SIN 511 Issue 1.9 November 2016

Transcription

1 SIN 511 Issue 1.9 November 2016 Suppliers Information Note For The BT Network BT Wholesale TV Connect (TVC) Service & Interface Description Each SIN is the copyright of British Telecommunications plc. Reproduction of the SIN is permitted only in its entirety, to disseminate information on the BT Network within your organisation. You must not edit or amend any SIN or reproduce extracts. You must not remove BT trademarks, notices, headings or copyright markings. This document does not form a part of any contract with BT customers or suppliers. Users of this document should not rely solely on the information in this document, but should carry out their own tests to satisfy themselves that terminal equipment will work with the BT network. BT reserves the right to amend or replace any or all of the information in this document. BT shall have no liability in contract, tort or otherwise for any loss or damage, howsoever arising from use of, or reliance upon, the information in this document by any person. Due to technological limitations, a very small percentage of customer interfaces may not comply with some of the individual characteristics, which may be defined in this document. Publication of this Suppliers Information Note does not give or imply any licence to any intellectual property rights belonging to British Telecommunications plc or others. It is your sole responsibility to obtain any licences, permissions or consents which may be necessary if you choose to act on the information supplied in the SIN. Those BT services marked indicates it is a registered trade mark of British Telecommunications plc. Those BT services marked indicates it is a trade mark of British Telecommunications plc. This SIN is available in Portable Document Format (pdf) from: Enquiries relating to this document should be directed to: help@sinet.bt.com British Telecommunications plc Registered Office 81 Newgate Street LONDON EC1A 7AJ Registered in England no

2 CONTENTS 1. INTRODUCTION SERVICE OUTLINE ARCHITECTURE Content delivery to TV Connect Headend ISP Chooses to provide uncompressed content; TV Connect to encode and condition TV Connect Protect ISP Chooses to provide compressed content; ISP to encode and condition Multicast Content Distribution Home Environment/End User Experience ISP SERVICES TV CONNECT INFRASTRUCTURE DESCRIPTION Overview End-To-End Service Flow Example (Fibre access, FTTC and FTTP via Openreach GEA) End-To-End Service Flow Example (Copper access from an MSAN) BT WHOLESALE HOSTED TV ENCODING HEAD END CHANNEL INGRESS TO TV CONNECT HEAD END INGRESS OF STANDARD DEFINITION VIDEO SDI General Video Audio Main Programme Audio Description Broadcaster Mix (AD-BM) Audio Description Set Top Box Mix (AD-STBM) Subtitles INGRESS OF HIGH DEFINITION CHANNELS - HD-SDI General Video Audio Main Programme Audio Description Broadcaster Mix (AD-BM) Audio Description Set Top Box Mix (AD-STBM) Subtitles INGRESS OF ULTRA HIGH DEFINITION CHANNELS - UHD-SDI General Signal Compliance Video Each Quadrant Video - Combined Quadrants Audio Main Programme Audio Description Broadcaster Mix (AD-BM) Audio Description Set Top Box Mix (AD-STBM) Use of AD- STBM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo or surround sound). Subtitles CONTENT DELIVERY PACKAGING ENCRYPTION FORWARD ERROR CORRECTION SDI CHANNEL EGRESS FROM TV CONNECT HEAD END SECURING ACCESS TO CONTENT Overview Conditional Access Interfaces between TVC Head End and ISP CA/Encryption device Ports and Addressing Entitlement Management Messages (EMM) Update/Announce ISP MULTICAST INGESTION INTO TVC CHANNEL INGRESS TO TV CONNECT HEAD END SUMMARY OF POTENTIAL CONTENT ROUTEING AND PROCESSING HEADEND OPTIONS SIN 511 Issue 1.9 British Telecommunications plc Page 2 of 33

3 6. IP MULTICAST STREAMS MAXIMUM BANDWIDTH CHANNEL AGGREGATION MULTICAST SOURCE AND GROUP IP ADDRESSES RETRANSMISSION TV CONNECT CUSTOMER PREMISES EQUIPMENT (CPE) IGMP REQUIREMENTS MESSAGE SEQUENCING SET TOP BOX (STB) FUNCTIONS RESIDENTIAL GATEWAY (HOME ROUTER) FUNCTIONS [5] SERVICE AVAILABILITY ISP RESPONSIBILITIES REFERENCES ABBREVIATIONS HISTORY FIGURES FIGURE 1 BT TV CONNECT SERVICE ARCHITECTURE 5 FIGURE 2 ISP CONNECTIVITY OPTIONS 7 FIGURE 3 OVERVIEW OF NETWORK INFRASTRUCTURE 9 FIGURE 4 END TO END FLOWS FOR AN END USER CONNECTED VIA FIBRE, FTTC AND FTTP VIA OPENREACH GEA 10 FIGURE 5 END TO END FLOWS FOR AN END USER WITH COPPER ACCESS CONNECTED TO AN MSAN 11 FIGURE 6 ISP CONDITIONAL ACCESS SUPPORT 20 FIGURE 7 TVC HE ENCODING 22 FIGURE 8 TVC SDI EGRESS 23 FIGURE 9 TVC SDI EGRESS TO ISP ENCODING PLATFORM 23 FIGURE 10 TVC MULTICAST INGEST ONLY 23 FIGURE 11 TV CONNECT IGMP FLOWS 25 SIN 511 Issue 1.9 British Telecommunications plc Page 3 of 33

4 1. Introduction This Supplier s Information Note (SIN) 511 provides service description information for customers of the BT Wholesale TV Connect (TVC) family of products. TVC delivers broadcast quality TV over BT Wholesale s dedicated broadband network. TVC enables ISPs to deliver reliable and cost effective TV services to their end users across the breadth of the BT 21CN broadband network making TV Connect a viable alternative to traditional Satellite and DTT signal transmission. This coverage is achieved through our state of the art, multicast enabled IP based network. It should be noted that the information contained within this SIN might be subject to change due to either the results of BT testing or feedback from trial participants. Please check with the site to ensure you have the latest version of this document. Numbers in square brackets [ ] denote further references, as listed in Section 10. Further information about the commercial aspects of TV Connect can be obtained by contacting your Account Manager or Customer Relationship Manager. SIN 511 Issue 1.9 British Telecommunications plc Page 4 of 33

5 2. Service Outline 2.1 Architecture Commercial relationship ISP Encoding and/or Encryption TV Content (Content Provider) TV Copper & Fibre access For WBC STB 21C TVC Head End FacilityLine Plus Residential Gateway Openreach BRAS/LAC 21C Interconnect ISP RET Multicast TV channels path Unicast WBC data path TV Connect Interface ISP Figure 1 BT TV Connect Service Architecture The TV Connect Service Architecture is indicated in Figure 1. The TV Connect service is built on top of the underlying Wholesale Broadband Connect (WBC) service. An ISP planning to purchase the TV Connect (TVC) service will utilise the WBC PTA or L2TP handover service. The TV Connect service will multicast live streaming TV Channels from ingress in the TV Connect Head End to end users on the WBC platform Content delivery to TV Connect Headend The ISP will be expected to provide TV content to the Head End, often in conjunction with a content provider subject to a commercial relationship. The ISP will be expected to deliver content to the TV Connect Headend either as uncompressed (SDI or HD/SDI) content or as compressed (encoded IP multicast) content. The ISP would provide uncompressed content if they are opting for TV Connect to encode and condition the content ready for multicast distribution. The ISP would provide compressed content if they are opting to encode and condition the content ready for multicast distribution themselves. SIN 511 Issue 1.9 British Telecommunications plc Page 5 of 33

6 2.1.2 ISP Chooses to provide uncompressed content; TV Connect to encode and condition If content is uncompressed, the ISP is expected to provide two separate feeds per channel of content to the Head End. SD and HD TV content is expected to be delivered to the Head End via FacilityLine Plus. UHD TV Content is expected to be delivered to the Head End via the Openreach Broadcast Access Product 3Gb HD-SDI Quad Unidirectional. Note: The ISP may use connectivity methods other than a Facility Line or FacilityLine Plus. The ISP must advise BT of its intended connectivity method prior to order placement. Each method will be assessed by BT on a case by case basis and BT will advise the ISP if the method requested can be supported or not. The TV Connect service will encode and condition live TV content within the TV Connect Head End for onward multicast distribution across the BT 21C network. The ISP will be responsible for the encryption of their TV channels for conditional access by end users TV Connect Protect BT Wholesale introduced an additional resilience option for the TV Connect service in early 2014, applicable where the ISP presents uncompressed content. ISPs can benefit from additional resilience capabilities by choosing this chargeable option. Channel protection will be available for a limited number of channels via an alternative Head end as specified on the CRF by the ISP. The alternative Head End will function in a very similar manner to the main Head End with similar interfaces for channel ingress and conditional access. The ISP is expected to provide additional connections to the alternative Head End for the channels to be protected, separately from the TV Connect product ISP Chooses to provide compressed content; ISP to encode and condition If compressed, the ISP is expected to provide aggregated multi channel content to the Head End via the TVC Multicast Ingest Point (MIP) using 1Gb electrical links. The TVC MIP offers a Geo-Resilient option whereby the ISP may additionally present their content at the second (Geo-Resilient) site. Figure 2 below illustrates the three options available wherein: o ISP A connects via 2 links to each site (one to each landing point at each site). o ISP B connects via 1 link to each site (one to the primary landing point at each site). o ISP C connects via 2 links to only the main site, BT Tower (one to each landing point at BT Tower). Each of the options clearly offer different levels of physical or geographic resilience. Note that the option to connect exclusively at the secondary site is not offered. SIN 511 Issue 1.9 British Telecommunications plc Page 6 of 33

7 BT Tower (Main Headend Site) TVC MIP SAS X TVC HER X ISP B ISP C ISP A TVC MIP SAS Y TVC HER Y MAR 1 21C Distribution BT Colombo (Secondary Headend Site) MAR 2 TVC MIP SAS X TVC HER X TVC MIP SAS Y TVC HER Y Figure 2 ISP Connectivity Options The ISP will be responsible for the encryption of their TV channels for conditional access by end users Multicast Content Distribution The TV Connect traffic will be delivered across the end to end network over a separate logical path from the WBC data traffic. (See Section below) The ISP may choose to provide its own Retransmission (RET) solution for packet repair. A feed of the full multiplex of their channels may be supplied by BT Wholesale to support such a solution. Details of handover points will be agreed during contract negotiation subject to a successful development and test programme with the ISP. The ISP will be responsible for interconnection to their own equipment from the agreed handover points. The ISP may forward retransmission repair and control traffic via the WBC service Home Environment/End User Experience The end user access link may be via WBC fibre or copper as provided by Openreach. The ISP will be expected to provide the required equipment (e.g. a Residential Gateway (home router) and set top box (STB) or other equipment) to an end user in order to support the live streaming of TV channels. The ISP will be responsible for end user packages, end user repair and end user billing. BT Wholesale will provide interfaces to support provision, repair, service monitoring and billing. 2.2 ISP Services The TV Connect product is an optional feature of the WBC service that allows live streamed content to be delivered to End Users from a Head End within the BT Wholesale network. SIN 511 Issue 1.9 British Telecommunications plc Page 7 of 33

8 The WBC SIN is available from TVC Service Configuration An ISP will buy TV Connect from BT Wholesale to deliver channels to its WBC broadband end users. BT Wholesale takes on the delivery of TV channels to all the WBC end users as part of the product. Only a WBC customer (ISP) can take up the TV Connect service. The TV Connect service is available to ISPs that take the WBC PTA (PPP termination and aggregation service) and the WBC L2TP (Layer 2 Tunnelling Protocol) handover service. The ISP will supply TV channel content to the BT Wholesale TV Connect Head End. The ISP will be responsible for the Residential Gateway (home router) and set top box (STB) functionality within the end user s environment. It is the responsibility of the ISP to provide any TV Channel restrictions to individual WBC broadband end users it deems necessary. For all requests to provide channel capacity within the current network capacity (as agreed and managed with BT Wholesale) available on the TV Connect network, BT Wholesale will deliver channel capacity to an ISP s end users who are on WBC fibre and copper, in line with forecasted channel demand from the ISP following the process as set out in the TV Connect Product Handbook. Where there is a need to provide additional channel capacity beyond the current network capacity available, the ISP can submit a request by contacting their account team who will raise a request in to the TV Connect Product Line via the Statement of Requirements (SoR) process. An assessment of such a request will then be carried out to determine if the demand for additional capacity can be accommodated in line with the SoR process timelines. An ISP can check the availability of Multicast at WBC exchanges by using the Broadband Availability Checker available at via the Routing and Planning section under the Applications tab. When the ISP is ready to raise an order to provide/add channels, all of the channel details - including whether or not the channel/s are required on both fibre and copper networks - must be clearly marked in the appropriate fields on the TV Connect CRF. 2.3 TV Connect Infrastructure Description Overview An overview of the network infrastructure that supports TV Connect is illustrated in Figure 3. SIN 511 Issue 1.9 British Telecommunications plc Page 8 of 33

9 ISP Encryption/Encoding Openreach SMPF Compressed, Encrypted TV Content In STB Residential Gateway MSAN EEA EEA MAR MAR 4 x EAD MIP BT Tower (Main HE Site) Uncompressed TV Content In FTTP 21C Core 4 x EAD MIP Uncompressed TV Content In PON L2S EES BRAS/LAC BEA Bt Colombo (Secondary Site) BT Wholesale DSLAM Openreach Cablelink FTTC Openreach GEA Broadband ISP MSIL ISP N/W MSIL ISP N/W LNS FacilityLine Plus Or Openreach Broadcast Access Product 3Gb Figure 3 Overview of Network Infrastructure The TV Connect service accepts TV channels from a TV content provider into the TV Connect Head End either or uncompressed SD or HD SDI via the BT FacilityLine Plus service (or via the Openreach Broadcast Access Product 3Gb HD-SDI Quad Unidirectional if UHD) compressed via the TVC Multicast Ingest Point (MIP) capability. If uncompressed, TV channels are checked for quality and encoded within the Head End; the post encoded channels are passed back to the ISP for encryption and then returned to the Head End (via separate Ethernet interfaces), then processed to enable error recovery via Forward Error Correction (FEC) if selected by the ISP, and appropriate Service IP Addressing. If compressed (encoded/encrypted), TV channels are checked and policed at the Multicast Ingest Point (MIP) to ensure that a) the maximum per channel bandwidth, as contracted by the ISP is not exceeded and b) that the maximum overall bandwidth envelope for all channels, as contracted by the ISP is not exceeded. This version of the service does not support error recovery via Forward Error Correction (FEC), but does provide appropriate Service IP Addressing. The TV Connect service delivers multicast channels to end users via MSANs and Openreach GEA. A combination of IP and Ethernet Multicast within BT s 21C core, at the MSAN (copper access), and within the Openreach GEA equipment (fibre access, FTTC and FTTP), is then used to replicate and deliver TV Connect Channels to WBC End Users (EUs). The service is designed for high availability, so TV Connect traffic is delivered over resilient paths into and across the BT Wholesale 21C infrastructure to MSANs and Openreach GEA handover points. SIN 511 Issue 1.9 British Telecommunications plc Page 9 of 33

10 2.3.2 End-To-End Service Flow Example (Fibre access, FTTC and FTTP via Openreach GEA) An overview of end user end-to-end flows for an end user connected via Openreach GEA is illustrated in Figure 4. ISP Encryption/Encoding Openreach SMPF Compressed, Encrypted TV Content In MSAN STB MIP 1 FTTP Residential Gateway EEA EEA 21C Core MAR MAR 4 x EAD Uncompressed TV Content In 4 FTTC PON DSLAM L2S Openreach GEA EES Openreach Cablelink 3 5 BRAS/LAC Broadband ISP BEA MSIL ISP N/W 6 MSIL BT Wholesale ISP N/W 7 LNS FacilityLine Plus Or Openreach Broadcast Access Product 3Gb Channel join request Figure 4 End to End flows for an end user connected via fibre, FTTC and FTTP via Openreach GEA 1. End user issues channel join request via Set Top Box 2. Home router issues proxy request into TV Connect path to Openreach GEA head end 3. Home router replicates proxy request and issues it into PPP path to BRAS 4. Openreach GEA head end receives proxy request from home router and delivers requested channel to end user 5. BRAS receives proxy request from home router and shapes broadband end user broadband PPP session to a rate reduced by an amount equal to requested TV channel bandwidth. 6. In the case of an ISP taking the L2TP handover option for WBC, the home router replicates the proxy request so that it is forwarded via the PPP session over an L2TP tunnel from the LAC within the BT platform to the LNS within the ISP s network. 7. The LNS within the ISP s network receives the proxy request and is expected to shape the broadband end user PPP session to a rate reduced by an amount equal to the requested TV channel bandwidth. SIN 511 Issue 1.9 British Telecommunications plc Page 10 of 33

11 Channel Leave Request The channel leave request sequence functions in a similar fashion. 1. End user issues channel leave request via Set Top Box 2. Home router issues proxy request into TV Connect path to Openreach GEA head end 3. Home router replicates proxy request and issues it into PPP path to BRAS 4. Openreach GEA head end receives proxy request from home router and stops delivering the specified channel to the end user 5. BRAS receives proxy request from home router and removes the shaping on the broadband end user broadband PPP session by an amount equal to the bandwidth of the TV channel specified in the leave request. 6. In the case of an ISP taking the L2TP handover option for WBC, the home router replicates the proxy request so that it is forwarded via the PPP session over an L2TP tunnel from the LAC within the BT platform to the LNS within the ISP s network. 7. The LNS within the ISP s network receives the proxy request and is expected to remove the shaping on the broadband end user PPP session by an amount equal to the bandwidth of the TV channel specified in the leave request End-To-End Service Flow Example (Copper access from an MSAN) An overview of end user end-to-end flows for an end user connected to an MSAN is illustrated in Figure 5. ISP Encryption/Encoding Openreach SMPF Compressed, Encrypted TV Content In STB FTTP 1 4 Residential Gateway 2 MSAN EEA EEA C Core MAR MAR 4 x EAD MIP Uncompressed TV Content In PON L2S EES 5 BRAS/LAC BEA BT Wholesale DSLAM Openreach Cablelink FTTC Openreach GEA Broadband ISP MSIL ISP N/W MSIL ISP N/W LNS 7 FacilityLine Plus Or Openreach Broadcast Access Product 3Gb Figure 5 End to End flows for an end user with copper access connected to an MSAN SIN 511 Issue 1.9 British Telecommunications plc Page 11 of 33

12 Channel Join Request 1. End user issues channel join request via Set Top Box. 2. Home router issues proxy request into TV Connect path to MSAN. 3. Home router replicates proxy request and issues it into PPP path to BRAS. 4. MSAN receives proxy request from home router and delivers requested channel to end user. 5. BRAS receives proxy request from home router and shapes the broadband end user s PPP session to a rate reduced by an amount equal to the requested TV channel bandwidth. 6. In the case of an ISP taking the L2TP handover option for WBC, the home router replicates the proxy request so that it is forwarded via the PPP session over an L2TP tunnel from the LAC within the BT platform to the LNS within the ISP s network. 7. The LNS within the ISP s network receives the proxy request and is expected to shape the broadband end user PPP session to a rate reduced by an amount equal to the requested TV channel bandwidth. Channel Leave Request The channel leave request sequence functions in a similar fashion. 1. End user issues channel leave request via Set Top Box. 2. Home router issues proxy request into TV Connect path to MSAN. 3. Home router replicates proxy request and issues it into PPP path to BRAS. 4. MSAN receives proxy request from home router and stops delivering the channel down to the end user. 5. BRAS receives proxy request from home router and removes the shaping on the broadband end user s PPP session by an amount equal to the bandwidth of the TV channel specified in the leave request. 6. In the case of an ISP taking the L2TP handover option for WBC, the home router replicates the proxy request so that it is forwarded via the PPP session over an L2TP tunnel from the LAC within the BT platform to the LNS within the ISP s network. 7. The LNS within the ISP s network receives the proxy request and is expected to shape the broadband end user PPP session to a rate reduced by an amount equal to the requested TV channel bandwidth. SIN 511 Issue 1.9 British Telecommunications plc Page 12 of 33

13 3. BT Wholesale Hosted TV Encoding Head End 3.1 Channel Ingress to TV Connect Head End. Presentation of SD or HD programme sources from the ISP s or Content Provider s network to the TVC Head End will be by the BT Wholesale FacilityLine Plus product; this product falls outside the scope of TV Connect. Presentation of UHD programme sources from the ISP s or Content Provider s network to the Head End is expected to be by the Openreach Broadcast Access 3Gb HD-SDI Quad Unidirectional product: this product falls outside the scope of TV Connect. The TV Connect Head End is designed to accept dual feeds of each programme source from the ISP or Content provider in order to ensure high availability of content. Technical information on FacilityLine Plus is available from BT Wholesale [9]. Technical information on Broadcast Access 3Gb Product is available from Openreach. [13]. 3.2 Ingress of Standard Definition Video SDI General Conform to ITU-R BT.601 and ITU-R BT.656 at 270 Mbit/s [6] Or the equivalent SMPTE 259M [3] Contain audio embedded according to SMPTE 272M [3] Video Video will be 625 lines 50 fields (625/50) Active Picture 576 lines interlaced (576i50). Aspect Ratio will be 4:3 or 16:9 static or variable AFD signalling to SMPTE RP186 is required to support variable aspect ratio channels. [3] Audio Main Programme Main Programme Audio shall be carried as embedded audio in the video signal according to SMPTE 272M [3]. Main Programme audio is English unless otherwise stated It shall occupy Group 1 - Audio 1 and 2 It shall be either Stereo or Dual Mono It shall be 48khz AAC Audio Audio Description Broadcaster Mix (AD-BM) Audio Description Broadcaster Mix /Premix content will be presented as premixed main plus description stereo track in channels 9 and 10, and shall be delivered to TV Connect embedded in the parent SDI video signal: : SIN 511 Issue 1.9 British Telecommunications plc Page 13 of 33

14 Audio Description Broadcaster Mix /Premix audio content shall carried as embedded audio in the video signal according to SMPTE 299M [3] Audio Description Broadcaster Mix /Premix audio is English unless otherwise stated. It shall occupy audio channels 9 and 10 (SDI Group 3 audio 1 and 2) It shall be either Stereo or Dual Mono It shall be 48khz AAC Audio Audio Description Broadcaster Mix will be encoded in the same way as the main programme but tagged as an Audio Description Broadcaster Mix to enable STBs to distinguish between this and standard main audio. Only AD-BM or AD-STBM (see below) is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported. Use of AD-BM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo sound), and the choice of stereo or dual-mono AD-BM is independent on the stereo choice for Main Programme audio Audio Description Set Top Box Mix (AD-STBM) Audio Description STB-Mix content shall be delivered to TV Connect embedded in the parent SDI video signal as follows: Audio shall be presented as channel 7 (SDI Group 2 Audio 3) Data - shall be presented as channel 8 (SDI Group 2 Audio 4) Only AD-BM (see above) or AD-STBM is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported. Use of AD- STBM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo sound) Subtitles The ability to insert DVB subtitling on the TV Connect Channels relies on the information being available as a data stream carried within the programme video, supplied to the TVC Head End. For SD content feeds, this will be provided as Teletext (SDI) data in the VBI. SIN 511 Issue 1.9 British Telecommunications plc Page 14 of 33

15 3.3 Ingress of High Definition Channels - HD-SDI General Conform to SMPTE 292M at 1.5 Gbit/s [3] Contain audio embedded according to SMPTE 299 [3] Video Video will be 1125 lines 50 fields (1125/50)or 750 lines 25 frames progressive (750/25p) Active Picture 1080 lines 50 fields interlaced (1080i50) or 720 lines 25 frames progressive (720P25) Aspect Ratio will be 16:9 AFD Signalling is required Audio Main Programme Stereo Audio Main Programme Audio shall carried as embedded audio in the video signal according to SMPTE 299M [3] Main Programme audio is English unless otherwise stated. It shall occupy Group 1 - Audio 1 and 2 It shall be either Stereo or Dual Mono It shall be 48khz AAC Audio Surround Sound Delivery from the ISP as a Dolby E encoded audio stream embedded in the video is considered the default. Further details on options will be available at a later date Audio Description Broadcaster Mix (AD-BM) Audio Description Broadcaster Mix /Premix content will be presented as premixed main plus description stereo track in channels 9 and 10, and shall be delivered to TV Connect embedded in the parent SDI video signal: : SIN 511 Issue 1.9 British Telecommunications plc Page 15 of 33

16 Audio Description Broadcaster Mix /Premix audio content shall carried as embedded audio in the video signal according to SMPTE 299M [3] Audio Description Broadcaster Mix /Premix audio is English unless otherwise stated. It shall occupy audio channels 9 and 10 (SDI Group 3 audio 1 and 2) It shall be either Stereo or Dual Mono It shall be 48khz AAC Audio Audio Description Broadcaster Mix will be encoded in the same way as the main programme but tagged as an Audio Description Broadcaster Mix to enable STBs to distinguish between this and standard main audio. Only AD-BM or AD-STBM (see below) is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported. Use of AD-BM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo or surround sound), and the choice of stereo or dual-mono AD-BM is independent on the stereo choice for Main Programme audio Audio Description Set Top Box Mix (AD-STBM) Audio Description Set Top Box Mix content shall be delivered to TV Connect embedded in the parent SDI video signal as follows: Audio shall be presented as channel 7 (SDI Group 2 Audio 3) Data - shall be presented as channel 8 (SDI Group 2 Audio 4) These tracks shall not contain content other than audio description. Only AD-BM (see above) or AD-STBM is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported. Use of AD- STBM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo or surround sound) Subtitles The ability to insert DVB subtitling on the TV Connect Channels relies on the information being available as a data stream carried within the programme video, supplied to the TVC Head end. For HD-SDI the sub-titling information will be provided to TV Connect as data within the video as defined in OP 47 [8]. The OP47 document specifies the carriage of data in the VANC payload of the HD-SDI stream compliant with ITU-R BT and SMPTE 291M. SIN 511 Issue 1.9 British Telecommunications plc Page 16 of 33

17 3.4 Ingress of Ultra High Definition Channels - UHD-SDI General UHD Content will be presented to the Headend as 4 x 3G HD-SDI Level A signals in Square Division Format. Quadrants shall be presented at Head End interfaces in the order : 1 A TL [Top Left] 2 B TR [Top Right] 3 C BL [Bottom Left] 4 D BR [Bottom Right] Port/Circuit numbers shall be used in sequence with Q1 occupying the lowest. Documentation shall use one of the 3 schemes above : Quadrant 1 1,2,3,4 A,B.C.D TL,TR, BL,BR o shall contain audio embedded according to SMPTE 299 [3] o shall contain data for any programme associated services eg Subtitles Any Audio/Data in Quadrants 2,3 and 4 will not be used, except where required to meet the standards listed in section Signal Compliance Customers Signals shall comply with the relevant sections of the following standards : o SMPTE ST 424 o SMPTE ST o SMPTE ST o SMPTE ST o SMPTE ST 274 o SMPTE ST 352 o SMPTE ST Video Each Quadrant Video will be 1125 lines 50 frames progressive (1125/50p) Active Picture 1920 x 1080 lines 50 frames progressive (1080p50) SIN 511 Issue 1.9 British Telecommunications plc Page 17 of 33

18 Aspect Ratio will be 16: Video - Combined Quadrants Video will be 2250 lines 50 frames progressive (2250/50p) Active Picture 3840 x 2160 lines 50 frames progressive (2160p50) Aspect Ratio will be 16: Audio Main Programme Main Programme shall be in one of the following formats : Stereo Audio Main Programme Audio shall carried as embedded audio in the video signal according to SMPTE 299M [3] as PCM Main Programme audio is English unless otherwise stated. It shall occupy Group 1 - Audio 1 and 2 It shall be either Stereo or Dual Mono It shall be 48khz Stereo or Surround Sound Delivery from the ISP as a Dolby E encoded audio stream embedded in the video is considered the default. It shall be presented embedded on channels 9 and 10 [group 3 pair 1] Dolby E placement shall be between lines 37 and 46 as recommended by Dolby Labs Audio Description Broadcaster Mix (AD-BM) Audio Description Broadcaster Mix /Premix content will be presented as premixed main plus description stereo track in channels 11 and 12, and shall be delivered to TV Connect embedded in the parent SDI video signal: : Audio Description Broadcaster Mix /Premix audio content shall carried as embedded audio in the video signal according to SMPTE 299M [3] Audio Description Broadcaster Mix /Premix audio is English unless otherwise stated. It shall occupy audio channels 11 and 12 (SDI Group 3 audio 3 and 4) It shall be either Stereo or Dual Mono It shall be 48khz AAC Audio Audio Description Broadcaster Mix will be encoded in the same way as the main programme but tagged as an Audio Description Broadcaster Mix to enable STBs to distinguish between this and standard main audio. SIN 511 Issue 1.9 British Telecommunications plc Page 18 of 33

19 Only AD-BM or AD-STBM (see below) is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported. Use of AD-BM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo or surround sound), and the choice of stereo or dual-mono AD-BM is independent on the stereo choice for Main Programme audio Audio Description Set Top Box Mix (AD-STBM) Audio Description Set Top Box Mix content shall be delivered to TV Connect embedded in the parent SDI video signal as follows: Audio shall be presented as channel 5 (SDI Group 2 Audio 1) Data - shall be presented as channel 6 (SDI Group 2 Audio 2) These tracks shall not contain content other than audio description. Only AD-BM (see above) or AD-STBM is supported on a single channel the use of both types of Audio Description delivery for the same channel is not supported Use of AD- STBM for a single channel can only be selected once a Main Programme audio format is selected (i.e. stereo or surround sound). Subtitles The ability to insert DVB subtitling on the TV Connect Channels relies on the information being available as a data stream carried within the programme video, supplied to the TVC Head end. For UHD-SDI the sub-titling information will be provided to TV Connect as data within the video as defined in OP 47 [8]. The OP47 document specifies the carriage of data in the VANC payload of the UHD-SDI stream compliant with ITU-R BT and SMPTE 291M. 3.5 Content Delivery A TV Content Stream can be delivered with a variety of different distribution profiles. Please speak to your BT Wholesale representative about specific requirements. 3.6 Packaging Each of the content streams created as above will be packaged into an MPEG-2 Single Programme Transport Stream (SPTS). 3.7 Encryption Stream encryption for conditional access to a channel is the responsibility of the ISP (See section 3.10 below). 3.8 Forward Error Correction Forward Error Correction may be applied to each stream based on a number of profiles in line with the SMPTE standard [4]. The FEC scheme profile will be agreed with the ISP on completion of the Customer Requirements Form (CRF). Note that FEC is not available for UHD streams. SIN 511 Issue 1.9 British Telecommunications plc Page 19 of 33

20 3.9 SDI Channel Egress from TV Connect Head End The ISP may opt to have their TV Channel content extracted from the TV Connect Head End in exactly the same SDI format as that provided into the TV Connect Head End, but after the point where the TV Connect Head End has monitored ingress and selected the better of the dual fed inputs described in section 3.1. The interface from the TV Connect Head End will be via two allocated SDI egress ports per channel (2x4 SDI egress ports for UHD channels) and the ISP will provide SDI connectivity to those allocated egress ports from their equipment. The format of the SDI content will be exactly as provided by the ISP on their Channel Ingress connectivity and so should conform to the standards described in sections 3.2 and 3.3. Any deviation from these standards on ingress will be reflected in egress Securing Access to Content The ISP will supply their own method of encrypting channels to support conditional access (CA). The ISP should agree a form of encryption with BT Wholesale that is compatible with the TV Connect platform Overview Connection to the TVC Head End from the ISPs Conditional Access device will be via two ports (egress and ingress) on each of the two TV Connect Head End stream aggregation switches, at each site where connectivity is required. (Two switches are provided for resilience). Each of the two egress connections (from TVC Head End to CA device) will carry all of the clear video channels to be encrypted. The ISP will ensure that each of the two ingress connections (from CA device to TVC Head End) will carry all of the encrypted video channels to be multicast across the network to end users and that the content on each connection is identical. GE Port GE Port Clear Video, Audio, Subtitles etc TVC HE Stream Aggregation Switch TVC HE Stream Aggregation Switch Encrypted Video, Audio, Subtitles etc + STB Management Channel (EMM) If Required Egress Port* Ingress Port* Clear Video, Audio, Subtitles etc ISP s Encryption ISP s Device(s) Encryption (Scrambler) Device(s) (Scrambler) Encrypted Video, Audio, Subtitles etc + STB Management Channel (EMM) If Required * There is one egress port and one ingress port per Head End stream aggregation switch, of which there are two per headend site. Figure 6 ISP Conditional Access Support SIN 511 Issue 1.9 British Telecommunications plc Page 20 of 33

21 Conditional Access Interfaces between TVC Head End and ISP CA/Encryption device The ISP may provide encryption devices (scramblers) for connection to the Head End. The scrambler or scramblers can be located locally (within range of CAT5 cable, 100 metres maximum) or remotely in a location to be agreed with the ISP. For scramblers that are remotely located the ISP will be responsible for the provision of interconnecting access circuits and any associated security arrangements. Each pair of egress and ingress streams will be effectively inserted in the X and Y redundant paths of the TV Connect Head End. Clear multicast programme streams are sent to the CA System, with Encrypted Programme Streams being returned to the TV Connect Head End, along with any supporting data streams (not supplied into the CA system from the TV Connect Head end but inserted by the CA system) such as Entitlement Management Messages. Two Gigabit Ethernet links (1000BASE-T) are presented to the ISP encryption device over cat 5/6 cables carrying clear channels [7]. Two Gigabit Ethernet ports (1000BASE-T) are available on the Head End to accept the encrypted programme streams from the ISP [7]. All signals between the encryption system and the Head End will be carried over these physical links. It is assumed that the programme streams traversing these links will be properly conformed MPEG2 Single Programme Transport Streams [2]. The ISP should provide a means of decryption (set top box or equivalent) for use by BT Wholesale within the Head End to allow monitoring of TV channels post encryption Ports and Addressing The multicast addresses and UDP port numbers for clear programme streams that ingress the ISP encryption devices should be agreed with BT Wholesale. The multicast addresses and UDP port number for encrypted programme streams that egress the ISP encryption device should correspond to those agreed on the Customer Requirements Form (CRF). A default UDP port number of 5802 will be used on the CRF for the main programme stream and a default UDP port number of 5804 will be used on the CRF for the FEC stream if it has been selected by the ISP. Other UDP port numbers may be used by agreement via the CRF Entitlement Management Messages (EMM) Update/Announce This section applies to any ISP that requires a management channel for EMM Update/Announce. It is expected that this channel will be provided by the ISP as an additional multicast MPEG2 transport stream [2] containing data only and that no FEC is required to be applied to the channel. The data rate for the EMM Update/Announce channel is expected to be of low rate in comparison to a Standard Definition channel, typically in the region of 100 kbit/s. It is expected that this EMM Update/Announce channel will be transported over the same links that carry the encrypted programme streams. SIN 511 Issue 1.9 British Telecommunications plc Page 21 of 33

22 4. ISP Multicast Ingestion into TVC 4.1 Channel Ingress to TV Connect Head End. Presentation of [ISP encoded and encrypted] programme sources from the ISP s network to the TVC Head End will be by Gigabit Ethernet links. The number of links provided will depend on the resilience option selected by the ISP (see Section above). The ISP devices to be connected into the TVC Multicast Ingest Point (MIP) can be located locally (within range of CAT5 cable, 100 metres maximum) or remotely in a location to be agreed with the ISP. For devices that are remotely located the ISP will be responsible for the provision of interconnecting access circuits and any associated security arrangements. BT recommends the use of the Openreach Ethernet Access Direct (EAD) products. At least two Gigabit Ethernet ports (1000BASE-T) are available on the TVC MIP to accept the programme streams from the ISP [7], the location and number of ports is dependent on the ISP option chosen as illustrated in Figure 2. All signals between the ISP (encryption system) and the Head End will be carried over these physical links. It is assumed that the programme streams traversing these links will be properly conformed MPEG2 Single Programme Transport Streams [2]. MIP will police ISP ingest bandwidth to ensure that: The overall bandwidth offered by the ISP into TVC does not exceed the overall bandwidth envelope agreed with BT Wholesale. The individual channel bandwidth of each channel offered by the ISP into TVC does not exceed the individual channel bandwidth agreed with BT Wholesale. 5. Summary of Potential Content Routeing and Processing Headend Options This section gives an overview summary review of the Headend feature options an ISP may take. The examples below are not exhaustive. There is potential for an ISP to use one or all of these options contemporaneously and potentially different options at each of the Main and Secondary Headend sites. Encoded Content out to ISP for Encryption Encoded Encrypted Content In from ISP Uncompressed Content In from ISP TVC Headend TVC Multicast Distribution to ISPs Consuming End Users ISP TV End user Figure 7 TVC HE Encoding Figure 7 TVC HE Encoding shows the Headend architecture for the original TVC service. SIN 511 Issue 1.9 British Telecommunications plc Page 22 of 33

23 Uncompressed Content Out to ISP (SDI Egress) Encoded Content out to ISP for Encryption Encoded Encrypted Content In from ISP Uncompressed Content In from ISP TVC Headend TVC Multicast Distribution to ISPs Consuming End Users ISP TV End user Figure 8 TVC SDI Egress Figure 8 TVC SDI Egress shows the incremental option for an ISP to receive a copy of the validated SDI feed that is being delivered to the TVC HE encoders. Uncompressed Content Out to ISP (SDI Egress) Encoded Encrypted Content In from ISP Uncompressed Content In from ISP TVC Headend TVC Multicast Distribution to ISPs Consuming End Users ISP TV End user Figure 9 TVC SDI Egress to ISP Encoding Platform Figure 9 TVC SDI Egress to ISP Encoding Platform shows the option for an ISP to receive a validated SDI feed to encode themselves and then return encoded encrypted content to the TVC Headend for onward multicast distribution. Encoded Encrypted Content In from ISP TVC Headend TVC Multicast Distribution to ISPs Consuming End Users ISP TV End user Figure 10 TVC Multicast Ingest Only Figure 10 TVC Multicast Ingest Only shows the option for an ISP to deliver encoded encrypted content to the TVC Headend for onward multicast distribution. 6. IP Multicast Streams 6.1 Maximum Bandwidth The encoding options (whether encoded by the ISP or by TVC on behalf of the ISP) shall result in SPTS Programme Channels having Multicast IP bandwidths in the Wholesale Network of less than Mbit/sec. 6.2 Channel Aggregation The complete stream will be delivered as an IP Multicast for transport across the core of the 21C network. SIN 511 Issue 1.9 British Telecommunications plc Page 23 of 33

24 6.3 Multicast Source and Group IP addresses The ISP will be expected to complete a Customer Requirements Form (CRF) in conjunction with BT Wholesale. Multicast group and source addresses, from a range of IP addresses owned by BT Wholesale, will be allocated to individual TV Channels in agreement with the ISP. The multicast group IP address is used to uniquely identify a particular TV channel. The multicast source IP address is used to identify the network source equipment of the TV channel within the TV Connect Head End and is required for multicast routing and georesilient/tvc Protect failover. 6.4 Retransmission In order to facilitate packet repair by retransmission by the ISP, a multiplex of all the channels belonging to an ISP may be made available to the ISP at a small set of handover points, which are to be agreed during contract negotiation. Retransmission repair and control packets may be forwarded via the WBC data service. It is recommended that an ISP make use of the priority best effort traffic marking for retransmission repair and control traffic [10] in order to ensure a good experience for end users. 7. TV Connect Customer Premises Equipment (CPE) IGMP Requirements 7.1 Message Sequencing It is expected that IGMPv3 will be used to signal access to TV Connect channels. An end user will be joined to a selected channel via Openreach GEA fibre to the cabinet (FTTC) and fibre to the home (FTTP). The IGMP messaging sequence is indicated below in Figure 11. SIN 511 Issue 1.9 British Telecommunications plc Page 24 of 33

25 TV Connect Network IGMP sequence details Unsolicited IGMP messages, and reports in response to queries STB RG DSL MSAN 7 2 General & Specific IGMP Queries General & Specific IGMP Queries 6 /OR GEA Unsolicited IGMP messages 5 4 TV Connect Traffic Hierarchical Shaping BRAS Downstream Broadband Traffic EU IGMP Domain RG Forks IGMP messages Multicast Group to Bandwidth Table (maintained by OSS) Key: Multicast path Broadband path Figure 11 TV Connect IGMP flows 7.2 Set Top Box (STB) Functions The set top box will generate IGMP join and leave messages in response to end user requests (e.g. channel selection changes) and respond to IGMP query requests (from upstream network equipment). The set top box may use the WBC service to communicate with retransmission servers for packet repair or access other ISP services. 7.3 Residential Gateway (home router) Functions [5] The End user Residential Gateway (RG) acts as an IGMP proxy routing agent, supports IGMP snooping and forks IGMP messages for sending up the TV Connect and Broadband paths Support for IGMPv3 is required on the Residential Gateway The TV Connect product will only support IGMPv3 [1] The TV Connect product will support IGMPv3 Any Source Multicast (*,G). The TV Connect product will not support IGMPv3 Source Specific Multicast (S,G). SIN 511 Issue 1.9 British Telecommunications plc Page 25 of 33

26 The IGMP protocol has no acknowledgements, in consequence Multiple IGMP requests are to be sent by the Residential Gateway. 2 IGMP requests should be sent initially (IGMPv3 default setting). The robustness variable setting may be adjusted if required in consultation with BT Wholesale during trials. The Unsolicited report intervals should be set to 1 second initially (IGMPv3 default setting). The Residential Gateway should prioritise IGMP joins and leaves upstream (802.1p marking of 3 or above) Responses to IGMP Queries (keep-alives) by the Residential Gateway shall only be returned over the interface through which the Queries were received. For an end user connected via Openreach GEA (FTTC and FTTP) The Residential Gateway will support IpoE for multicast traffic and PPPoE for BB traffic VLAN tag ID of 0 or no VLAN tag ID for multicast and BB traffic Fork IGMP requests for sending up multicast and BB paths. More details on the support of Multicast via Openreach GEA (FTTC and FTTP) including features such as fast leave are described in SIN 503 [11] The BRAS will adjust the rate of the PPP session on a receipt of an IGMP join/leave by an amount equal to the bandwidth of the channel specified in the join/leave. The BRAS will respond to IGMP joins/leaves after a configurable delay with a default setting of 1s. The BRAS will send IGMP queries independently of the Openreach GEA equipment The BRAS will send periodic IGMP queries over the PPPoE session General queries will be sent at a default interval of 125s with a default maximum response time of 10s The BRAS will use a robustness variable setting of 3 as default. Settings for timer values and robustness variables may be adjusted in consultation with BT Wholesale during trials. For an end user connected to an MSAN (WBC copper) The Residential Gateway will support a dual VC architecture SIN 511 Issue 1.9 British Telecommunications plc Page 26 of 33

27 Accept TV Connect multicast traffic on ATM VP/VC 0/35 with IpoE and broadband traffic on ATM VP/VC 0/38 with PPPoE Fork IGMP requests for sending up multicast and broadband paths The MSAN will send periodic IGMP queries General queries will be sent at a default interval of 125s with a default maximum response time of 100s. Specific queries will be sent at a default interval of 10s with a default maximum response time of 8s. The MSAN will use a robustness variable setting of 2 as default. The MSAN will support the fast leave mode of IGMP. For an ISP utilising the L2TP handover service option for WBC, the ISP will be expected to provide similar IGMP aware line shaping functionality to that of the BT BRAS. The ISP LNS will adjust the rate of the PPP session on a receipt of an IGMP join/leave by an amount equal to the bandwidth of the channel specified in the join/leave. The ISP LNS will respond to IGMP joins/leaves after a configurable delay with a default setting of 1s. The ISP LNS will send IGMP queries independently of the Openreach GEA equipment The ISP LNS will send periodic IGMP queries over the PPPoE session General queries will be sent at a default interval of 125s with a default maximum response time of 10s The LNS will use a robustness variable setting of 3 as default. Settings for timer values and robustness variables may be adjusted in consultation with BT Wholesale during trials. 8. Service Availability Only a WBC customer (ISP) can take up the TV Connect service. The TV Connect service is available to ISPs that take the WBC PTA (PPP termination and aggregation service) or L2TP (Layer 2 tunnelling protocol) handover service. An ISP can check the availability of Multicast at WBC exchanges by using the Broadband Availability Checker available at via the Routing and Planning section under the Applications tab. 9. ISP Responsibilities The ISP will be responsible for End User engagement, including client management (e.g. client streaming, updates, and problem resolution) SIN 511 Issue 1.9 British Telecommunications plc Page 27 of 33