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Bridging DVB and IP Networks with Optibase's MGW3100
Optibase White Paper
The contents of this publication may not be reproduced in any form by any means, in part or in whole, without the prior written permission of the publisher. The authors and publisher make no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for any particular purpose. Neither shall the authors or publisher be liable for any errors contained herein or for incidental or consequential damages in connection with the furnishing or use of this material. The information herein is subject to change without notice.
Introduction Deploying MGW 3100 in IP Networks Backhaul Video Contribution Video Distribution over IP MGW 3100 Benefits Success Stories Democratic National Convention MGW 3100 Product Overview Technical Specifications Download a PDF version of the MGW3100 white paper (PDF)
Introduction
The Internet has proved that IP-based transmission is one of the most efficient ways of transmitting data. Companies that have access to broadband private networks and leased lines are fast realizing that they can benefit from huge cost reductions by implementing IP multicast for video transmissions. One such sector is the broadcasting industry, which traditionally relies on expensive dedicated satellite links to convey video from one point to another. This white paper will explore how broadcasters can benefit from IP multicast in Backhaul, Video Contribution and Video Distribution solutions.
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Deploying MGW 3100 in IP Networks
Broadcasters traditionally use expensive dedicated satellite links for Backhaul, Video Contribution and Video Distribution applications. These applications involve transporting high-quality, high-bandwidth DVB ASI video between locations. Bit rates for transporting an MPTS (multi-program transport stream) can reach 120-150 Mbps and more. Satellite links have a fixed bandwidth of 27 or 38 Mbps per transponder. To transmit 120-150 Mbps stream, multiple transponders are needed. Often, this capacity is not fully utilized, resulting in unnecessary expenditure.
This section will discuss how Optibase's MGW 3100 can form a crucial bridge between IP and DVB networks, saving broadcasters costs in satellite links and allowing them to utilize alternative broadband infrastructures
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Backhaul
Backhaul refers to the distribution of high quality DVB MPEG-2 video from the central broadcasting station to regional broadcasting head-ends. For example, NBC will distribute footage to its regional stations which deliver it to consumers' homes.
Backhaul Application Using Satellite
Backhaul Application Using IP
In the above example we can see that no matter what the bit rate of the streams being transported, the broadcaster will always pay for 27 or 38 Mbps per transponder of bandwidth when using a satellite link to transport the video from the central broadcasting headquarters to the regional head-end. Sometime, multiple transponders are needed. Broadcasters who have access to broadband IP networks can use Optibase's MGW 3100 Transmitter to convert the incoming MPEG DVB ASI stream to IP. The MGW 3100 encapsulates the incoming MPTS stream in IP format by using RTP or UDP protocol. The IP stream is then assigned a multicast IP address and transmitted over the broadcaster's IP network to regional head-ends. At each regional head-end, an MGW 3100 Receiver receives the IP stream and extracts it back to DVB ASI stream for the local application.
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Video Contribution
Video Contribution refers to transferring video footage that is filmed on location to the central broadcasting station for editing. For example, news footage is transferred from the field to the central broadcasting station where it is edited. In this application, Optibase's MGW 3100 takes the filmed video, which can be either an SPTS or MPTS stream and sends it over IP, in unicast mode, to the central broadcasting station for editing.
Video Contribution using Satellite
Video Contribution using IP
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Video Distribution over IP
Video distribution is another application where broadband service providers (BSPs) and operators can benefit from video over IP. BSPs have an interest in generating additional revenue by offering enhanced services to their subscribers. Enhanced services include digital TV, interactive TV, video-on-demand (VOD), time-shifted TV and personal video recording capabilities. Much of the content that BSPs have access to is available in MPEG-2 DVB ASI format. This video content has to be converted into IP data in order for it to be delivered over the BSP's IP network to subscribers' homes. To meet this requirement, MGW 3100 receives the DVB ASI multi-program transport stream, demultiplexes it, and encapsulates each program in a separate IP multicast stream. MGW 3100 also performs VBR (variable bit-rate) to CBR (constant bit-rate) conversion so that the IP STB and desktop multicast clients at the receiving end can play back the streams correctly.
In the race to be the first to provide enhanced services and gain market share, many cable operators have also deployed IP networks. Like BSPs, they use the MGW 3100 to convert DVB ASI streams into IP for distribution over their IP networks to subscribers' homes.
Video Contribution using Satellite
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MGW 3100 Benefits
The MGW 3100 offers numerous benefits to broadcasters and operators who want to implement IP transmission.
Cost Savings
By switching to IP based transmission instead of satellite, broadcasters can save on expensive satellite lines.
Efficient Bandwidth Management
IP networks allow broadcasters and operators to manage bandwidth in a far more efficient way. Bandwidth capacity corresponds to the bit rate of the streams being transmitted. In contrast, satellite links have a fixed capacity of 27 or 38 Mbps per transponder.
Open Standards Solution
MGW 3100 conforms to DVB-ASI, SNMP, IGMP, QoS and RTP. It also supports established digital video and IP networking standards, ensuring that it will integrate smoothly and efficiently with other networking and broadcasting equipment.
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Success Stories
Democratic National Convention
Slingshot Networks, the Official Webcast Producer for the Democratic National Convention (DNC), used the MGW 3100 to transfer daily broadcast feeds from Staples Arena in Los Angeles to their webcasting and broadcast uplink facility in Nashville, Tennessee. In Los Angeles, Slingshot used a broadcast encoder to encode the video feed into a 25 megabit per second "contribution" quality MPEG-2 digital video signal. MGW 3100 encapsulated the compressed video into IP packets and streamed the data over the Qwest broadband network. This IP stream was received at Slingshot Networks in Nashville, Tennessee, where another MGW 3100 regenerated the broadcast video feed for Slingshot Networks digital media creation, storage and distribution system.
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MGW 3100 Product Overview
MGW 3100 is a video- over- IP rack- mount system that bridges digital video and high- speed data networks. MGW 3100 creates new opportunities for service providers by serving as a media gateway between DVB and IP networks. MGW 3100 is ideal for applications such as Backhaul video over IP networks or bridging DVB and IP interfaces at head-end installations. For IP head-ends, MGW 3100 enables the re-distribution of received
MPEG-2 DVB streams onto IP based networks.
In transport mode operation, an MGW 3100 receives MPEG-2 DVB-ASI streams (SPTS or MPTS), encapsulates the streams (SPTS or MPTS) in IP using the RTP or UDP standard, and transmits them over the network. At the receiving end, an MGW 3100 receives the MPEG-2 /IP stream, extracts it, and plays it back as a DVB-ASI stream. Alternatively, in demux mode operation, an MGW 3100 receives a DVB ASI MPTS stream, demultiplexes the stream and encapsulates each program into a separated IP multicast stream and transmits them over the IP network. An IP based set- top- box or a desktop decoder supporting IP multicast can receive and play back the stream. By combining RTP transmission, Diffserv QoS support and a Linux based operating system, MGW 3100 ensures efficient and reliable transmission over IP networks.
MGW 3100's Remote Session Manager allows you to control unicast and multicast transmissions from one MGW 3100 system to single or multiple MGW 3100 receiving systems. The Remote Session Manager can communicate with one transmitter and up to 20 receivers simultaneously and allows configuration, operation and on- going monitoring of the transmission.
Features
MPEG-2 DVB- ASI to MPEG-2 over IP
End to End solution - DVB to IP, and IP to DVB conversion
Standard RTP encapsulation
IP unicast and multicast
Remote session management
QoS through Diffserv
Rack- mounted, Linux based server
PID Filtering
RTSP session signaling
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Technical Specifications
System
Physical
Dimensions: 1RU form factor; 1.65 x 16.75 x 25", 4.19 x 42.55 x 63.5 cm (HxWxD)
Weight: 28.6 lbs, 13 kg Scalability: Upgradeable to dual processors; Memory upgradeable to 4 Gb
Electrical Characteristics
Maximum Power consumption: 190 W (peak) Operating line frequency: 60 Hz
Input/ Output Interfaces
100 BaseT Gigabit Ethernet (option)
Environmental
Operating temperature: 50- 95 F, 10- 35 C
Storage temperature: -22- 122 F, -30- 50 C
EMC standards (pending): CE Class B, FCC Class A, CSA Class- A
Safety Standards
CE- LVD (pending)
Management
Client/ Sever based Session Manager
Network Protocols
UDP Multicast and Unicast
RTP-RFC 1889
TCP/ IP
RTSP - RFC 2326
Modules
Available Hardware Interfaces
DVB- ASI (Other hardware interfaces available by special order.)
DVB- LVDS
DHEI
RS-422 Parallel
RS-422 Serial
M2S
M2P
SMPTE 310MF, SIF
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