Enterprise-Wide Security Architecture and Solutions Presentation Guide

2.3.2 Security Services

Figure 17. Security Services

Key Points

Security services are the key facilities necessary for an enterprise to implement

security controls.

Presentation Script

Security services are those functions that, when provided in a systems

environment, serve to ensure the protection of resources by enforcing the

defined security policies of the organization.

Identification and Authentication:

Identification and Authentication (I&A)

facilities verify the identity of individuals. The basic function uniquely identifies

users and programs, verifies these identities, and assures individual

accountability. Authentication may be single authentication, for an individual

user to the system, mutual authentication of peers, such as two party

authentication for distributed applications, or three party authentication when

dealing with local authentication servers in a distributed environment.

Authenticated user identification provides the basis for additional security

functions, such as access control and auditing. Authentication technology may

take the form of passwords, smart tokens, smart cards, and biometric measuring

devices.

Chapter 2. IBM Security Strategy and Architecture 35

Access Control:

Access control allows the installation to protect critical

resources by limiting access to only authorized and authenticated users.

Depending on the environment, access may be controlled by the resource

owner, or, it may be done automatically by the system through security labels.

The resource owner can specify who can access the information, how it can be

accessed, when it can be accessed, and under what conditions it can be

accessed (for example, when executing specific applications, programs, or

transactions). The functional goal is to assure that security is maintained for

resources, whether they are in a central system, distributed, or mobile (as in the

case with files and programs).

Confidentiality:

Confidentiality protects sensitive information from disclosure.

When it is stored locally, sensitive data can be protected by access controls or

encryption mechanisms. For network communication security, sensitive data

should be encrypted as it is transmitted from system to system. The IBM

architecture for confidentiality is the IBM Common Cryptographic Architecture.

There are specific ISO standards (8730, 8731, and 9564) relating to use of

cryptography for confidentiality and data integrity, which are supported by IBM′s

Common Cryptographic Architecture products: the Transaction Security System,

the Integrated Cryptographic System Facilities/MVS, and the ES/9000 Integrated

Cryptographic Feature.

Data Integrity:

Data integrity provides detection of the unauthorized modification

of data. Organizations must allow for the use of data by authorized users and

applications, as well as the transmission of data for remote processing. Data

integrity facilities can indicate whether information has been altered. Data may

be altered in two ways: because of hardware or transmission errors or because

of an attack. For years, many IBM products have used a checksum mechanism

in disk and tape storage systems and in network protocols to protect against

transmission and hardware errors. Active attacks on data integrity require a

different mechanism, which uses cryptography and allows for the verification of

data integrity.

To address active attacks on data integrity, IBM supports message

authentication based on cryptographic functions that adhere to international

standards. The IBM Common Cryptographic Architecture is the IBM architecture

for data integrity, and it defines functions for both message authentication codes

(MAC) and modification detection codes (MDC).

Non-Repudiation:

Non-repudiation may be viewed as an extension to the

identification and authentication services. The non-repudiation service can

protect a recipient against the false denial by an originator that the data has

been sent, and it can protect an originator against the false denial of a recipient

that the data has been received. In general, non-repudiation applies to the

transmission of electronic data, such as an order to a stock broker to buy/sell

stock; a doctor′s order for medication to a specific patient; or approval to pay an

invoice by a company to its bank. The overall goal is to be able to verify, with

virtually 100% certainty, that a particular message can be associated with a

particular individual, just as a handwritten signature on a bank check is tied back

to the account owner.

36 Security P-Guide