Chapter 1
41
SNA Terms and Concepts
Basic SNA Concepts
A logical record consists of a two- or four-byte header starting with a
two-byte length field, often represented as “LL,” followed by up to
32,765 bytes of data. Logical records can be grouped together and
sent as a block, transmitting more than one logical record with a
single call to the
SEND
function.
• In a mapped conversation, information is passed to the
SEND
function
as a pointer to a single, unformatted block of data; the length of the
block is passed as another parameter. The block cannot be received as
one or more logical records; the receiving TP must do whatever
record-level formatting is required.
NOTE
Only LU type 6.2 supports mapped conversations.
Modes
Each LU-LU session has an associated mode that defines a set of session
characteristics. These session characteristics include throughput
parameters, session limits (such as the maximum number of sessions
between two LUs), message sizes, and routing parameters.
Each mode is identified by a unique mode name. The mode name must be
the same on all SNA nodes that use that mode.
Route Selection
To establish an LU-LU session, a route must be calculated between the
nodes where the two LUs reside. A route is an ordered sequence of links
and nodes that represents a path between the two nodes.
SNA networks support the following methods of route selection:
• For subarea networks, you must predefine all routes between subarea
nodes.
• For peer networks that do not support APPN, type 2.1 nodes can
support sessions only with adjacent nodes; their sessions cannot be
routed through intermediate nodes.
• For APPN networks, SNA can compute routes dynamically at the
time of session initiation, using a class of service specified for the
mode used by the session (see “Class of Service”).
Содержание HP-UX SNAplus2
Страница 4: ...4 ...
Страница 14: ...14 Contents ...
Страница 22: ...22 ...
Страница 23: ...23 1 SNA Terms and Concepts ...
Страница 65: ...65 2 Introduction to SNAplus2 ...
Страница 107: ...107 3 Administering SNAplus2 ...
Страница 132: ...132 Chapter3 Administering SNAplus2 Using the Command Line Administration Program ...
Страница 133: ...133 4 Basic Configuration Tasks ...
Страница 142: ...142 Chapter4 Basic Configuration Tasks Configuring Logging ...
Страница 143: ...143 5 Defining Connectivity Components ...
Страница 167: ...167 6 Configuring Dependent LUs ...
Страница 174: ...174 Chapter6 Configuring Dependent LUs Defining LU Pools ...
Страница 175: ...175 7 Configuring APPC Communication ...
Страница 208: ...208 Chapter7 Configuring APPC Communication Configuring APPC Security ...
Страница 209: ...209 8 Configuring User Applications ...
Страница 222: ...222 Chapter8 Configuring User Applications Configuring RJE Workstations ...
Страница 223: ...223 9 Configuring Passthrough Services ...
Страница 235: ...235 10 Managing SNAplus2 from NetView ...
Страница 248: ...248 Chapter10 Managing SNAplus2 from NetView Using UCF ...
Страница 249: ...249 11 Managing SNAplus2 Clients ...
Страница 300: ...300 Chapter11 Managing SNAplus2 Clients Managing HP UX Clients ...
Страница 301: ...301 A Configuration Planning Worksheets ...
Страница 337: ...337 B APPN Network Management Using the Simple Network Management Protocol ...
Страница 343: ...343 C Configuring an Invokable TP Using snaptpinstall ...
Страница 353: ...353 D Using SNAplus2 in a High Availability Environment ...