Artesyn PCIE-8120 Installation and Use (July 2014) - Manual (Page 23)

Chapter 2
PCIE-8120 Installation and Use (6806800R89C) 23
Functional Description
2.1 Overview
PCIE-8120 is based on the Octasic OCT2224M multi-core DSP running Vocallo MGW firmware.
The DSP array performs media processing acceleration for a host server, supporting both voice
and video conferencing and transcode applications.
Media acceleration performance depends on both the codecs required and the number of
DSPs available. A variety of board configurations allow differences in application needs and
server capabilities, and include a choice of 4, 8 and 12 DSPs, with maximum power
consumption between 25W and 65W.
NOTE: An external power connector option is available only for NEBS variant.
Media streams for transcoding are typically RTP/UDP/IP streams that go to the DSP array. The
functions that can be applied to each media stream are determined by the capabilities of the
Vocallo MGW firmware. For more information on the media processing functions, see PCIE-
8120 Data Sheet.
Media streams can be routed to the DSPs either via the host CPU or optionally via two external
Gigabit Ethernet ports provided for direct traffic termination. In this configuration, packets for
transcode can bypass the host computer entirely, while a special Network Address Translation
(NAT) device makes the board appear as a single IP address to external networks.
2.2 Programming Model
The internal data flows of the board are all based on Gigabit Ethernet connections with all DSPs
accessible via a local Ethernet switching subsystem. Host access to all the DSPs is via a 2 x 1Gb/s
PCI Ethernet controller. The Ethernet switching subsystem also supports two 1Gb/s links to
each DSP to support special 1080p video conferencing modes. Based on the number of DSPs,
this is provided by either one or two on-board Ethernet switches. For more details, see the
block diagrams in
PCIE-8120 Hardware Description on page 55 . For most applications, this detail
is invisible to the application.
A comprehensive host-based Media Processing Application Programmers Interface is
provided. This is used to configure and execute voice and video stream processing functions on
the DSPs. The API commands communicate directly with the DSP array based on an endpoint
and stream resource model. A non-blocking command/response protocol supports multi-
channel programming efficiency.