IBM BC-201 ユーザーズマニュアル

Using a client/server model allows the NCIA Server feature to be independent of the upstream 
implementation, allowing it to be implemented in a network that is still using RSRB and in a DLSw+ 
network. It also greatly simplifies migration from RSRB to DLSw+, because it requires no changes at 
the client. A single NCIA server can support either approach (but not both). As 

 illustrates, a 

central site router can support RSRB and DLSw+ concurrently, allowing a portion of the NCIA servers 
to communicate using RSRB and another portion to communicate using DLSw+.

The Airline Product Set (ALPS) is a tunneling mechanism that transports airline protocol data across a 
TCP/IP network to a mainframe. ALPS provides connectivity between agent set control units (ASCUs) 
and a mainframe host that runs the airline reservation system.

 shows the basic ALPS topology and the protocols implemented in the feature. Three major 

components provide the end-to-end transportation of airline protocol traffic across the network: the 
P1024B Airline Control (ALC) or P1024C (UTS) protocol, the TCP/IP-based MATIP protocol 
conversion, and the TCP/IP access to the mainframe.

Mainframe

with FEP

Cisco

RSRB/DLSw+

DLSw+

NCIA server

NCIA server

51915

IP

backbone

RSRB

Client

workstation

Token

Ring

Token

Ring

Router peers

Computing center