Overview of IBM Networking
IBM Network Media Translation
Cisco’s Implementation of SDLC
Cisco’s SDLC implementation supports the following features:
•Frame Relay Access Support (FRAS)
With FRAS, a router functions as a Frame Relay Access Device (FRAD) for SDLC, Token Ring, and
Frame Relay access support is described in the chapter “Configuring SNA Frame Relay Access Support.”
•SDLLC media translation
The SDLLC feature provides media translation between the serial lines running SDLC and Token Rings running LLC2. SDLLC consolidates the IBM SNA networks running SDLC into a
SDLLC is described in the chapter “Configuring IBM Network Media Translation.”
•SDLC local acknowledgment
SDLC local acknowledgment is used with SDLC STUN. TCP/IP must be enabled. With local acknowledgment, STUN SDLC connections can be terminated locally at the router, eliminating the need for acknowledgments to be sent across a WAN.
SDLC local acknowledgment is described in the section “Establish the Frame Encapsulation Method” in the chapter “Configuring STUN and BSTUN.”
IBM Network Media Translation
The Cisco IOS software includes the following media translation features that enable network communications across heterogeneous media:
•SDLLC media translation enables a device on a Token Ring to communicate with a device on a serial link.
•QLLC conversion enables an IBM device to communicate with an X.25 network without having to install the X.25 software on local IBM equipment.
SDLLC is a Cisco Systems proprietary software feature that enables a device on a Token Ring to communicate with a device on a serial link by translating between LLC2 and SDLC at the link layer.
SNA uses SDLC and LLC2 as link layer protocols to provide a reliable connection. The translation function between these
This section contains a brief overview of IBM Network Media Translation which is described in the following topics:
•SDLLC Media Translation Features, page 220
•QLLC Conversion, page 222
•Cisco’s Implementation of QLLC Conversion, page 223
•Comparing QLLC Conversion to SDLLC, page 224
•Other Implementation Considerations, page 225
Figure 91 illustrates how SDLLC provides data link layer support for SNA communication.
Cisco IOS Bridging and IBM Networking Configuration Guide