The Local Transcoding Interface (LTI) was a Cisco Unified Border Element (CUBE) transcoding feature originally introduced on Aggregation Services Routers (ASR) platform in 15.1(1)S. Starting with CUBE 9.0, this feature was added to ISR G2 platforms with additional enhancements. LTI includes an internal API to access digital signal processor (DSP) resources. This API bypasses the need for CME configuration and licensing, as well as the use of Skinny Client Control Protocol (SCCP). When both LTI-based and SCCP-based transcoding are configured, LTI takes precedence.
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Local Transcoding Interface (LTI)
The information in this document is based on Cisco Unified Border Element (CUBE) 9.0.
Comparison with SCCP-based Transcoding
CME/SCCP based Xcoding
LTI based Xcoding
SCCP protocol is used for controlling DSP resources used for transcoding.
Internal API are used to access DSP resources for transcoding.
Transcoding resources (DSPFARM) and CUBE can be on different platforms.
Transcoding resources (DSPFARM) and CUBE need to be on the same platform.
SCCP client (SCCP CCM...) configuration and SCCP server (telephony service) configuration is required for CUBE-Ent configuration apart from DSPFARM profile configuration.
Only DSPFARM profile configuration is required. SCCP configuration and CUCME configuration is not required when used with CUBE-Ent.
DSPFARM registers with CUCME over TCP socket, using SCCP.
No TCP socket is opened and no registration is used.
!--- Only dspfarm profile configurations are needed for !--- LTI-based transcoding. All the SCCP-based transcoding !--- features will be supported with LTI-based transcoding.
CUBE#show dspfarm profile 1 Dspfarm Profile Configuration Profile ID = 1, Service =Universal TRANSCODING, Resource ID = 1 Profile Description : Profile Service Mode : Non Secure Profile Admin State : UP Profile Operation State : ACTIVE << Profile 1 is ACTIVE Application : CUBE Status : ASSOCIATED << Profile 1 (LTI) is associated with CUBE application Resource Provider : FLEX_DSPRM Status : UP Number of Resource Configured : 12 Number of Resources Out of Service : 0 Number of Resources Active : 0 Codec Configuration: num_of_codecs:5 Codec : g729ar8, Maximum Packetization Period : 60 Codec : g729br8, Maximum Packetization Period : 60 Codec : g711alaw, Maximum Packetization Period : 30 Codec : g711ulaw, Maximum Packetization Period : 30 Codec : g729r8, Maximum Packetization Period : 60