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Low Cost Live Backhaul Over the Public Internet

White Paper

How broadcasters are reducing operational costs by transporting live, HD video over low-cost internet connections

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

Introduction

It is estimated that by 2019 video will represent 80 percent of the world’s internet traffic. While a lot of that traffic is on-demand consumption, a growing percentage is also live video. Gone are the days when consumer technology and internet connections supporting video consumption lack global accessibility. Today’s broadcasters are faced with what seems to be an insurmountable challenge: how to quench their audience’s thirst for more content without significantly increasing operational costs.

As video is being sourced from locations around the world to meet this demand, it’s becoming obvious that traditional methods of live video transport like satellite and MPLS networks take time to provision and lack the flexibility and cost structure to solve the challenge on its own. In recent years, broadcasters have looked to low-cost, readily available internet connections to help transport more secure, low-latency, HD video for remote interviews, remote production and broadcast affiliate distribution.

This white paper explores the viability of using low-cost, readily available internet connections for live video transport and the technologies that make it possible, helping broadcasters fill their audience’s insatiable need for more content.

REQUIREMENTS FOR LIVE BACKHAUL CONTRIBUTION:

• High picture quality• Low latency (<<500ms)• 24-7 operation• HD-SDI in/out

Ubiquity of network connections and screens is creating a never ending opportunity to deliver live and on-demand content to audiences. This influx of demand is encouraging broadcasters to explore alternatives to expensive satellite links and MPLS networks for live video transport.

Broadcasters are looking for solutions that can:

• Quickly provision remote feeds for news and events contribution• Reduce the overall cost of travel expenses and additional man-power with support for remote production• Eliminate the cost of satellite and dedicated networks for remote feeds• Monitor remote operations and productions

Broadcasters have always relied on dedicated networks and satellite for live remote content contribution. These solutions provide reliability in regards to connection state and quality, but tend to be extremely expensive. The cost of dedicated networks and satellite are coming down slowly over time, but are not decreasing nearly as fast as the increasing demand for live content. In addition to exorbitant operating costs, these solutions take a long time to provision, are difficult to schedule and do not offer the flexibility needed for today’s applications.

True Cost of Satellite Is the Delay Broadcasters are looking for new ways to engage their audience by bringing in more remote live interviews with industry experts and personalities who often need to conduct the interviews from homes, offices and remote studios. With this type of agile, live programming, it is imperative for broadcasters to create a cohesive viewing experience with fluid, real-time interaction.

Although satellite can provide reliability and quality for these types of interviews – at a significant cost – is it really “live”?

Satellite typically provides a latency of 2 seconds, above the backhaul contribution requirement of less than 500 milliseconds. This latency has always been accommodated by training the remote participant to use and react to audio cues in order to minimize the visual awkwardness caused by the delay.

The Cost of Traditional Transport Methods for Live Backhaul

Growing Demand for Video Transport

• Connect facilities with live video to increase workflow efficiencies• Provide return feeds to remote talent for production context and interactive interviews

The evolution of digital distribution has led broadcasters to the internet as an equally performing solution for live video transport, meeting their “new world” requirements at a fraction of the cost.

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

VIDEO TRANSPORT COMPARISON CHART

MPLS

SATELLITE

~150+/hr, $3k-5k/day truckDifficult to schedule

Need to provide downlinkHigh latency

DEDICATED NETWORK

~1,5k-5k/6Mbps/monthAdditional CPE devices

Long lead time [30 - 90 days]Annual contract

High latency

SERVER ASSISTED

$1k per endpoint$130/Mbps/month

Multiple vendorsAnnual contact

Interviewing with satellite has the potential to disrupt the flow of programming.

For instance, a financial industry expert commenting on an event as it relates to the stock market will more often than not forgo preparation and training. Add in additional remote participants and anything over 500 milliseconds of latency becomes an awkward viewing experience for your audience.

As the need for this type of content grows, broadcasters are seeking better technologies that can enable the most immediate and fluid remote interactions with everyday, untrained people.

HOW PACKET LOSS AFFECTS VIDEO QUALITY

I Frame: Missing data in the I-frame [KeyFrame] will affect the entire image and sequence

P Frame: Missing data in the P-Frame will affect the rest of the sequence

B Frame: Missing data in the B-Frame affects the frame only

In recent years, broadcasters have looked to the internet as a potential means to quickly provision multiple remote feeds for live news and events contribution, interactive interviews and affiliate distribution. Although the internet has proven to be moderately successful at accommodating file transfer and high quality media streaming, it is wrought with challenges when transporting live, HD video.

Is the Internet Ready for Live Backhaul?

<0.001% Over an MPLS network

<0.1% In a building

<0.5% Across a campus

~1% Over the internet [stable network]

~5% Over the internet [unpredictable network]

PACKET LOSS YOU SHOULD PLAN FOR

PUBLIC NETWORK OBSTACLES

Packet Loss Packets being discarded by routers

Jitter Packets arriving at different times than expected and sometimes out of order

Latency Time from sender to receiver

Bandwidth The fluctuating capacity between points

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

Packet loss, jitter, latency and the fluctuation of bandwidth are challenges that need to be overcome when attempting to transport live video over the internet. Packet loss is a particularly important problem when transporting compressed video, as its effect to the end product can be extreme.

When video is faced with network congestion, the network has no other option than to drop packets as the video passes through. If only one packet of information disappears, it can affect a single block of video in a frame, the entire frame of video or the entire sequence of video, and can impact the audio. Over the internet, network speeds and congestion are unpredictable, and viewers can go from fluid real-time video to a frozen image in less than a second.

FORWARD ERROR CORRECTION OVERHEAD

IP OVERHEAD -20% to 30%

COMPRESSED AUDIO 64 to 256 kbps

COMPRESSED VIDEO 300kbps to 20Mbps

FEC OVERHEAD -15% to 25%

TOTAL BANDWIDTH

Forward Error Correction (FEC)FEC rebuilds missing packets by reverse calculating redundant information sent with the base data (similar to RAID hard drive technology). When the information is about to leave a source encoder, redundant information is calculated and added to the stream to allow for the reverse recovery calculation to be performed should a packet go missing. FEC does incur a bandwidth overhead related to how resilient the stream needs to be (typically less than 20 percent).

FEC will introduce additional delay - the time needed to build the redundant information and to confirm all expected data (packets) have been received or rebuilt (typically 15-60 milliseconds for a good implementation). FEC is known for its performance with more predictable networks that have less packet loss, like a secure campus network or a satellite connection for example. It works well in one-way networks and with multicast networks (one-to-many distribution).

The benefits of FEC become limited when several consecutive packets are lost, which is typical of IP network congestion. FEC works better when packet loss is distributed evenly. However, when faced with more unpredictable networks, such as the public internet, where packet loss can be dramatic, FEC is ineffective and your stream will break apart.

Packet RetransmissionPacket retransmission is the basis of TCP/IP, a protocol used in almost all internet transmission of information (files, web pages, etc.). TCP/IP assigns a number to every packet sent. The sender holds onto a copy of the packet until the receiver acknowledges that it has received the packet. If no acknowledgement is received within a certain time, the sender resends the packet. Packet retransmission requires a level of patience. Send, receive, acknowledge, send back, wait, send back, resend, re-acknowledge. Although this solution is effective for non-time-sensitive video transmission, it lacks the speed to be used in low latency applications.

Although transporting high quality, live video over the internet is challenging, using today’s protocols and technologies, it is possible. Focusing on some of the most widely used protocols and technologies, we’ll explore the advantages and disadvantages of each technology as it relates to transporting low latency, secure, HD video over the internet.

Fragmented StreamingFragmented streaming, more commonly known as segmented streaming, is one of the most commonly used technologies to transport video over the internet, slicing video content into 1-10 second file segments. When the video reaches its destination, the video files play sequentially with no visible break. Although this method is effective, it takes time. The stream needs to be encoded, captured into a segmented file, sent over the network and finally collected into a buffer before reaching its end point. One 3 second file segment can compound into 30 seconds or more of overall delay before being played at the destination.

Transporting Low Latency Live Video Over the Internet

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

Although some of today’s used protocols and technologies facilitate the transport of live video over readily available, low-cost internet connections, most lack the ability to meet broadcasters’ requirements for live backhaul contribution.

Haivision, an enterprise video company with decades of experience in video streaming and networking, has developed technology that helps broadcasters make low-cost, readily available internet connections secure and reliable for low latency, HD video transport.

How SRT WorksHaivision’s SRT (Secure Reliable Transport) brings together best in class protocols and proprietary technologies like encryption, packet loss recovery, and network awareness so that video and other traffic can cross unqualified networks (like the public Internet) and firewalls.

SRT combines industry-standard encryption with proprietary packet loss recovery and network awareness to insure that your video content stays pristine regardless of network conditions.

Haivision’s SRT offers significant operational flexibility and cost savings over, or compared to, satellite and custom network infrastructures. SRT allows broadcasters to quickly provision remote feeds over low cost networks for live news and events contribution, interactive interviews and affiliate distribution.

SRT is applied to contribution and distribution endpoints as part of a video streaming workflow. After encoding, AES 128/256 encryption is applied to SRT and provides error recovery. Prior to decoding, SRT decrypts the stream and recovers from packet loss typical of Internet connections.

SRT also monitors the network conditions between the encode and decode endpoints. It gives users the necessary flexibility to accommodate different deployment requirements and network conditions by adjusting the quality and the latency of the transmission. Users can tune their streams ensuring that bandwidth is not oversubscribed, jitter is accommodated, and latency impacts are understood.

IT FriendlyAs you’re planning your live backhaul workflow, you also need to consider your firewall – a potential barrier to receiving low latency video. Firewalls are meant to block unauthorized/unsolicited external traffic. They do typically allow internal traffic and requests to go out and will allow corresponding responses to get in from the outside.

As a broadcaster supporting newsgathering or remote production, you are likely trying to send a stream from a remote, unpredictable location. Unless the event is planned with advanced notice, it is very difficult to get the appropriate support from the IT department of the event location to set firewall rules and other network-related activities required for your stream. Without a tool to manage firewall traversal, establishing links between endpoints can prove to be more challenging than you would think.

SRT has a number of key features that make it a better choice for video transport over the internet.

Media AgnosticSRT is audio/video format agnostic, meaning it can transport any type of codec, resolution or frame rate. This is important because it can future proof your workflows by working transparently with MPEG-2, H.264 and HEVC as examples. It also transmits audio and metadata synchronized with your video, which makes it ideal for most data-heavy applications found in enterprise and government environments.

Transport Low Latency VideoSRT is fast. Its latency is configurable to accommodate a user’s deployment conditions. Leveraging proprietary real-time IP communications development to extend traditional network error recovery practices, SRT delivers media with a fraction of the latency introduced by TCP/IP, while offering speed without the disadvantage of standard UDP transmission.

End-to-End Video WorkflowSRT is a compact, self-contained library with optimized processing and memory footprint, allowing for ease of integration into a variety of applications running on a range of platforms from embedded systems to cloud solutions.

SRT is integrated across Haivision’s technologies – from encoders, through gateways, transcoders, and media management systems, and to our decoders, set-top boxes, soft players, and mobile applications. This helps avoid the frustration of dealing with multiple vendors.

SRT Features and Benefits

A Smarter Solution

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

For Haivision’s customers, delivering video from one point to the next is just part of a complete end-to-end media ecosystem.

Straight-Forward PricingSRT is included for free within the Haivision ecosystem of solutions. All our products have permanent licenses and, unlike other solutions, Haivision does not charge endpoint license fees, recurring fees or offer complicated quoting, pricing, or proposal processes. We make pricing even easier with pay-as-you-go cloud instances.

Firewall Traversal Made EasyProvisioning multiple streams across unknown networks can be a challenge. This is exemplified when trying to get a stream out from a remote event and attempting to traverse the location’s unknown firewall. With flexibility to accommodate different network configuration scenarios, SRT is firewall friendly. An encoder can call the decoder, the decoder can call the encoder and both can “meet” on the network, thus providing the flexibility to minimize IT intervention.

Gone are the days when “cost-effective” meant sacrificing quality. The evolution of digital distribution and its supporting technologies have paved the way for Haivision to develop a true alternative to traditional methods of live video distribution.

Integrated across Haivision’s products and provided at no additional charge, SRT provides broadcasters with a high performing, scalable and cost-effective solution for live backhaul over any network.

Haivision’s SRT and video streaming solutions have allowed broadcasters to re-imagine their live backhaul infrastructures.

From aggregating SRT streams over the internet from multiple remote production venues with the Haivision Media Gateway, or delivering low latency, secure, HD video streams with Haivision’s award winning Makito X encoder and decoder, broadcasters now have a better way to deliver more content without significantly increasing operational costs.

That’s a Wrap

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GenericEncoder

WITHOUT SRT

Makito XDecoder

Makito XEncoder

WITH SRT

SRT SRT

WHITE PAPER | LOW COST LIVE BACKHAUL OVER THE PUBLIC INTERNET

Need a handplanning your live backhaul workflow?

We can help.Contact our broadcast video experts to learn more.

North America: 1.877.224.5445

International: +1.514.334.5445

Haivision, a private company founded in 2004, provides media management and video streaming solutions that help the world’s leading organizations communicate, collaborate and educate. Haivision is recognized as one of the most influential companies in video by Streaming Media and one of the fastest growing companies by Deloitte’s Technology Fast 500. Haivision is headquartered in Montreal and Chicago, with regional offices located throughout the United States, Europe, Asia and South America. Learn more at haivision.com.