Specifications

72 IBM Voice Over Frame Relay Perform Guide
4.1.12 FRF.11
FRF.11 was defined to extend FR support to the transportation of digital voice
payloads. The frame format and procedures are defined in this implementation
agreement (IA). The specification addresses the following requirements:
• Transport of compressed voice within the payload of a FR frame
• Support for a diverse set of voice compression algorithms
• Effective utilization of low-bit FR connections
• Multiplexing of up to 255 subchannels on a single FR DLCI
• Support for multiple voice payloads on the same or different subchannel within
asingleframe
• Support for data-channels on a multiplexed FR DLCI.
See 1.1, “Standards-Based Transport over Frame Relay” on page 1 for details.
4.1.13 FRF.12
The FRF.12 Implementation Agreement (also known as FRF.11 Annex C) was
developed to allow long data frames to be fragmented into smaller pieces and
interleaved with real-time frames. In this way, real-time voice and non real-time
data frames can be carried together on lower speed links without causing
excessive delay to the real-time traffic.
Figure 43. Without FRF.12 and without BRS Super-Class
Figure 44. FRF.12 and BRS Super-Class
IBM
Voice
Data
IBM
Voice
Data
BRS Super-class : Urgent
BRS : Normal
Voice Frame has Super-Class
Urgent priority
IBM 2212