
extremely well written white paper on the website,
which I'd recommend to enthusiasts of content delivery
mechanisms. Look it up at http://events.stardust.com/cdn/documents/CDN_whitepaper.PDF
Till next time, Happy Networking!! NM
N. Shashi Kiran works for Nortel Networks
at Santa Clara, as a Product Manager. The views expressed
are his own. He can be reached at shashikiran_n@hotmail.com