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The IP Revolution. The IP Revolution. IP Revolution Why now? The 3 Pillars of the IP Revolution How IP changes everything. IP Revolution. This is really a misnomer What we are in the middle of is a Digital revolution The CCTV world is moving from Analog to Digital
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The IP Revolution • IP Revolution • Why now? • The 3 Pillars of the IP Revolution • How IP changes everything
IP Revolution • This is really a misnomer • What we are in the middle of is a Digital revolution • The CCTV world is moving from Analog to Digital • This is much more than just the transmission (IP)
What Digital means • Why have so many technologies gone digital? • Digital signals do not degrade with distance • Digital data does not degrade with time • Digital data does not degrade when copied • Incredible digital technologies can be used for IP Video • Simple concepts with huge implications
Why Now? • The technologies required have come together at exactly the same time • All the required technologies are now at price points which make IP system cheaper than analog ones
3 Pillars of the Revolution • Compression • Networks • Storage
Pillar 1: Compression • Raw PAL/NTSC video runs at 158 Mbps • This needs to be compressed! • This will get worse with HD • 720p HD Video is 500 Mbps • 1080p HD Video is 1,000 Mbps!
CCTV and TV • Compression for TV is different • In the TV world there are millions of decoders for every encoder • In CCTV it is the other way around • CCTV needs low latency • So a good compression standard for TV is not good for CCTV
Compression Tools • MJPEG – simple to implement but not good • MPEG-4 – more difficult to implement, but good compression • H.264 (now MPEG4 part 10) difficult to implement and excellent compression
What bitrate? • Assuming a Good H.264 compressor: • Standard PAL/NTSC: 2 Mbps • 720p HD: 1 – 6 Mbps • 1080p HD: 2 – 10 Mbps • A bad compressor will 10x these values – and your storage will be 10x!
Pillar 2: Networks • Ethernet Switching has revolutionised networking • In a switch data is only transmitted on the ports where the data is sent to • The ‘Backbone’ of the switch can handle much more than the speed of each port
Example 24 port switch • Cisco 2960 • 24 x 100Mbps ports • 2 x 1 Gbps ports • Switching capacity 6.5 M Packets/sec • With 1 Kbit packets this is 6.5 G bps • That is 3000 streams of 2Mbps video! • 400 Pounds
Rack encoders • Rack based encoders reduce costs even further – as long as they have 1 Ethernet connection • 20 racks connected to a switch with 10 slots per rack gives 200 streams • At $800 per switch that is $4 per stream!
Spreading the load • Distributing the recording around the network means that very large systems can be built easily • For a 2000 camera system you do not just multiply the bandwidth by the number of streams • More details this afternoon
Long distance • If you can lay fibre the cost per stream is very low • Wireless technology has dropped in price • WAN networking costs are dropping and available bandwidths are climbing
Choosing switches • Make sure the whole network is thought out and designed • Check features like the maximum number of multicast groups • Always buy managed switches • Don’t scrimp – but don’t over engineer!
Power Over Ethernet • This technology has always been good • The price per slot is now very low • The PoE premium is around £7 per port • Compared to the cost of cabling and individual power supplies this is a huge saving • A new standard will provide enough power for PTZ!
Pillar 3: Storage • Storage can be as much as 50% of the total system cost • Disks just keep getting bigger (now 1.5TB) • End users want to record: • Higher quality • Higher frame rates • For longer • HD Cameras demand even more storage!
Video Storage is not normal • CCTV puts very high demands on storage • Data rates are very high and relentless • The read/write ratio is completely different to a general office environment • CCTV is 99.9% write 0.1% read
Not all disks are the same! • All disk manufacturers have disks with different ratings • Make sure the disks in your NVR are rated for 24/7/365 operation
Why IP Changes Everything • Distance does not matter • Easy scalability • Software decode – workstation based security • Analog: cheap input - expensive output • Digital: cheap input - free output • Composite video is dead
Distance does not matter • In an analog system distance is everything • In a digital world a camera on a network is on the network – regardless of distance • A camera 100ft away is the same as one 10 miles away • An NVR 100ft away is the same as one 100 miles away
Easy Scalability • Modern networks have capacity to handle many thousands of streams • Modern workstations can decode many streams of video • As long as the software supports large numbers scalability is easy
Software Decode • Viewing video does not need custom equipment • Viewing video does not need hardware help • Decoding video is much easier than encoding it
Analog - Digital • When IP video is compressed – the hard bit is done • Taking a video stream off of the network and displaying it just needs a PC based workstation • In the digital world viewing is cheap
Summary 3 Pillars of the Revolution • Compression • Networks • Storage