From server huggers to cloud addicts to the optimized data center network - learn more about Juniper Networks' data center solutions here: http://juni.pr/SSlpP2c

1. 1
WHAT’S NEXT IN THE
PATH TO THE CLOUD?
From Server Huggers to Cloud Addicts to the
Optimized Data Center Network
From Server Huggers to Cloud Addicts
Once upon a time, IT needed to convince application owners
to virtualize their servers instead of hanging on to a dedicated
physical server. Now, many IT shops have won that battle, with
Virtual Machines (VMs) becoming the de facto standard, and
old “server hugger” application owners increasingly sold on the
benefits of server virtualization.
The End of Server Huggers: Key Benefits of Past Server Virtualization Projects1
None of the above
70%
70%
51%
49%
43%
4%
Energy savings OpEx
Easy maintenance
Business operational efficiency
Flexibility and speed of rolling out new services
Hardware savings CapEx
With the availability of new IT infrastructures
and cloud services that are faster than ever
before, a new set of expectations around
speed, agility, and time to market have been
established. Today’s “cloud addict” application
owners expect instant provisioning of compute,
storage, and network resources, and business
managers increasingly cringe at the possibility of
infrastructure constraints.
Figure 1: Survey results: Company benefits from past virtualization projects
1
Source: IDG CIO Virtualization Quickpoll, Sponsored by Juniper Networks, Nov 2011, Base: 138 qualified respondents

2. 2
Cloud Addicts dictate success attributes for future virtualization projects2
Energy savings OpEx
Hardware savings CapEx
Easy maintenance
Business operational
efficiency
Flexibility and speed of
rolling out new services
Significant increaseChange in importance: Slight increase No change
Slight decrease Significant decrease
Figure 2: Survey results: Anticipated impacts of future virtualization projects.
For infrastructure architects and managers, the
next phase of virtualization will require balancing
the workflow demands of cloud addicts, while
continuing to migrate legacy applications and
services onto a virtualized infrastructure that is
optimized for efficiency. As seen in Figure 2, while
business agility determines the success of future
virtualization projects, improving efficiency and
reducing maintenance burdens are also rising in
importance.
The Security and Management of Cloud Addicts
If left unchecked, cloud addicts (or even regular
IT staff) have been known to spin up virtual
machines with wild abandon causing VM
sprawl. Or perhaps they create VM with unique
configurations rife with security vulnerabilities
and compliance violations. Meanwhile, VM-to-
VM communications are able to bypass the long
trusted presence of the physical firewall located
multiple network stops away. Finally, as the
importance of the applications in a virtualized
environment rises, the old security models need
to be revisited to ensure that only infrastructure
resources are shared.
Key questions to ask:
• As more important applications are virtualized,
how will you evolve the security model to protect
business critical applications?
• Can IT staff or others create virtual machines with
inconsistent and/or vulnerable virtual machines?
• Can you secure VM-to-VM traffic without
constraining the number of virtual machines per
host or the performance of the applications?
The Cloud Addict Push Toward Shared Compute—Time to Optimize
After the first several rounds of server
consolidation, many VMs rarely move off or
require human intervention. In this mode of
operation, compute resources are used more
efficiently and flexibly, but cannot be used as a
shared and common pool of resources for other
applications that need them.
Even if the notion of a shared pool of compute
resources is too aggressive, the tendency for
application owners to overestimate the resources
used by an application can lead to significant
over provisioning, as the percentage of virtualized
workloads approaches 100%.
2
Source: IDG CIO Virtualization Quickpoll, Sponsored by Juniper Networks, Nov 2011, Base: 138 qualified respondents

3. 3
Key questions to ask:
• How quickly can VMs be moved in your data center?
• Can VMs be moved without threatening
performance or availability of all applications?
• Can you measure the resources used by
applications over time to determine the true
needs versus the estimated needs of the
application set?
• Do you need to build your infrastructure to handle
peak loads or average loads with the use of cloud
services for peaks?
Table 1: Summary of Data Center Changes and the Impact on the Network
Infrastructure Element Change (Old vs. New) Network Impact (Old vs. New)
IT infrastructure availability Old: Delivered by IT Old: Static connections inside and
between data centers
New: Globally resilient, obtained via
cloud service and/or delivered by IT
from multiple data centers
New: Dynamic connections inside and
between data centers
Application architectures Old: Client/server Old: Data center networks optimized for
client/server (north-south) traffic
New: Distributed components
combined into services
New: Data center networks optimized for
server-to-server and server-to-storage
(east-west) traffic
Compute Old: One physical server per app Old: Each application’s compute and
data stays physically in one place
New: One virtual machine per app on
shared physical compute
New: Virtual machines can move around
the data center based on demand
Storage Old: Physical storage dedicated to
a single application (direct attach)
or small number of applications
(storage area network)
Old: Separate and dedicated storage
networks with access governed by
cabling
New: Virtualized storage and master
data initiatives dictate common
pools of data available to all
applications
New: Data physically connected to every
app, with access governed by policy;
requires low latency, low jitter networks
to minimize the network distance
between processor and disk
Security and network services Old: The “castle with a drawbridge
model” that places a large appliance
dedicated to a particular service
between the router and the server
Old: Stack network appliances in a
conga line specific to particular network
segments
New: The “hotel model,” with
multiple layers of security;
applications housed in rooms with
different resources, (penthouse vs.
ballroom, etc.)
New: A pool of network and security
services available to all traffic flows
combined with firewall services built to
gain visibility and security for VM-to-
VM traffic without constraining app
performance or compute efficiencies.
As we have seen, location matters In a legacy network. Resources that need each other have to be
placed next to each other, and the physical location of a virtualized application resource inside a data
center can have a significant impact on application performance, security, and the agility of distributed
applications. Components of an application are also optimally placed in the same vicinity and ideally
behind a single switch. In the future, service-oriented architectures will require that all assets in the data
center have connectivity to all other assets.

4. 4
Figure 3:
Building a larger bubble
for optimal performance
Larger Bubbles Are Needed
When application assets are placed behind
a single switch, the communication between
application components is fast and more
importantly predictable and consistent (see the
left side of Figure 3). Sometimes this happens
by design; sometimes it is happenstance due
to project-based infrastructure build out. As
you can see in the right side of Figure 3, when
an application component (generally a VM) is
placed farther away from the other components,
latency increases along with unpredictability of
the traffic as other applications come barreling
through the network. Unfortunately, physical
distance is not always the best indicator of
network distance.
Bubble
Optimal performance
Application assets behind
a single switch
Network distance introduces
unpredicatability and latency
One
Hop
One
HopVM VM
Traditional Security Models Fail
Traditional security models don’t work well
in a post virtualization world. Like network
connectivity, security architectures were built
for largely static IT infrastructures. Every year,
another threat seems to arise and the conga line
of appliances sit at the drawbridge of the castle
filtering, inspecting, and blocking traffic as it exits
and enters the data center. These appliances
cast a shadow across the network as a whole, if
they can even keep up, or across branches of the
network where a particular security service
is needed.

5. 5
The Infrastructure Evolution Imperative
Just like with changes in application, compute,
and storage, infrastructure architects expect to
get better economics and more agility, efficiency,
and performance for their infrastructure
investments. Cloud and virtualization
technologies are driving the first major change
in data center network architectures in 20 years.
This means the number of options from the
incumbent established vendors and start-ups is
exploding, while the gravity of the decisions data
center architects and network engineers need to
make dictate the future capabilities of their data
center operations.
Managing IT Agility: Choosing data center
network architectures, and the software and
hardware that enable those architectures, has
become a critical task. And there are a number
of challenges that come with the scale of the
environment, the capacity and speeds of server
and storage equipment, and future growth needs.
There are two architectural options for data
centers that seek to optimize the network for
virtualized compute, distributed applications,
and scale-out needs such as big data clusters.
The best option would be indicated based on the
scale and capacity of the environment.
Managing Security: The quandary for any
security architecture is how to reduce risk
without inhibiting the agility of the business,
while at the same time ensuring that the costs
of security don’t increase faster than the growth
in the types of threats that need to be mitigated.
With products like virtual gateways, data center
managers gain visibility and the tools needed to
enforce both physical and virtual flows, and they
can create secure zones that can be enforced
on all flows in a mixed traditional and VMware
environment.
Simplifying the Network: Data center managers
don’t just want a status quo network, or a cheap
network, they want a high performing network
built for a virtualized data center environment.
New network architectures can improve
application performance, while reducing the
network’s footprint and complexity. They can
be optimized for server-to-server and server-
to-storage traffic, and they also enable the use
of network virtualization to replace multiple
dedicated data center-to-data center links with
fewer wide area connections.
Figure 4:
Shadows create
blind spots in a post
virtualization world
Shadow
Shadows worked pre-virtualization
with static apps
Post-virtualization,
traditional security models fail
Shadow
Appliances
and VLANs
Appliances
and VLANs
VM to VM
blind spot
VM VM VM
VM moved outside
assigned VLAN
and security zone

6. 63200014-001-EN Oct 2012
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Key questions to ask:
• Do you have a common operating system and
operational model across your entire data center
network?
• When connecting data centers, can you not
only virtualize multiple networks over a shared
MPLS service, but also enable granular traffic
engineering over each virtualized link, enabling
customers to confidently replace expensive
dedicated links with less expensive MPLS services
or private wide area networks?
• When refreshing 1GbE servers or adding 10GbE
servers, are you able to offload rack-to-rack traffic
and achieve scale that used to require three tiers
of switching with only two tiers? This removal of
the aggregation tier can save up to 30% of CapEx
and OpEx network cost.
• When building a 10GbE server data center or
POD, does your architecture allow you to optimize
for server-to-server and server-to-storage
connectivity? An industry-leading switch fabric
can give you the simplicity of multiple switches
behaving and being managed like a single switch,
very high performance, and the resilience and
scale expected from a network of autonomous
devices.
Conclusion
As IT organizations embrace server virtualization
and move to the cloud, the changes they
make might begin on legacy networks but will
eventually require transformational change.
In the new data center, IT infrastructure will
need to be globally resilient, delivered via cloud
services or by IT from multiple data centers.
The data center network will be optimized for
east-west traffic, and VMs will be able to move
around based on demand, or there will be
one VM per app on shared physical compute.
Virtualized storage and master data initiatives
will dictate common pools of data available to all
applications. Data will be physically connected
to every app, with access governed by policy.
And a pool of network and security services will
be available to all traffic flows, combined with
firewall services built to gain visibility and security
for VM-to-VM traffic without constraining app
performance or compute efficiencies.
This is the promise of the new network as we
move from legacy systems to the efficiencies of
the cloud.