View
216
Download
0
Category
Preview:
Citation preview
Andy Rayner, Chief Technologistarayner@nevion.com +44 7711 196609
ST2110 – the emerging standard and its practical application
Networking the moving picture II2nd November 2017 10am-4pm
London transport museum
nevion.com/news/events/network-moving-picture-2/
‘Composite’ transport
Different timing domains - adaptive
Comprehensive Protection
Mature – 15+ years
WAN
‘Essence’ transport
Common timing domain – SMPTE2059
Protection?
In its infancy – still maturing
CAMPUS
ST2110-10
• 1460 UDP octets with 8060 octets option
• Multicast with IGMP and Unicast
• IPv4 & IPv6
• PTP to SMPTE ST 2059-2 with SMPTE ST 2059-1 Epoch
• RTP clocks & timestamps locked to media clock
• Zero offset on timestamp mandated
• One SDP object (IETF RFC 4566) per RTP Stream
• 90kHz RTP clock
SYSTEM
ST2110-20
• RTP based
• Subset of RFC4175
• Watch out for line numbering!
• Sampling YCbCr-4:4:4, YCbCr-4:2:2, YCbCr-4:2:0, ICtCp-4:4:4, ICtCp-4:2:2, ICtCp-4:2:0
• Bit depth 8, 10, 12, 16, 16f
• Colorimetry BT601, BT709, BT2020, BT2100, ST2065-1, ST2065-3, DCI-D65, DCI-D60
• TCS (Transfer Characteristic System): “SDR” “PQ” “HLG” “LINEAR” “DENSITY”
VIDEO
ST2110-30
• Based on AES67
• 24 bit linear PCM, 48kHz or 96 kHz
• 1ms packet period with option of 125us
• Up to 8 audio channels per stream – with option of up to 80
AUDIO
ST2110-40
ANCDATA
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|V=2|P|X| CC |M| PT | sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| synchronization source (SSRC) identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Sequence Number | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ANC_Count | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C| Line_Number | Horizontal_Offset | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DID | SDID | Data_Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| User_Data_Words...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum_Word | word_align |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C| Line_Number | Horizontal_Offset | reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DID | SDID | Data_Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| User_Data_Words...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum_Word |word_align |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
• Based on (IETF) RFC RTP Payload for SMPTE ST 291 Ancillary Data
Media Synchronisation history – frequency & phase alignment
GENLOCKBlack burst/tri-level syncFREQUENCY
& PHASE ALIGNMENT
SMPTE 2059using PTPIEEE 1588
Sub uS accuracyFREQUENCY
& PHASE ALIGNMENT
PTP
→ scalability→ security
PTPMaster
PTPMaster
TransparentSwitch
BoundarySwitch
BoundarySwitch
BoundarySwitch
TransparentSwitch
TransparentSwitch
TransparentSwitch
TransparentSwitch
TransparentSwitch
Device Device Device Device Device Device DeviceDevice Device
Scaling the number of media flows
1 x SMPTE2022-6
1 x ST2110-2016 x ST2110-303 x ST2110-40
= 20 flows!
AUDIOVIDEOANCDATA
42 42
Linear stream flows – our raster & hardware heritage
Sample nSample
n+1Sample
n+2Sample
n+3Sample
n+4Sample
n+5Sample
n+6Sample
n+7Sample
n+8Sample
n+9Sample n+10
Sample n+11
Sample n+12
Sample n+13
Sample n+14
Sample n+15
Packet xPacket x+1
Packet x+2
45 45
Inherently less-linear flows…….
• High bit rate video necessitates careful control & shaping.
• SMPTE 2022-6 -> SMPTE 2110 already creates non linearity
VBI ACTIVE FRAME
LINEARISED FLOW
HBI ACTIVE LINE
LINEARISED FLOW
47 47
Narrow & Wide senders
NarrowTypically hardware based
Linked to linear raster-based videoSmall buffering requirement
Capable of low latency chaining
WideTypically software based using NIC
Not linear raster related – frame basedLarger buffering required
Only capable of frame-delay-based chaining
N
W
W frame delivered in 95% of time
Ideal & observed W & N sender behaviour
30 October 2017
Frame period
N frame delivered in Active Picture time
Frame period
VBI
52 52
How many HD-SDI flows can you fit in 10GE?
SMPTE 2022-6/TR-04
1.485Gbps + RTP, UDP, IP, VLAN, MAC = ~ 1.65Gbps
10/1.65 = ~6?
SMPTE2110 Essence based 1080i50 = 1.0368 Gb/s
10/1.04 = ~ 9?
53 53
Post-raster timing & non-linear sources
0
2
4
6
8
10
12
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
bit rate
55 55
Data rates – HD-SDI 1080i50
1.485 Gbps
1.037 Gbps
1.141 Gbps
HD-SDI rate
Video essence rate * β
Video essence rate
β is the multiplier used on the video essence rate to create a ‘Committed Information Rate’
56 56
IP packets per video line *
HD-SDI 3 or 4 UHD 7 or 8
HS-SDI 3600 packets per video frame = 90,000 pkts/s
* Ethernet frames size and line-continuation dependant
59 59
Source bursting
NN-2N-3 N-1 NN-2 N-1N-3 NN-2 N-1N-3 NN-2 N-1
NN-1N-2N-3N-4N-5N-5N-6N-7N-8N-9NNN
60 60
Sender emission rate behaviour model
SENDER
Buffer modelwith max value
Buffer drains at β * essence rate
Importance of betaBeta is required for long-term bitrate fluctuations (e.g. VBI)
While beta cannot absorb short-term fluctuations, it allows for long-term bitrate excursions above the ideal rate.A gapped sender will start to overflow Cmax after ~60 video lines if beta is reduced to 1.0. This is due to the increased bitrate during the active frame.
Increasing sender burst sizeAn example of bursty sender behaviour: accumulate 32 packets, then burst
Once a burst from a sender exceeds Cmax, the Cfull buffer will drop packets.With a 10 Gbps line rate, a 24 packet buffer would be required to avoid loss following a 32 packet burst.
For Cmax = 9 and beta = 1.1, we get 47% packet loss as Cfull cannot drain packets in time.
65 65
Packet pacing on sender egress NIC
• NICs with hardware flow control
• NICs with no hardware flow control
• NICs shared by VMs
66 66
Policing/shaping in switches
• SHOULDN’T NEED TO DO THIS
• Switch policing has limited integration period flexibility
• Impossible to fully cross protect from rogue sender
• Harder at UHD rates
67 67
De-rating switch provisioning
• Necessary with W senders
• Switch-specific numbers
• Initial maths is pro-rata to the switch real buffering
• Restrict port loading in orchestrator to achieve required
control
68
VideoIPath – orchestration
Studio A
Studio B
IP Studio C
Processing Farm
Orchestration layer needs to also plan for sub-optimal senders!
IP media edge
PTP TIMING
DEVICEDISCOVERY & CTL
MEDIA FLOW IP ADDRESSING
ALTERNATIVE TIMING DOMAINS
RESTRICTED/PROXYDISCOVERY & CTL
DIFFERENT IP ADDRESSING (NAT)
ESSENCEFLOWS
ESSENCE ORCOMPOSITE FLOWS
PROTECTIONTERMINATION
PROTECTIONTERMINATION
Protection
n n+1 n+2
n+4 n+5 n+6
n+8 n+9 n+10
n+3
n+7
n+11
n+12 n+13 n+14
n+16 n+17 n+18
n+20 n+21 n+22
n+15
n+19
n+23
n+24 n+25 n+26 n+27
n+28 n+29 n+30 n+31
n+32 n+33 n+34 n+35
n+36 n+37 n+38 n+39
n+40 n+41 n+42 n+43
(1,1) (L,1)
(1,2)
(1,D) (L,D)
(2,1)
(2,2)
1 L2
flow A
flow B
SOURCE DESTINATION
flow A
flow B
DESTINATIONSOURCE
delay
Spatial
Spatial + temporal
FEC
72
Switch buffers handling flow non-linearity
buffe
rbuffe
rbuffe
r
aggregation
typically 10,000 packets buffering in total across switch ASIC?
1 video frame HD-SDI = 20ms (50P) = 3.7 MB = 2600 pkts
1ms @ HD 50P burst = 185KB = 130 pkts
1ms @ 4K100P burst = 30MB = 1040 pkts
73
Video packet sending profile
1.039Gbps
1.485Gbps
Startof‘frame’
Startof‘frame’
1080i50
Software sender – phase aligned?
Full network simulation – core & edges – essential to prove scalability & performance
75
Virtual Device n
Virtual Device n+1
Virtual Device n+2
Virtual Device n+3
Virtual Device n+4
Virtual Device n+5
Virtual Device n+6
Virtual Device n+7
Switch fabric requirement
Wire-speedNon-
blockingControl
Flow density
PTP support
Port density
Buffer memory
• Media node registration, discovery and control
• Network topology discovery and control
NMOS is work in progress
IS04/5/6
Datacentre Datacentre
studio
studio
Contribution / Servers
Studio Production
#4
Studio+Control MCB, Live Points, etc.
Studio 3, Control 1&2,
Studio A
Studio B, Operations Test Lab
MCR, Studio 1&2, Control
3&4, Post
Studio Production
#1
Studio Production
#2
Studio Production
#3
Contribution / Processing
Ingest / Video Servers
Playout / Distribution
IP WAN
VideoIPathmanagement and orchestration
88 88
Complete end to end linear IP workflow
Non real-time processing (with time stamping)
UDP flows on interconnect?!
Networking the moving picture II2nd November 2017 10am-4pm
London transport museum
nevion.com/news/events/network-moving-picture-2/
Recommended