Download - Project Proposal for Integrated Control and Connection management Robby Gurdan and Richard Foss
Motivation
• Integrate control and connection management with a single protocol
• Full physical network independence• Provide security via subnet access control• Incorporate latency control• A need for a distributed server-less system
Challenges
• Many incompatible network standards• A range of devices to control with varying
levels of complexity and capability• Timing constraints with real time audio
streaming• Synchronization between multiple media
stream types• No global security standard for media and
control data
Markets
• Installation market • Live events• MI / home studio• offices• residential• telecommunication• security related systems
Benefits to the Industry and End User
• Full control and streaming interoperability• Consistent user-device interaction• Full system control is possible from small
controllers• Extensive parameter control is possible with
limited messaging• Full backward and forward compatibility• Parameter learning capability
XFN Protocol
• IP-based peer to peer network• Each device will have an IP stack• XFN protocol layer above IP stack– A tree structured parameter hierarchy– Hierarchy reflects structure of device, eg.
• Input section of mixing console• Channel strip• Parameter group• Parameter type, eg gain• Parameter value
Parameter Groupings
• Groupings are natural to audio engineers• Lowest level nodes– Parameter values and formats
• Each parameter - a fixed number of groupings– From parameter level – Up to top-most tree grouping level
Grouping level names
• SECBLK• SECTYPE• SECNR• PARAMETER_BLOCK• PAR_BLOCK_INDEX• PAR_TYPE• PAR_INDEX• VALFT/VALUE
Known Group Object ID’s
• At each level:– Known group object ID’s– Each unique within the level
• Address of a particular parameter– Constituted from seven group object ID’s
• Group objects and ID’s published in specification
Gain Parameter in BBox
• SECBLK SCT_BLOCK_INPUT ID 01• SECTYPE SCT_TYPE_ANALOG ID D4• SECNR STREAMNUMBER ID 100001• PARAMETER_BLOCK PRM_BLK_DGTL_AMP ID 11• PAR_BLOCK_INDEX NUMBERENTRY ID 1• PAR_TYPE GAIN ID 0201• PAR_INDEX PAR_INDEX ID 1• VALFT/VALUE 8 bit/0-255 00/0-255
Isoch Channel Number
• SECBLK SCT_BLOCK_INPUT ID 01• SECTYPE SCT_TYPE_1394 ID
E1• SECNR INTERFACENUMBER ID 0• PARAMETER_BLOCK PRM_BLOCK_MULTICORE ID 11• PAR_BLOCK_INDEX NUMBERENTRY ID
1• PAR_TYPE IsochChannelNumber ID
201• PAR_INDEX Dummy ID• VALFT/VALUE 8 bit/0-255 00/0-255
Tree Structure in each deviceDEVICE
SECBLK
SECTYPE
PARMBLOCK
PARMBLKINDEX
SECNR. . . . . . . . . . . . . . . . . .
PARMTYPE
PARMINDEX
The nodes representparticular objects relevantto the level on which theyappear.
‘Wild card ID’s’
• Wildcard ID may be used in place of:– An object ID– On a particular level
• Selects all objects on next level of tree• Allows for control of:– a large number of parameters – with a single broadcast command
Command Structure
• Each command comprises:– An operand (such as SET or GET)– An operand modifier (such as VAL)– A structured address comprising level ID’s– A format indicator and value
Level Commands
• To trace through the tree structure:– Use ‘Level’ commands
• For any node of a tree:– Return sub-nodes below the node
• Allows discovery of parameters
• Provide this address
• Return these nodes
Parameter Index Values
• A device holds a parameter index value– For each parameter it contains
• Controller can request index– Via a ‘get index’ command– With an associated structure address– Device provides index to controller
• Controller uses index instead of address
Joins
• Parameters can be joined into groups• Change one parameter of the group– All other parameters of group change
• Joins can be:– Absolute or relative– Unidirectional or bidirectional
Join mechanism
Bidirectional Group – Parameter changes are sent
between all joined parameters
Unidirectional Group – Parameter changes are sent only in a single
direction
Modifiers
• Provide the capability to selectively modify one or more settings within a command– Settings are modified at any level of command– Command can be:• Directed at a parameter• Emanating from a parameter
Across Bus Transmission?
• Currently the IEEE 1394.1 specification• No implementations• Problems:– Devices must be bridge aware– All asynchronous packets are passed• No control mechanisms (security)
– No re-bundling of packets
Media Stream Routing
• Allows control over– The receipt of isochronous multimedia streams• Via a portal• On same bus as transmitter
– The extraction of sequences and re-bundling of sequences• For transmission over co-portal
– The configuration of transmitted isochronous streams
IP Routing
• Creation of an IP address for each portal of the router
• Creation of an IP routing table – each entry:– A subnet (corresponding to a bus)– A subnet mask– A router interface to send to– IP address of gateway if address not on local bus