Since the publication of the last entry on cloud security, I received many emails from clients and colleagues who have an interest in this topic. Because of the sensitive nature of the topic, they chose to email me rather than leaving a comment here. I have synthesized and sanitized the feedback, and decided to publish the summary here:
a) Investigation support: A few responses stressed the importance of support for enterprise investigation. They voiced frustration with the lack of timely response and technical support from some of the cloud vendors. One senior IT officer said: “For every investigation, I have to work with the vendor to get the data I want. They don’t have an option for me to be the administrator of my users’ data and logs. This goes against the self-service nature of cloud computing, and essentially takes away some of the benefits”.
b) Security and privacy are equally important for all layers of cloud, as customers may be buying a combination of services (of different layers) from the same provider. The so-called ”layers of cloud” include infrastructure-as-a-service(IAAS), platform-as-a-service (PAAS), and software-as-a-service (SAAS). Each layer may have its own unique challenge.
c) Incident response and disclosure: Readers pointed out that you may want to know that a data breach has happened within the cloud environment even though your data may not be breached. This is a tough issue because from the users’ standpoint, you want to know the incidents so you can make an informed decision whether to stay with the cloud. But on the flip side, you may not want the provider to offer too much information to other clients if it were your data that were breached. There is no standard procedures today people follow for incident disclosures that impact other people’s data.
d) Compliance: Some compliance requirements demand that relevant data be encrypted both at rest and in transit. Many of the cloud providers do not support that and in some cases due to the way the application is configured, encryption by the customer of the cloud is also not an option. For instance, some cloud applications leave sensitive information in the database index, which is typically not encrypted even if the blocks are encrypted. In this case, having block-based encryption is clearly not sufficient.