IBM BC-203 Network Hardware User Manual


 
Overview of IBM Networking
IBM Network Media Translation
BC-225
Cisco IOS Bridging and IBM Networking Configuration Guide
circuits (PVCs) are available, but the favored use is SVC. While the router maintains a permanent
connection to the X.25 network, a remote device can use each SVC for some bounded period of time and
then relinquish it for use by another device. Using a PVC is very much like using a leased line.
Table 3 shows how the QLLC commands correspond to the SDLLC commands.
Other Implementation Considerations
Consider the following when implementing QLLC conversion:
To use the QLLC conversion feature, a router must have a physical link to an X.25 public data
network (PDN). It must also have an SRB/RSRB path to an IBM FEP. This link could be a Token
Ring or Ethernet interface, or even FDDI, if RSRB is being used.
QLLC conversion can run on any router with at least one serial interface configured for X.25
communication and at least one other interface configured for SRB or RSRB.
QLLC conversion security depends upon access control in SRB/RSRB and X.25 and upon XID
validation.
You can configure DLSw+ for QLLC connectivity, which enables the following scenarios:
Remote LAN-attached devices (physical units) or SDLC-attached devices can access an FEP or an
AS/400 over an X.25 network.
Remote X.25-attached SNA devices can access an FEP or an AS/400 over a Token Ring or over
SDLC.
For information on configuring DLSw+ for QLLC conversion, refer to the “Configuring DLSw+”
chapter.
You can configure DSPUs for QLLC. For more information on this configuration, refer to the
“Configuring DSPU and SNA Service Point” chapter.
Table 3 QLLC and SDLLC Command Comparison
QLLC Command Analogous SDLLC Command
qllc largest-packet sdllc ring-largest-frame, sdllc
sdlc-largest-frame
qllc partner sdllc partner
qllc sap sdllc sap
qllc srb, x25 map qllc, x25 pvc qllc sdllc traddr
qllc xid sdllc xid
source-bridge qllc-local-ack source-bridge sdllc-local-ack