1.1 Glossary


This document uses the following terms:

account: A collection of data and settings for a SharePoint Workspace or Groove identity that represents a user. This includes shared spaces, messages, and preferences that are associated with a user's identity. An account can reside on one or more devices.

account key: A secret key that is shared between a relay server and a client account for account authentication (2). A protocol client generates this key when it creates a new account, and then registers this key on a relay server through a registration sequence. The relay server uses this key to authenticate the account and enable the protocol client to retrieve identity-targeted messages from the server.

account URL: A unique identifier for an account, as described in [RFC3986].

American National Standards Institute (ANSI) character set: A character set defined by a code page approved by the American National Standards Institute (ANSI). The term "ANSI" as used to signify Windows code pages is a historical reference and a misnomer that persists in the Windows community. The source of this misnomer stems from the fact that the Windows code page 1252 was originally based on an ANSI draft, which became International Organization for Standardization (ISO) Standard 8859-1 [ISO/IEC-8859-1]. In Windows, the ANSI character set can be any of the following code pages: 1252, 1250, 1251, 1253, 1254, 1255, 1256, 1257, 1258, 874, 932, 936, 949, or 950. For example, "ANSI application" is usually a reference to a non-Unicode or code-page-based application. Therefore, "ANSI character set" is often misused to refer to one of the character sets defined by a Windows code page that can be used as an active system code page; for example, character sets defined by code page 1252 or character sets defined by code page 950. Windows is now based on Unicode, so the use of ANSI character sets is strongly discouraged unless they are used to interoperate with legacy applications or legacy data.

ASN.1: Abstract Syntax Notation One. ASN.1 is used to describe Kerberos datagrams as a sequence of components, sent in messages. ASN.1 is described in the following specifications: [ITUX660] for general procedures; [ITUX680] for syntax specification, and [ITUX690] for the Basic Encoding Rules (BER), Canonical Encoding Rules (CER), and Distinguished Encoding Rules (DER) encoding rules.

certificate: A certificate is a collection of attributes (1) and extensions that can be stored persistently. The set of attributes in a certificate can vary depending on the intended usage of the certificate. A certificate securely binds a public key to the entity that holds the corresponding private key. A certificate is commonly used for authentication (2) and secure exchange of information on open networks, such as the Internet, extranets, and intranets. Certificates are digitally signed by the issuing certification authority (CA) and can be issued for a user, a computer, or a service. The most widely accepted format for certificates is defined by the ITU-T X.509 version 3 international standards. For more information about attributes and extensions, see [RFC3280] and [X509] sections 7 and 8.

challenge: A piece of data used to authenticate a user. Typically a challenge takes the form of a nonce.

connection: A link between two devices that uses the Simple Symmetric Transport Protocol (SSTP). Each connection can support one or more SSTP sessions.

device: A client or server computer that uses a device URL to identify itself as an endpoint (5) for synchronizing account data.

device key: A secret key that is shared between a relay server and a client device for device authentication (2).

device URL: A unique identifier for a client device, as described in [RFC3986].

device-targeted message: A message with an intended destination of a specific resource handler, identity, and client device combination. A device-targeted message is sent over a session addressed by a tuple of resource URL, identity URL, and client device URL.

Distinguished Encoding Rules (DER): A method for encoding a data object based on Basic Encoding Rules (BER) encoding but with additional constraints. DER is used to encode X.509 certificates that need to be digitally signed or to have their signatures verified.

ElGamal encryption: A public-key encryption scheme, as described in [CRYPTO].

identity: A digital persona that is associated with two key pairs, one for encrypting data and another for signing data.

identity URL: A string of characters that uniquely identifies an identity and conforms to the syntax of a URI, as described in [RFC3986].

identity-targeted message: A message that is destined for a specific resource handler and identity combination, regardless of the client device. The message address includes a resource URL, identity URL, and client device URL, where the client device URL is empty.

keyed-hash Message Authentication Code: A symmetric keyed hashing algorithm used to verify the integrity of data to help ensure it has not been modified while in storage or transit.

little-endian: Multiple-byte values that are byte-ordered with the least significant byte stored in the memory location with the lowest address.

management server: A server application that is used to manage SharePoint Workspace and Groove identities and services.

Modified Alleged Rivest Cipher 4 (MARC4) algorithm: A variable, key-length, symmetric encryption algorithm that discards the first 256 bytes of a keystream.

network address translation (NAT): The process of converting between IP addresses used within an intranet, or other private network, and Internet IP addresses.

nonce: A number that is used only once. This is typically implemented as a random number large enough that the probability of number reuse is extremely small. A nonce is used in authentication protocols to prevent replay attacks. For more information, see [RFC2617].

object identifier (OID): In the context of a directory service, a number identifying an object class or attribute (2). Object identifiers are issued by the ITU and form a hierarchy. An OID is represented as a dotted decimal string (for example, ""). For more information on OIDs, see [X660] and [RFC3280] Appendix A. OIDs are used to uniquely identify certificate templates available to the certification authority (CA). Within a certificate, OIDs are used to identify standard extensions, as described in [RFC3280] section 4.2.1.x, as well as non-standard extensions.

private key: One of a pair of keys used in public-key cryptography. The private key is kept secret and is used to decrypt data that has been encrypted with the corresponding public key. For an introduction to this concept, see [CRYPTO] section 1.8 and [IEEE1363] section 3.1.

public key: One of a pair of keys used in public-key cryptography. The public key is distributed freely and published as part of a digital certificate. For an introduction to this concept, see [CRYPTO] section 1.8 and [IEEE1363] section 3.1.

RC4: A variable key-length symmetric encryption algorithm. For more information, see [SCHNEIER] section 17.1.

relay server: A server application that provides message transmission services for Simple Symmetric Transport Protocol (SSTP) messages.

relay URL: A string of characters that uniquely identifies a relay server and conforms to the syntax of a URI, as described in [RFC3986].

secret key: A symmetric encryption key shared by two entities, such as between a user and the domain controller (DC), with a long lifetime. A password is a common example of a secret key. When used in a context that implies Kerberos only, a principal's secret key.

session: A unidirectional communication channel for a stream of messages that are addressed to one or more destinations. A destination is specified by a resource URL, an identity URL, and a device URL. More than one session can be multiplexed over a single connection.

SHA-1 hash: A hashing algorithm as specified in [FIPS180-2] that was developed by the National Institute of Standards and Technology (NIST) and the National Security Agency (NSA).

Simple Symmetric Transport Protocol (SSTP): A protocol that enables two applications to engage in bi-directional, asynchronous communication. SSTP supports multiple application endpoints (5) over a single network connection between client nodes.

symmetric key: A secret key used with a cryptographic symmetric algorithm. The key needs to be known to all communicating parties. For an introduction to this concept, see [CRYPTO] section 1.5.

Unicode: A character encoding standard developed by the Unicode Consortium that represents almost all of the written languages of the world. The Unicode standard [UNICODE5.0.0/2007] provides three forms (UTF-8, UTF-16, and UTF-32) and seven schemes (UTF-8, UTF-16, UTF-16 BE, UTF-16 LE, UTF-32, UTF-32 LE, and UTF-32 BE).

X.509: An ITU-T standard for public key infrastructure subsequently adapted by the IETF, as specified in [RFC3280].

MAY, SHOULD, MUST, SHOULD NOT, MUST NOT: These terms (in all caps) are used as defined in [RFC2119]. All statements of optional behavior use either MAY, SHOULD, or SHOULD NOT.