Intel Ethernet Cloud White Paper

hypervisor. While 10GbE typically provides
ample bandwidth for these multiple trafc
streams to coexist, policies must be put in
place to ensure appropriate allocation of
network resources in the event of trafc
spikes and congestion.
Bandwidth limiting within a VM or virtual
switch enables separate guarantees to be
set up on a per-VM (per-customer) basis.
They can be controlled either in software
or in hardware. VMware and Microsoft
Hyper-V* enable I/O limiting from the
hypervisor, whereas Xen* and KVM enable
I/O limiting from the hardware/driver. Intel
Ethernet supports hardware-based rate
limiting in the network controller on a
per-VM basis. This exibility adds further
to the ability of the IT organization to
tailor services to the needs of individual
customer groups.
QoS support with Intel Ethernet 10Gb
Server Adapters works by means of
virtual network adapters. Intel Ethernet
controllers dynamically assign bandwidth
to meet QoS requirements using the
following features and capabilities:
• 
 assigns time slices to each
VF in equal portions and in a circular
fashion for Rx/Tx operations.
•  enables the virtual
Ethernet bridge to sort and classify
traffic into VFs or queues.
•  throttles the
rate at which a VF can transmit data.
•  assigns each process
or VM a VF with VLAN support.
•  enables the
Virtual Ethernet Bridge to conduct PCI
Express speed switching between VMs.

To fully realize the agility and cost benets associated with cloud computing, IT departments must incorporate into their
architectures best practices such as those described in this paper:
 Consolidating multiple GbE server adapters onto 10GbE
further simplies the environment, for easier management and lower risk of device failure. The increased bandwidth available
from 10GbE also improves handling of workload peaks.
 Using iSCSI or FCoE on Intel Ethernet Server Adapters
instead of native Fibre Channel to pass storage trafc reduces the capital expense associated with buying host bus adapters and
the higher per-port cost of Fibre Channel switching. It also reduces power requirements and simplies the overall environment by
reducing two separate fabrics to just one.
 Using Intel VT-c capabilities, including VMDq and
SR-IOV support, ofoads packet switching and sorting from the processor to the network silicon, making processor resources
available for other work.
 Because Intel Ethernet Server Adapters
support both VMDq and SR-IOV technologies, they can provide the functionality required by various hypervisors, for optimal
hardware exibility.
 Features built into Intel Ethernet Server Adapters also provide
excellent support for QoS, dynamically assigning bandwidth as needed to various trafc classes. This functionality is a key
component of being able to provide needed service levels to multiple clients in a multi-tenant environment.
Best practices to implement an optimized, reliable private cloud network using Intel Ethernet 10 Gigabit Server Adapters enable
IT departments to better align their strategies with those of the business as a whole. As a result, IT is more efcient at building
success for its customer organizations.
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