Page 282 - Cloud computing: From paradigm to operation

1 Framework and requirements for cloud computing

Appendix IV

Considerations on supporting of ETS
(This appendix does not form an integral part of this Recommendation.)

[b-ITU-T Y.1271] specifies the network requirements and capabilities to support ETS over both circuit-
switched and packet-switched networks. Annex A of [b-ITU-T Y.1271] contains the list of functional
requirements and categorizes them as essential and optional. Support for these requirements is needed for
the scenario of when an ETS is offered by the CSP.
The requirements in [b-ITU-T Y.1271] can be separated into those relevant to the networking resources and
those relevant to core transport network(s). Some requirements are applicable both for resources and for
transport network(s). This clause considers the requirements for the networking resources category using
the general requirements in clauses 8.1 and 8.2. The requirements relevant for networking resources from
[b-ITU-T Y.1271] include: enhanced priority treatment, location confidentiality, restorability, interoperability,
survivability/endurability, scalable bandwidth, reliability/availability and preferential treatment in
congestion control measurement.
A cloud supporting ETS needs to be robust and able to support customers despite widespread damage.
Another requirement is the restoration of access to cloud infrastructure resources including links connecting
to the cloud. The processing nodes (virtual or physical) are to be restored quickly if damage to infrastructure
resources occurs.
Cloud infrastructure resources need to adapt quickly for emergency applications, an adaptation that equates
to application acceleration as noted in clause 8.1. Because ETS have requirements for different policies (QoS,
security, traffic), the migration requirements in clause 8.1.5 are necessary to guarantee the SLAs among ETS
customers and their CSPs.
The requirements, from [b-ITU-T Y.1271], specifically relevant to the support of ETS in core networks include:
secure networks, restorability, network connectivity, mobility, coverage, survivability (connections), voice
and data transmission, scalable bandwidth and reliability. Some of these requirements are applicable to both
networking resources and the core transport network.

The requirements of clause 8.1, in relation to ETS, apply to ubiquitous coverage and therefore have the
potential to preclude the need to establish special facilities after the occurrence of an emergency or disaster.

Reliability considerations of clause 8.1, in relation to ETS, are necessary for the network infrastructure to
support survivability and endurability.
In support of ETS, the network should be smart enough for high priority applications. Some aspects of cloud
services may be applicable to the offerings of priority services to facilitate disaster recovery functions, such
as locating survivors and providing vital situational awareness information to government first responders
and relatives of survivors affected by a disaster. Cloud computing can support complex modelling, analysis
and rendering images to the first responders of disasters. [b-Tohoku]
Rapid authentication of authorized users for ETS implies awareness of the user/terminal attributes
(subscriber profile data) and at the same time prevents unauthorized access, denial of service attacks and
protection from intrusion.

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