OSI/MHS Management Programming Manual
Glossary
OSI/MHS Management Programming Manual—424824-001
Glossary-12
layer
layer. A grouping of related functions in the OSI Reference Model. See Application Layer, 
Data Link Layer, Network Layer, Physical Layer, Presentation Layer, Session Layer, or 
Transport Layer.
link. A physical and logical path between two adjacent computers or other devices.
In OSI/MHS, a pair of OSI addresses that are configured for each MTA. A pair of OSI 
addresses is a set of local and remote address definitions in the MTA object representing 
an adjacent MTA.
link retry. The action taken when a line to an adjacent MTA fails or is unavailable. All other 
links to that MTA are tried. You set the time available to establish the association 
through the CLASS attribute LINK-RETRY-TIME. You set the time to wait before an 
MR group can retry the previously failed association through the CLASS attribute 
LINK-RETRY-DELAY.
LO (local operations) class. The OSI/MHS CLASS object that identifies the set of all LO 
groups in a Compaq OSI/MHS subsystem.
LO (local operations) group. The OSI/MHS group that implements the local operations 
function, giving local user agents access to an X.400 network through a message store. 
The LO group consists of a single LO process and a PDU store. There can be zero, one, 
or more LO groups in a single OSI/MHS subsystem. There must be at least one LO 
group for the P7 API to connect with OSI/MHS.
LO (local operations) process. The process in the LO group that provides local functions 
analogous those of the Remote Operations Service Element (ROSE) defined in OSI. 
The LO process manages associations from local client applications and creates PDUs in 
the MR or MS PDU stores during submit operations.
local identifier. A unique identifier that distinguishes an object from all other 
communications ever originated by the originating management domain; an attribute of 
the MTS identifier object. A local identifier is generated by the GPI when a client 
program transfers a communication out to the GPI service.
local user agent. See LUA.
logical MTA. All of the MR groups in an OSI/MHS subsystem.
long string. In the GPI, a string that cannot be passed in an attribute descriptor but must be 
manipulated a segment at a time by using the GPI_OM_READ_ and GPI_OM_WRITE_ 
procedures. At GPI initialization, a client program specifies the maximum length string 
that can be passed in a descriptor. All strings longer than the specified maximum are 
long strings.
LUA (local user agent). A process that submits and retrieves messages on behalf of a user, 
through a message store on the same system as the user agent.
mailbox. A location in an MS SQL database that stores messages for one user. Each MS 
group can have up to 1000 mailboxes to support up to 1000 users.










