Ncia – IBM BC-203 User Manual
Page 26
Overview of IBM Networking
NCIA
BC-228
Cisco IOS Bridging and IBM Networking Configuration Guide
Figure 100
RFC 1490 Bridged Frame Format
Because it includes the MAC header information in every frame, BAN supports multiple SNA devices
sharing a single permanent virtual circuit without requiring SAP multiplexing. BAN also supports load
balancing across duplicate data-link connection identifiers to the same or different front-end processors
at the data center to enhance overall availability. BAN works for devices attached by either Token Ring
or Ethernet.
NCIA
Native Client Interface Architecture (NCIA) is a new software architecture introduced by Cisco to make
accessing IBM SNA applications over routed internetworks more scalable and flexible. NCIA is a
component of the Cisco IOS software. The architecture is intended to combine the benefits of the native
SNA interface at end stations and mainframes with those of TCP/IP across the network backbone.
NCIA extends the use of the TCP/IP protocol all the way to the SNA end station. Because of the wide
range of media supported by TCP/IP, including dialup telephone lines for remotely located users, NCIA
makes multiprotocol access to corporate backbone networks much more flexible for SNA users.
NCIA allows SNA end stations such as PCs or workstations to encapsulate SNA traffic in TCP/IP, rather
than requiring the traffic to travel through routers. The first phase of NCIA (NCIA I), used Cisco RSRB
encapsulation. The current phase (NCIA Server) uses a new client/server model. NCIA Server is not
backward compatible to NCIA I.
This section contains a brief overview of NCIA which is described in the following topics:
•
•
•
Advantages of the Client/Server Model, page 231
H7115
Q.922 Address
OUI 0x80-C2 (bridged)
PID 0x00-09
Destination/Source MAC (12 bytes)
Control
SNA Data
PCS
pad 0x00
Frame Control
DSAP
SSAP
NLPID
SNAP 0x80
OUI
00x0
Control
0x03
pad
0x00