S

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SAS

Secure Attention Sequence. The CTRL/Alt/Del key sequence used to begin a login or authentication sequence.

Schema

The definition of all the object types and attributes that can be stored by the AD. Exchange extends the schema to add definitions of its own attributes, such as mailbox quotas.

SID

Security identifier. A unique number that identifies a user or group within a Windows domain.

Signed data

Data with a digital certificate attached as proof of origin or authenticity.

Site

A collection of DCs that share a high-speed (LAN quality) network and defined by one or more IP subnets. Sites also define locality for client workstations. Similar in concept and definition to the term used by previous versions of Exchange.

Site connector

The link over which replication between two sites occurs. You can use TCP/IP or SMTP links for this purpose.

Site link

A means of weighing the relative cost of replication between sites.

SMB

Simple Message Block.

SMP

Symmetric Multiprocessing.

SMS

Short Message Service, a method of sending messages between cell phones over the GSM/GPRS standard. An alternate definition is System Management Server, a Microsoft product designed to simplify management tasks such as software distribution and inventory.

SMTP

Simple Mail Transport Protocol.

Snap-in

A management object that can be added to the MMC to perform specific tasks, such as Exchange system management or AD user management.

SOA RR

A DNS Start of Authority Resource Record.

SRS

Site Replication Services. The ADC component that replicates site configuration data between Exchange 2000/2003 and downstream Exchange servers.

SSL

Secure Sockets Layer.

SSP

Security Support Provider. Windows supports plug-in security services. Windows NT only supports NTLM, but Windows 2000 supports Kerberos, PKI, and NTLM.

SSPI

Security Support Provider Interface. The API used by applications to access SSPs such as Kerberos.

STM

Streaming file or database. Exchange directs incoming Internet content to this repository, which holds messages generated by Internet (IMAP, POP3) clients.

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