Executive Summary Sun Microsystems, Inc.
Offering video services over existing IP networks holds considerable promise in terms of
new revenue and business growth opportunities for video service providers. Home
video in all of its forms is now a large and growing business, and video on demand
(VoD), networked personal video recorders (nPVR), and interactive video services can
offer considerable convenience and tailored services in an already strong market. Early
indications are that a large percentage of broadband customers would subscribe to
interactive video services, with considerable potential for growth.
This promise is offset by the challenges of designing and deploying scalable, reliable,
and cost-effective infrastructure for television services over IP networks (IPTV). Both
subscribers and operators expect a highly reliable service and downtime is a threat to
customer satisfaction. In addition, since IPTV requires signiﬁcantly more components
than a conventional broadcast video service, it is important that architectures support
cost-effective redundancy and failover mechanisms, along with systematic scalability to
match growing demand.
Unfortunately, traditional disk based video server architectures often lack the scalability
needed to address a large customer base with an appetite for a diverse range of video
titles. The relatively low number of streams served by individual disk-based servers
means that very large numbers of servers and disks must be deployed to serve
anticipated growth. These large deployments drive accompanying complexity and
server sprawl, and add to networking and system administration cost burden.
Complicating matters, many IPTV solutions have proprietary elements that serve to lock
organizations into the innovations of a single vendor.
The innovative Sun Streaming System overcomes these issues with a solution that
meets scalability, cost, and availability requirements with an open and standards based
approach. With high-speed memory-based streaming and a signiﬁcant degree of
integration, the Sun Streaming System provides a cost-effective end-to-end solution for
centralized interactive television networks capable of supporting the largest and most
demanding deployment requirements. This paper describes the challenges faced by
video service operators as they deploy IPTV, and also describes the Sun Streaming
System components and software architecture. Examples are also provided to illustrate
how the Sun Streaming System ﬁts into video services network architecture based on
2 Redeﬁning Video over IP Sun Microsystems, Inc.
Redeﬁning Video over IP
Consumers of video services are moving away from traditional broadcast models
toward services that provide them with more channels and more choice, both in how
and what they view.
• Personal video recorder (PVR) services and digital video recorder (DVR) devices are
becoming common, primarily for time-shifting of regular TV programming, but also
for skipping mass-market advertisements that are not targeted to individual
• Video on demand (VoD) is now available in many major cable markets, and the size of
content libraries continues to increase.
• Broadcast television advertising revenue is ﬂattening in many major cable markets,
as advertisers shift spending to more targeted advertising opportunities.
These trends are promising indeed for video service operators and others poised to
provide ﬂexible digital IP based television services over their broadband networks.
Personalized television services
The opportunity to deliver personalized video entertainment to each subscriber is
signiﬁcant. Innovative and targeted services promise to capture new customers and aid
in retention of those customers for other services. Service providers stand to gain from
providing “triple-play” strategies, delivering voice, video, and data to their customer
base. The result can be more choice for customers while helping to enable higher
revenue streams for service providers.
Growth in spending on video entertainment in the past few years has coincided with
reduced spending on other services such as long-distance and local telephony. While
communication and video entertainment services are certainly distinct, this trend may
serve service providers by equalizing the revenue opportunities with existing
customers. For others, IP networks provide an ideal medium for delivering interactive
digital video services. Coupled with existing investments in network infrastructure
made over the last 10 years, a signiﬁcant opportunity exists in delivering on-demand or
interactive video and television services using Internet broadband architecture. This
opportunity is particularly attractive given new technology advances that are driving
down the cost per individual delivered video stream.
3 Redeﬁning Video over IP Sun Microsystems, Inc.
IPTV broadband requirements
To be cost-effective, IPTV architecture must leverage existing IP broadband
infrastructure. In addition, any proposed architecture must be able to scale, both in the
number of streams delivered, and in the basic manageability of the infrastructure
involved. IPTV architectures will fail unless they can scale to handle the growth of
subscribers and the shift from standard to high-deﬁnition TV.
IPTV requires a high-bandwidth IP network connected to the home. Fortunately, a
number of broadband network topologies are available to deliver IP packets over
copper wires (xDSL) or ﬁber (PON, FTTC, or FTTH topologies). Through these
technologies, multiple subscribers are aggregated at the logical level onto higher-speed
connections, giving the subscriber a dedicated switched IP packet connection. This
aggregation takes place with either virtual circuit multiplexing (Level 1), or via Ethernet
switching (Level 2), or IP routing (Level 3). In any of these scenarios, the subscriber is
provided with a dedicated, switched IP packet connection.
Despite the use of Internet technology, IPTV has requirements that are distinct from a
conventional Internet services:
• Unlike Internet services, interactive television and video services do not originate
from the Internet but rather from the internal network of the video service operator,
reducing demands on Internet bandwidth.
• Unlike traditional IP based services that can accept some level of packet loss or
retransmissions, video services require reliable transmission of packets to the
subscriber. Broadband networks must have the necessary bandwidth, and must be
engineered to provide the high-quality services that customers demand.
• Unlike traditional IP applications, video service trafﬁc is largely unidirectional as it
originates from a video server and terminates on a set-top box.
The exact bandwidth provisioned per subscriber depends on the encoding of the video
stream, the resolution of the video content, and the number of streams supported per
household. A data rate of 2 Mbps is sufﬁcient for one H.264/AVC standard deﬁnition
stream, whereas a high deﬁnition stream will require approximately 8 Mbps.
Deployment considerations for IPTV involve whether to select centralized or distributed
topologies, or a mixture of both. A centralized headend or video hub ofﬁce (VHO) with
optical transmission streams to locations of broadband distribution is generally lower
cost than a distributed video server architecture that replicates content and video
streams in multiple locations. The economic trade-off is the cost of transmitting video
streams over high-bandwidth ﬁber versus the cost of replicating and maintaining video
servers in remote distribution hubs.
4 Redeﬁning Video over IP Sun Microsystems, Inc.
With the latest optical transmission technology, it is now possible to transmit high
bandwidth video over long distances. For example, 80 Gbps video can be sent using
coarse wavelength division multiplexing (CWDM) and 320 Gbps video can be sent using
dense wavelength division multiplexing (DWDM). As long as ﬁber is available, there is
virtually no limitation to the number of virtual private video streams that can be
transmitted from a central location, greatly reducing equipment and operational costs.
Since all new generations of last-mile access broadband technologies can handle the
necessary data rates per subscriber, the real challenge is in engineering a service
delivery platform that can be operated and managed cost-effectively. Most existing
video delivery platforms rely on very large numbers of distributed, small-scale video
servers — making it difﬁcult to provide a cost-effective and compelling service:
• Supporting thousands of geographically distributed servers is an expensive and
• Distributed, small-scale locations often provide a hostile environment that reduces
the reliability of equipment
• Distributed resources are difﬁcult to share, leading to resource replication, content
replication, and increased cost
The Sun Streaming System: open, innovative, and scalable
Responding to these challenges and opportunities, the Sun Streaming System
represents a truly disruptive solution for service providers who want to increase average
revenue by delivering IPTV services to their subscribers. By tightly integrating best-of-
breed products from Sun and key third parties, the Sun Streaming System provides a
focused and scalable streaming solution with signiﬁcant advantages, including:
• Reducing the cost of deploying and scaling the streaming media platform and
therefore reducing capital expenses
• Reducing operational expenses for the IP television business through consolidation of
equipment and simpliﬁcation of the network architecture
• Reducing both cost and time-to-market for the introduction of new services through
the aggressive use of open Internet standards
The Sun Streaming System reduces the cost of IP television services to the extent that
service providers can aggressively market these new personalized television services to
their subscribers to drive large-scale adoption and use. The result can be increased
5 Redeﬁning Video over IP Sun Microsystems, Inc.
bandwidth usage, increased revenue, and greater subscriber loyalty. The Sun Streaming
System represents an integrated, ﬂexible, and scalable architecture depicted from a
high level in Figure 1.
Content Controller node(s) Streaming Software Servers
Session Controller node(s) (Sun Fire X4100 servers)
Import Pre-Processor node(s)
Media Store nodes Sun Fire X4500 server(s)
Sun Fire X4950
Streaming Service nodes
Sun Streaming Software Sun Streaming Hardware
Figure 1. High-level block-level diagram of the Sun Streaming System
Key beneﬁts of the Sun Streaming System include:
• Improved economics
The Sun Streaming System offers signiﬁcantly improved economics for video
streaming and content storage. Smaller numbers of high-performance systems
and components coupled with a high level of integration of both servers and
networking eliminates separate networks and boxes. Sun’s solution also provides
considerable consolidation opportunities over traditional video server
Management of video services is simpliﬁed and secured through role-based access
control and authentication. Digital access management and conditional access
system (CAS) integration means that providers aren’t loosing revenue through
theft. An open-systems approach means that the Sun Streaming System is ﬂexible
and integrates well with essential third-party components, easing integration
through open interfaces and providing ﬂexibility for service providers to choose
best of breed third party components.
6 Redeﬁning Video over IP Sun Microsystems, Inc.
• Scalability in multiple dimensions
The Sun Streaming System provides massive scalability that allows operators to
deliver high-capacity unicast video services. The Sun Streaming System provides
multiple, independent dimensions of scalability, including:
– Streaming capacity to serve a very large number of concurrent subscribers with
– Session management capacity to help ensure large numbers of coexisting con-
current sessions, high session setup/teardown rates, and low-latency session
control such as processing trick-play events (fast-forward, pause, rewind)
– Content import capacity to allow a high number of multicast linear-TV streams
and VoD assets to be imported concurrently
– Content storage capacity to support a very large number of video titles
• Integration and consolidation
The Sun Streaming System provides integrated multiplexing, switching, and
optical transmission to simplify conﬁgurations and even eliminate the cost of
switched/routed transmission networks.
Key Sun Streaming System technology innovations
The Sun Streaming System can be used as a part of an end-to-end solution for
centralized interactive television networks capable of supporting the largest and most
demanding deployment requirements. The following sections describe the technology
innovations that are key to the functionality of the Sun Streaming System.
• Memory-based streaming, de-coupled from storage
Most conventional video servers are disk based, meaning that they stream video
content directly from hard disk storage. Unfortunately, disk access rates have not
improved signiﬁcantly over time, imposing fundamental limitations to this
approach. As a result, it is difﬁcult to achieve sustained disk data transfer rates of
more than 150 Mbps per disk drive — corresponding to 75 standard deﬁnition
H.264/AVC streams at a data rate of 2 Mbps.
With this performance limit, scaling the number of streams required by a disk-
based streaming solution becomes extremely resource- and space-intensive. For
example, to achieve 1 million streams would require 25,000 disk drives, assuming
that access to these disk drives could be perfectly load balanced. In reality, perfect
load balancing is not feasible, further increasing the number of disk drives
required. The cost, space, power, and reliability issues associated with such a
large number of disk drives make this solution impractical.
The Sun Streaming System architecture addresses the disk bandwidth bottleneck
by using a large amount of solid-state memory as a cache for frequently accessed
content. With up to 1 terabyte (TB) of DRAM memory, the Sun Fire X4950
Streaming Switch can cache up to 1,000 hours of frequently accessed high-quality
7 Redeﬁning Video over IP Sun Microsystems, Inc.
MPEG2 streams. For example, each Sun Fire™ X4950 Streaming Switch shared
memory system has sufﬁcient bandwidth to service 80,000 simultaneous 4 Mbps
streams or 160,000 2Mbps streams. Within the Sun Streaming System, video
content is stored on Sun Fire X4500 servers that provide content storage in
increments of 24 terabytes. Each Sun Fire X4500 server provides up to 4,700 hours
of high-quality MPEG2 content, including trick-play overhead (indexed fast forward
and rewind streams at multiple speeds). Content is automatically moved from Sun
Fire X4500 servers into the Sun Fire X4950 Streaming Switch cache based on
content access patterns.
• Network integration and consolidation
In a conventional IP television architecture, banks of video servers connect to the
broadband network through a separate switch. This approach can add signiﬁcant
cost and complexity to video server solutions since the switch has to be able to
handle large amounts of trafﬁc while minimizing packet loss, latency, and jitter.
The Sun Streaming System architecture integrates the video server and video
switching function into the Sun Fire X4950 Streaming Switch, greatly simplifying
both architecture and implementation. The Sun Fire X4950 Streaming Switch
eliminates the need for a separate network switch to cross-connect a large
number of video servers, and solves the problems associated with packet loss,
latency, and jitter. In addition, even though the Sun Streaming System is
comprised of multiple systems and switches, it functions, and is managed as a
• Optical transport integration
Conventional IPTV architectures employ separate (active) wavelength division
multiplexer (WDM) optical transport equipment, adding to the complexity of
typical deployments. In contrast, the Sun Streaming System architecture
integrates the WDM laser components directly into the Sun Fire X4950 Streaming
Switch, and requires only a passive WDM multiplexer. This level of integration
eliminates the need for another separate active component, further reducing cost
and increasing reliability. The Sun Streaming System approach is to use a 32
lambda or 40 lambda DWDM optical transport, with one 10 Gbps Ethernet
transport per lambda.
The Sun Fire X4950 Streaming Switch directly accepts pluggable XFP DWDM and
does not require separate optical transport equipment, greatly reducing cost.
Inexpensive passive add-on multiplexers are used to add or remove a wavelength
from the ﬁber. Using 40 lambda DWDM, one optical ﬁber can carry 400 Gbps, or
100,000 MPEG2 streams at 4 Mbps.
8 Redeﬁning Video over IP Sun Microsystems, Inc.
• Scalable session management
In a centralized IPTV architecture, a large number of subscribers can be
simultaneously active. Achieving acceptable response times requires considerable
CPU resources to rapidly respond to subscriber requests.
The Sun Streaming System system achieves this level of scalability with multiple
high-density network-based Sun Fire servers based on AMD Opteron™ processors.
These Sun x64 servers can be scaled independently of other components of the
Sun Streaming System to manage concurrent sessions, provide session setup and
teardown, and handle session control such as receiving and managing trick-play
events (forward, pause, rewind). Individual Sun x64 servers act as Sun Streaming
• Network based redundancy
High availability is a key concern for any system where failure can affect a large
number of customers. One key advantage of the Sun Streaming System is that it
can be deployed in an end-to-end redundant architecture, where the failure of any
single component will not affect video streaming operation. In a Sun Streaming
System conﬁguration, multiple Sun Fire X4950 Streaming Switches, multiple Sun
Fire X4500 servers, and multiple Sun x64 servers running Sun Streaming Software
can be deployed for scalability and redundancy — resulting in carrier-grade
reliability. This approach also helps minimize both planned and unplanned
downtime through non-disruptive upgrades and repairs.
9 Sun Streaming System Architecture Sun Microsystems, Inc.
Sun Streaming System Architecture
The Sun Streaming System is not a single product, but rather a collection of hardware,
software, and networking products designed to function as a single system. The Sun
Streaming System is tested and integrated with third-party asset management
software, IPTV middleware software components, and set top boxes (STBs) to help
accelerate and simplify IPTV deployment (Figure 2).
Head-end or VHO Hub Home
Sun Streaming System
Asset Sun Streaming Stream
Set Top Box
Management Software Control
Sun FireX4500 Sun Fire X4950 QAM or Video
Server Streaming Switch DSLAM
Figure 2. Sun Streaming System components integrate with third party asset management and
middleware elements to deliver interactive video streams to the home
While only individual components are implied by the illustration, Sun Streaming
System hardware components can be deployed in multiples to provide scalability and
• Each Sun Fire X4950 Streaming Switch caches popular streams in up to 1 terabytes of
DDR1 memory, providing scalability and consolidating network infrastructure. Each
switch provides up to 32 10 Gb Ethernet connections, supporting up to 160,000
2 Mbps standard-deﬁnition H.264/AVC streams or up to 40,000 8 Mbps high-deﬁnition
• Each Sun Fire X4500 server directly interfaces to at least one Sun Fire X4950
Streaming Switch via a 10 Gb Ethernet connection, and provides 24 terabytes of
storage for video content.
• Multiple Sun x64 servers provide scalability and high-performance resources for a
range of management and control functions, interfacing with third-party asset
management and middleware components. Overall system management, session
control, content control, and import processing functions are provided within Sun
Sun Streaming System components and networking architecture are described in this
chapter with Sun Streaming Software open systems architecture covered in Chapter 3.
10 Sun Streaming System Architecture Sun Microsystems, Inc.
The Sun Fire X4900 Streaming Switch
The Sun Fire X4900 Streaming Switch represents a key innovation for the Sun Streaming
System. Based on industry-standard technology such as DDR1 memory and an X64
based processor, the switch provides cost-effective scalable memory-based streaming.
Each Sun Fire X4950 Streaming Switch offers:
• Up to 1 TB of DDR1 memory
• A 320 Gbps non-blocking cross bar switch (1:1 input/output ratio)
• Up to 32 10 Gb Ethernet optical networking ports from wire-speed streaming engines
This architecture helps ensure that even when a large number of unique streams are
requested, the Sun Fire X4950 Streaming Switch continues to deliver at its committed
rates. In addition, innovative switch design provides a variety of beneﬁts, including:
• Minimal cost per stream
With the Sun Fire X4950 Streaming Switch, the Sun Streaming System effectively
de-couples its DRAM based streaming from storage. Coupled with unidirectional
video networks, this approach provides for a very low cost per stream.
• Simple, cost-effective QoS
The Sun Fire X4950 Streaming Switch integrates video buffering and caching in a
single switch, with optical transport integration based on industry-standard 10 Gb
Ethernet. With a downstream network organized as a simple tree structure, the
Sun Fire X4950 Streaming Switch can provide simple, and highly cost-effective
quality of service (QoS).
• Industry-standard technology
The Sun Fire X4950 Streaming Switch is based on industry standard technology
such as 10 Gb Ethernet, off-the-shelf DRAM, and an X64 based processor.
The Sun Fire X4950 Streaming Switch is provided in a 14 rack-unit (RU) chassis (Figure 3).
Figure 3. The Sun Fire X4950 Streaming Switch provides up to 1 TB of memory-based streaming and
considerable network consolidation and transport integration with up to 32 10 Gb Ethernet outputs
11 Sun Streaming System Architecture Sun Microsystems, Inc.
The Sun Fire X4950 Streaming Switch is speciﬁcally designed to move video data
without introducing arbitrary bottlenecks. Each switch provides an integrated cross-bar
switching fabric with a non-blocking 320 Gbps switching capacity. This design approach
taken is distinct from those that might place a processor or buss in the path of video
data. In the Sun Streaming System, video data enters the switch over a 10Gb Ethernet
connection directly from a Sun Fire x4500 server. The 10Gb Ethernet ports on the switch
feed directly into DRAM where the video data is then available for streaming out to
clients. Figure 4 illustrates the functional block-level diagram of the Sun Fire X4950
Sun Fire X4950 Streaming Switch Chassis
System Mgt. FPGA
Mini Boss DRAM
ECC DDR ECC DDR
PCI-I Central FPGA FPGA
PCI Controller C2SP Tcvr.
INTEL PCI Tcvr.
PCI ECC DDR
10/100 64-bit 16 x 10 Gb Ethernet
ports per card
CPU ECC DDR ECC DDR
BIOS Optical Card
Line Card (Up to two per chassis)
Controller Card (Up to eight per chassis)
(One per chassis)
Figure 4. Functional block diagram of the Sun Fire X4950 Streaming Switch
The Sun Streaming Switch is comprised of the following major components:
• Controller Card — The x64 based Controller Card provides operational and
management support for the Sun Fire X4950 Streaming Switch. With no local disk
drives, the Controller Card boots remotely from the Supervisor node (a specialized
Sun x64 server running Sun Streaming Software). The controller card schedules
incoming data directly to the Line Cards in DMA mode for maximum throughput.
Network interfaces on the Controller Card are used for the Sun Streaming System
internal network and for management of the switch.
• Line Card — Each Line Card provides four on-board FPGA DDR memory controllers and
a total of 64 DDR-1 DIMM slots with 1 GB and 2GB DIMMs supported. With eight Line
Cards, a single Sun Fire X4950 Streaming Switch can provide up to 512 DIMM slots in
a 14U chassis. One DIMM size is supported for all Line Cards in a switch, and the
switch initially supports a maximum of 1 terabyte of memory. The design provides
scalability since no streaming data traverses the link to the controller card.
12 Sun Streaming System Architecture Sun Microsystems, Inc.
• Optical Card — Each Optical Card (up to two per switch) provides 16 10 Gb Ethernet
interfaces utilizing Broadcom BCM8704 controllers. Each group of four 10 Gb Ethernet
ports are directly hard-wired to a single Line Card. Optical Cards are hot-swappable,
but no redundancy is provided between cards since their ports are dedicated to
individual Line Cards.
Switch components and I/O
The front view of the Sun Fire X4950 Streaming Switch chassis is illustrated in Figure 5.
The following modules insert from the front of the chassis:
• A single system Controller Card
• Up to eight Line Cards
• Three hot-swap power supplies that can be inserted and removed without touching
the power cords that connect to connectors in the rear of the chassis
System controller card Up to eight
(up to 1 terabyte)
Figure 5. The system controller card, memory line cards, and hot-swap power supplies are loaded from
the front of the Sun Fire X4950 Streaming Switch chassis
Figure 6 illustrates the rear view of the Sun Fire X4950 Streaming Switch chassis and the
• Two hot-swap Optical Cards (non-redundant) insert from the rear of the chassis
(one shown), together providing support for 32 10 Gb Ethernet ports.
• Nine hot swap 120mm fans are accessible from the rear of the chassis.
• Three independent power plugs are provided on the rear of the chassis.
13 Sun Streaming System Architecture Sun Microsystems, Inc.
Up to 32 10 Gb
9 hot-swap fans
Figure 6. Rear view of Sun Fire X4950 Streaming Switch chassis
The Sun Fire X4950 Streaming Switch Controller Card and Line Cards (Figure 7) work
together to maximize throughput for video streams:
Line Card Controller Card
Figure 7. The Sun Fire X4950 Streaming Switch features a modular architecture designed for maximum
throughput of video streams
The Sun Fire X4500 server
In contrast to traditional system and storage architectures, the Sun Fire X4500 server
deﬁnes a approach that consolidates the server, storage, host bus adapters, switching,
and multiple disk arrays onto a single high-density system. In the Sun Streaming
System, each Sun Fire X4500 server is speciﬁcally conﬁgured for use as a video storage
appliance. Featuring a 4U form factor, the server provides 24 TB of internal storage
14 Sun Streaming System Architecture Sun Microsystems, Inc.
through 48 hard disk drives in a 3.5-inch disk form factor (Figure 8). As used in the Sun
Streaming System, the Sun Fire X4500 server feeds video streams directly to one or
more Sun Fire X4950 Streaming Switches.
SATA disk drives
Figure 8. In the Sun Streaming System, the Sun Fire X4500 server is conﬁgured with 48 disk drives and
supplies video streams directly to the Sun Fire X4950 Streaming Switch over a 10 Gb Ethernet link
Sun Fire X4500 server features
The Sun Fire X4500 server is ideal for integration into the the Sun Streaming System
because of its ability to deliver dense, low-cost media storage along with balanced
system throughput. In the Sun Streaming System, the Sun Fire X4500 server stores
video data from either external decoders or FTP servers, and uploads video data to one
or more Sun Fire X4950 Streaming Switches via a 10 Gb Ethernet link. The Sun Fire
X4500 server provides a scalable and reliable high-density storage solution for the Sun
Streaming System, including:
• Minimal cost per gigabyte utilizing SATA II storage and software RAID 5
• 48 3.5-inch SATA-II disks in a 4U chassis, yielding 24 terabytes of video storage
• 24 terabytes translates to 4,700 hours of MPEG-2 video @ 4 Mbps including trick play
ﬁles (4/10/32x forward and reverse, total of seven speeds)
• High performance from an industry-standard x64 server based on two AMD Opteron
processors with 8 GB of memory
• Six individual PCI disk controllers
• 10 Gb Ethernet output directly to one or more Sun Fire X4950 Streaming Switches
• Redundant, hot-pluggable PSUs, fans, and I/O
• Built-in service processor and graphics card
15 Sun Streaming System Architecture Sun Microsystems, Inc.
Sun Fire X4500 server architecture
The Sun Fire X4500 server features high-performance server engines with dual-socket,
dual-core AMD Opteron processors and high-density storage devices to meet the I/O
requirements of video storage. The system also includes an extensive set of enterprise
class reliability, availability, and serviceability features that reduce hidden service costs
by dramatically simplifying system maintenance.
The system features redundant hot-swappable disk drives, redundant, hot-swappable
fan modules, and redundant hot-pluggable AC power supplies to help enable increased
availability and simpliﬁed serviceability. A battery backup unit is also provided to
prevent data corruption from power failures. In addition, the Sun Fire X4500 server
features remote lights out server management, including remote keyboard, video,
mouse, and storage (RKVMS), remote boot, and remote software upgrades using the
integrated lights out management (ILOM) service processor. Figure 9 illustrates a high-
level block diagram of the Sun Fire X4500 server.
SDRAM SATA HDDs
INTEL 133MHz 6.4 PCI-X
Fw82546 GB/sec Tunnel
GB NIC Marvell
1 GB 88SX6081
1GB/sec PCI-X SATA Ctlr
Fw82546 HT 1 Ghz
GB NIC 8 GB/sec
8111 1GHz SATA Ctlr
Port 1GB/sec SATA Ctlr
1 GB/sec PCI-X
PCI-X SATA Ctlr
ECC DDR 8-port
Figure 9. Sun Fire X4500 server functional block diagram
The Sun Fire X4500 server provides the following architectural features:
• Each AMD Opteron processor features an embedded single-channel DDR memory
controllers. These controllers provide maximum memory capacity and bandwidth
scaling, delivering up to 16 GB of capacity and 12.8 GB/second of aggregated
bandwidth with 2 CPUs and eight 2 GB DIMMS.
• The AMD Direct Connect Architecture directly connects a variety of system
components with HyperTransport links. Processors and AMD PCI-X tunnels are
connected with 1 GB/second HyperTransport links delivering 8 GB/second aggregate
16 Sun Streaming System Architecture Sun Microsystems, Inc.
bandwidth per link. Processors are connected to memory using the integrated DDR
controller delivering 6.4 GB/second.
• Two PCI-X slots deliver high-performance I/O with over 8.5 Gbps of I/O plug-in
bandwidth. (A 10 Gb Ethernet Controller is installed in one PCI-X slot).
• Two Intel 82546GB Dual Port Gb Ethernet controllers server four Gb Ethernet ports
• Six Marvell 88SX6081 SATA II storage controllers connect to 48 high-performance SATA
• Embedded management and legacy I/O support are also included, offering
maximum operational ﬂexibility.
Sun Fire X4500 server I/O
The back panel of the Sun Fire X4500 server is illustrated in Figure 10. Features
accessible from the back of the system include:
• Redundant hot-swap power supplies
• 10 Gb Ethernet port (on PCI card, not shown)
• Graphics port
• Network and serial management ports to the ILOM system controller
• Four USB ports, two in front and two in the rear of the chassis
• Four auto-sensing 10/100/1000 BaseT Ethernet ports (RJ-45)
Redundant, hot-swap power supplies
10 Gb Ethernet card
(not shown) 4 10/100/1000 BaseT Ethernet pots
2 USB ports
Graphics and ILOM card
Serial management port
Figure 10. Rear view of the Sun Fire X4500 server
The Sun Fire X4500 server employs Serial ATA II (SATA II) technology for its 48 internal
disk drives. SATA II technology is rapidly approaching other disk drive technologies in
the prime storage tier, offering features such as device hot-swap compliance and power
management compliance. In particular, unlike technologies such as Fiber Channel
Arbitrated Loop (FCAL) and shared SCSI, SATA II’s point-to-point architecture is ideal for
serving video streams since it reserves dedicated bandwidth to each attached device.
17 Sun Streaming System Architecture Sun Microsystems, Inc.
As discussed, each Sun Fire X4500 server features six SATA II storage controllers, each
utilizing a full PCI-X 133 MHz @1.06 GBps bus. The full complement of 48 hot-pluggable
3.5inch SATA hard disk drives provides a total capacity of 24 terabytes with
approximately 2 GB/second disk-to-memory throughput and 1 GB/second disk-to-
In the Sun Streaming System, Sun Fire X4500 servers boot remotely from a central
Supervisor node, reserving all 48 disk drives for storing video streams. Each Sun Fire
X4500 server is conﬁgured as 12 RAID 5 arrays (3 + 1). This redundancy conﬁguration
dictates that 75 percent of the storage capacity is available for video data storage.
Sun Fire x64 servers
Open and standard Sun Streaming Software provides control elements of the Sun
Streaming System in a scalable, fault-tolerant, and distributed fashion. Sun Streaming
Software runs on standard Sun x64 servers, including the Sun Fire X4100 server
(Figure 11), as well as the Sun Fire X4500 servers and Sun Fire X4950 Streaming
Switches that make a Sun Streaming System conﬁguration. Different software nodes
that comprise the software architecture are described in Chapter 3.
Sun Fire X4200 M2 server
Sun Fire X4100 server
Figure 11. The Sun Fire X4100 server runs Sun Streaming Software components in addition to Sun Fire
X4500 servers and Sun Fire X4950 Streaming Switches
Based on powerful AMD Opteron processors, these systems provide high performance,
large memory support, and a balanced design to help ensure scalability and
performance. The 1U Sun Fire X4100 and X4100 M2 servers support two AMD Opteron
processors, up to 32 GB of memory and 2 PCI-X slots. For more technical information on
the Sun Fire X4100 server, please visit sun.com/x64.
All components of the Sun Streaming System, including Sun Fire X4100 servers, Sun Fire
X4950 Streaming Switches and Sun Fire X4500 servers boot remotely from the
Supervisor node, a special-purpose node that is responsible for centralized
management and control of the Sun Streaming System.
Network switching and conﬁguration
Even though it is composed of multiple individual systems, the Sun Streaming System
functions as an integral system. The nodes are interconnected using a Gigabit Ethernet
switch with two VLANs.
18 Sun Streaming System Architecture Sun Microsystems, Inc.
Two separate VLANs are provided containing separate subnets:
• The internal subnet enables network remote booting of all Sun Streaming System
servers from the Supervisor node. The internal subnet also carries control and data
trafﬁc between the various Sun Streaming Software nodes.
• The external subnet carries trafﬁc between the Sun Streaming System and non-
streaming back-end servers such as the Content Server, Billing Server, etc. The
external subnet also carries control information consisting of real time streaming
protocol (RTSP) from the client set top boxes that are connected to the system.
The unidirectional streaming network that takes video streams from the Sun Fire X4950
Streaming Switch to the carrier network and on to the set top box is entirely separate
from the internal and external Gb Ethernet networks (Figure 12).
External Network Sun Streaming System
(User Defined: Internal Network
Set Top Boxes, etc.)
Figure 12. The Sun Streaming System is conﬁgured with internal and external subnets conﬁgured as
VLANs, and delivers unidirectional video to set-top boxes
19 Sun Streaming Software Architecture Sun Microsystems, Inc.
Sun Streaming Software Architecture
Beyond serving individual streams, service providers need to be able to scale and
expand their IP video services without artiﬁcial and arbitrary proprietary limitations. To
help ensure interoperability, scalability, and ﬂexibility, the Sun Streaming System
employs an open systems approach to both software architecture and management.
This approach provides distinct advantages, including:
• A single point of control for the entire Sun Streaming System
• Integration with key third-party components
• Multi-dimensional scalability through replication of Sun Streaming Software
• Failover and recovery through software component redundancy
The sections that follow describe key Sun Streaming Software software components
along with management and failure recovery highlights.
Software components and architecture overview
Sun Streaming Software provides the key services that are required to import and
transmit video streams, as well as services to manage the system as a single entity.
These software nodes can be replicated to add ﬁne-grained scalability for additional
capacity of individual functions, and to provide for failover in the case of software or
hardware failure. Figure 13 illustrates the principal software components along with
the open standard interfaces that they provide.
CLI, SNMP, Supervisor
RTSP Session Controller
Sun Streaming System
CORBA Content Controller Internal Control Network
FTP or UDP Import Pre-Processor
Import Pre-Processor Media Store
Media Store Streaming Service
MPEG2, H.264 node
node TCP/IP node
node UDP/IP node
Figure 13. The Sun Streaming System software architecture is based on open-systems protocols
The Supervisor node runs on a Sun Fire X4100 server (or two for redundancy) and
functions as the central point for monitoring and controlling the entire Sun Streaming
System, and also serves as a boot server for all of the other Sun Streaming Software
20 Sun Streaming Software Architecture Sun Microsystems, Inc.
nodes. Disk boot images for all other systems reside and are managed on the
As the centralized operation and control system, the Supervisor node presents the
external management interface to the Sun Streaming System, interacting with user
interface agents such as the command line interface (CLI) and Web interfaces. Simple
Network Management Protocol (SNMP) support is also provided. The Supervisor node
coordinates the initialization of the system, monitors the state of other nodes, and
relays logging messages.
Session Controller nodes
One or more Session Controller nodes run on individual Sun Fire X4100 servers. Session
Controller nodes manage the establishment of sessions for streaming within the the
Sun Streaming System. The Session Controller communicates with the third-party
components such as the Session Resource Manager (SRM) and set top boxes (STBs)
using the real time streaming protocol (RTSP). The Session Controller also controls the
Streaming Service node (described below) when trick-play requests are received from
individual set-top boxes.
Content Controller nodes
Running on one or more Sun Fire X4100 servers, Content Controller nodes allow a third-
party asset management system to load and unload VoD or nPVR assets. Prior to
allowing the operation, the content controller veriﬁes that sufﬁcient bandwidth exists
on an Import Pre-Processor node to begin the import process, and that sufﬁcient disk
space remains on a Sun Fire X4500 server (Media Store node) to store the content.
Import Pre-Processor nodes
One or more Import Pre-Processor nodes (on one or more Sun Fire X4100 servers)
process MPEG2 or H.264/AVC video streams before they are stored on a Sun Fire X4500
server (Media Store node). VoD content is imported from FTP servers while nPVR
content is imported from encoders. The Import Pre-Processor node generates trick-play
ﬁles and optimizes the structure of the video for disk I/O and packet transmittals. The
fast-forward and rewind speeds of the trick-play ﬁles are conﬁgurable, and there is no
limitation on the number of trick-play speeds that can be conﬁgured.
Media Store nodes
One Media Store node runs on each Sun Fire X4500 server in the Sun Streaming System.
This software interface allows access to the considerable storage resources and
throughput of the Sun Fire X4500 server. Up to 32 Sun Fire X4500 servers can be
deployed in a single Sun Streaming System conﬁguration. Running directly on the Sun
21 Sun Streaming Software Architecture Sun Microsystems, Inc.
Fire X4500 server, the Media Store node manages the scheduling of block reading and
writing to and from the RAID disks. Blocks are then transmitted to Streaming Service
nodes for streaming. Since Media Store nodes also boot remotely from the Supervisor
node over the internal network, no local disks are required for boot and local ﬁle
system support. As a result, the entire disk capacity of each Sun Fire X4500 server (24
terabytes) is available for storing video content.
One Streaming Service node runs on each Sun Fire X4950 Streaming Switch. Multiple
Streaming Service nodes can be deployed in a given Sun Streaming System
conﬁguration. As discussed, the Streaming Service nodes interact with Media Store
nodes to fetch the streaming content from storage. The Streaming Service node also
manages the Sun Fire X4950 Streaming Switch video cache and schedules packet
stream transmission to prevent conﬂicts in the streaming engine. Streaming Service
nodes act upon receiving control commands from Session Controller nodes.
Sun Streaming System management
Just as the Sun Streaming System is designed to function as single entity, it is likewise
managed as a single carrier-grade system. This approach reduces complexity and saves
administrative expenses over multiple highly-distributed video server platforms.
Speciﬁcally, the Sun Streaming System is designed to be managed in a geographically
dispersed network from one or more network operation centers (NOCs). The
management capabilities of the system enable administrators to:
• Detect problems before downtime is experienced
• Find root cause problems rapidly when a device fails
• Manage the system with a minimum of staff
• Collect trending data for performance analysis
The Sun Streaming System offers three ways to manage the system:
• A full-featured command line interface (CLI) provides conﬁguration management
capabilities consistent with other carrier-grade equipment.
• SNMP support is provided to help operators manage multiple Sun Streaming Systems
from a centralized NOC, and is primarily used for fault and performance
• An intuitive and easy-to-learn Web interface is also provided (Figure 14).
22 Sun Streaming Software Architecture Sun Microsystems, Inc.
Figure 14. The Sun Streaming System GUI provides remote administrative access
from a Web-based interface
The command line interface (CLI) offers a convenient method for conﬁguration
management, and it allows the entire system to be managed from a single interface.
Automation typically required in carrier environments is easily accomplished using the
robust CLI. This approach provides a number of advantages, including:
• No need to log into different applications or nodes
• No need to set conﬁguration ﬁles on multiple machines
• No need to monitor multiple nodes
• The ability to detect and prevent syntax and semantic errors
• Control over resource utilization
• The ability to gracefully add and remove nodes
• Redundancy mechanisms
The CLI uses a hierarchical access model, where commands are used to move between
the levels with the system prompt identifying the current level. Each level of the
hierarchy allows access to different functionality.
• The User access mode is the top-level access mode in the hierarchy, allowing
execution of all show commands.
• Enable mode allows the administrator to access all show commands as well as
management conﬁguration commands that do not affect the system conﬁguration.
• Configuration mode provides access to all commands and command modes to
conﬁgure all aspects of the system.
23 Sun Streaming Software Architecture Sun Microsystems, Inc.
Failure detection and recovery
The Sun Streaming System provides high availability through replication of individual
network components such as Sun Fire X4100 servers, Sun Fire X4500 servers, and the
Sun Fire X4950 Streaming Switch itself. In addition, individual Sun Streaming System
servers feature redundant components that provide for high availability and the
scheduling of downtime for necessary repairs. Figure 15 illustrates a redundant
conﬁguration of both Sun Fire X4500 servers and Sun Fire X4950 Streaming Switches,
allowing quick recovery in the event of failure.
Sun Fire X4950
Redundant Streaming Switches
Sun Fire X4500
10/1 GB Ethernet
Sun Fire X4100
Figure 15. High availability Sun Streaming System conﬁgurations can be achieved by replicating
State and fault management
The Sun Streaming Systems allows software services to be added or removed while a
system is operational. This ﬂexibility is accomplished by changing the state of individual
nodes. All Sun Streaming System nodes have the basic capability to report their state
(enabled, disabled, or failed) and all nodes can indicate when a fault has been
detected. Operator messages can be directed to a log ﬁle, the command line interface
(CLI), or information can be communicated via SNMP through traps and other
Sun Fire X4500 server protection and redundancy
With RAID 5 support on each of 12 disk banks, the Sun Fire X4500 server is designed to
allow disks to “fail in place”, yielding high availability of video content. At the same
time, The highest level of protection results when content is replicated in at least one
24 Sun Streaming Software Architecture Sun Microsystems, Inc.
other Sun Fire X4500 server for failure protection. Redundant Sun Fire X4500 servers
protect against all failure cases in either disks, networks, or other individual system
The Sun Fire X4500 server is designed to protect against disk failure. With individual
disk banks covered by RAID software, the Sun Fire X4500 server can handle multiple
individual disk failures (one per bank). Once a disk in given bank fails, that bank
continues to operate but is placed into “degraded” mode until the disk is replaced and
the RAID bank is reconstructed.
Two or more disk failures in a given RAID bank constitute failure for the Sun Fire X4500
server, and at that point the content on the MediaStore node is considered invalid.
Content must then be made available from another MediaStore node or data must be
retrieved from an archival system.
Sun Fire X4950 Streaming Switch redundancy
Replication of Sun Fire X4950 Streaming Switches is recommended to allow for high
availability and seamless failover. In a redundant conﬁguration, both Sun Fire X4950
Streaming Switches listen to updates in promiscuous mode, but an internal attribute
determines which switch is set to streaming mode, with the other set to standby mode.
Each StreamingService node honors all play requests, but the switch in standby mode
has its streaming output disabled.
The Supervisor node monitors the health of each StreamingService node. When the
Supervisor node determines that one Sun Fire X4950 Streaming Switch or
StreamingService node has failed, it changes the state of the backup StreamingService
node to Streaming mode and output commences. Because the video segments are
already in DRAM on the backup switch, the failover is transparent and no video streams
Supervisor node redundancy
For high availability, the Supervisor node can also be replicated in a Sun Streaming
System conﬁguration. In a system with two Supervisor nodes, one is considered the
primary node with the other named as backup. An election protocol ensures that there
is only one primary Supervisor node. Supervisor nodes implement monitoring objects to
detect when a node has failed and the backup node must become the primary node.
25 Sun Streaming Software Architecture Sun Microsystems, Inc.
Redundancy for other Sun Streaming Software nodes
Other Sun Streaming Software nodes can also be replicated, either for capacity
purposes, or for high availability.
• Each Import Pre-Processor node can import up to 100 Mbps of video. VoD import is
considered a non-critical event and a spare available server may be sufﬁcient in case
of hardware failure. NPVR import is critical due to the time-critical nature of linear
video feeds. The nPVR content import model should be to duplicate content import
to survive node failure.
• The Content Controller node typically does not need to be rated for high load, and the
redundancy scheme should be in line with the VoD or nPVR schemes mentioned
• The Session Controller is critical for the delivery of video so at least one redundant
node should be provided in case of a software or hardware failure. The spare node is
treated as a hot standby. Each Session Controller node can handle 2,500
simultaneous session requests per second.
26 The Sun Streaming System in Context Sun Microsystems, Inc.
The Sun Streaming System in Context
By their nature, IPTV deployments can be large and complex, and integration can
ultimately be one of the most complex and time-consuming tasks for an organization
deploying an IPTV solution. Components from a wide variety of vendors must be made
to work together as a part of a uniﬁed system that presents a high quality of service to
the subscriber. Communications must take place not only between components of the
new systems, but with legacy systems such as billing.
The Sun Streaming System and its integral hardware and software components work in
the context of and end-to-end video delivery system. However, more than just providing
a video server component, Sun has committed signiﬁcant resources to integrate with a
variety of third-party hardware and software providers. By supporting open and
standard interfaces and testing with key third-party component providers, the Sun
Streaming System takes much of the time and complexity out of deploying IPTV
services. The result is IPTV infrastructure that can be deployed more quickly, reducing
time to service for providers.
Integrated third-party components
Figure 16 illustrates how the Sun Streaming System ﬁts within an end-to-end video
delivery system. This perspective is a representative architecture for illustration
purposes only. The Sun Video Streaming System can be deployed in other architectures
Billing System/CRM Ad Placement Server
Subscriber Management System Video
Session Resource Management
EPG Ingest Broadcast Content Manager Navigation Server
Live TV STB
Asset Manager STB
Management Console (HTML)
Sun Streaming System
Figure 16. The Sun Streaming System in the context of an end-to-end video services infrastructure
27 The Sun Streaming System in Context Sun Microsystems, Inc.
The Sun Streaming System interfaces with a number of third-party components in an
end-to-end conﬁguration, including:
• Broadcast Content Manager — The Broadcast Content Manager (BCM) collects,
formats, and distributes Electronic Program Guide (EPG) information for use in
delivering Sun Streaming System nPVR services.
• Navigation Server — The Navigation Server coupled with the Navigator client
running on the set top box manage the video experience and service to the
subscriber. The Navigation Server provides nPVR and VoD data to the Navigator client.
• Asset Management System — The Asset Manager is responsible for the full lifecycle
management of on-demand content and associated services. The Asset Manager
manages content ﬂow, including import, distribution, and delivery. The Asset
Manager accepts VoD content packages and manages their provisioning into the Sun
Streaming System, distributing content and metadata as appropriate, and providing
veriﬁcation capabilities for imported content.
• Subscriber and Session Systems — The Subscriber and Session Systems include the
Subscriber Management Server, the Entitlement and Offer Server, and the Session
Resource Manager (SRM). The Subscriber Management system enables provisioning,
veriﬁcation, and reporting of customer data, driving the following tasks:
– Entitlement veriﬁcation
– Offer up-sell and add-on services by verifying subscriber account information
– Accurate reporting of requested services
– Providing accurate billing for digital services via interfaces to the Billing Sys-
• Electronic Programming Guide — The Electronic Program Guide import capability
accepts broadcast schedule information from aggregators and providers, validating it
and allowing it to be edited if necessary. Unique identiﬁers can be assigned to
broadcast events for nPVR usage.
• Digital Rights Management (DRM) / Conditional Access System (CAS) — The
Conditional Access System (CAS) protects access to content by managing access to
the keys required to decrypt streamed content. Responsibilities include
authentication, key management, key distribution/enablement, database and
logging, and certiﬁcate authority management.
• Billing System/Customer Resource Management (CRM) — Billing System
interactions are transparent to the Sun Streaming System, taking place through the
Subscriber Management System or Entitlement Server.
• Ad Placement Server — The Ad Placement Server identiﬁes ads suitable for inclusion
in unicast streaming sessions and coordinates with asset management to maintain
an up-to-date inventory of provisioned ads.
• Encoders — Encoders enable data/video encryption prior to video transport to the
Sun Streaming System system. Video transport is handled by using UDP or FTP. The
encrypter may have distinct implementations or operating modes for real-time
28 The Sun Streaming System in Context Sun Microsystems, Inc.
encryption (e.g. for broadcast feeds) and stored-content encryption (e.g. for VoD and
advertisement asset import).
• Set top boxes — Set top boxes from multiple vendors are supported by the Sun
Streaming System. Set top boxes communicate with the Sun Streaming System by
receiving streams over UDP/IP and using the real time streaming protocol (RSTP) over
TCP/IP for control.
For a complete and up-to-date list of the third-party components that work with the
Sun Streaming System systems, please see the website at
Sun Streaming System interactions with third party
As a part of understanding how the Sun Streaming System ﬁts into video services
infrastructure, it is helpful to consider how the system interacts with other key software
and hardware components. The sections that follow detail key interactions. To
reiterate, this is one possible architectural representation. The Sun Streaming System
can work within other architectures as well.
Navigation Server: managing the user experience
Given the high level of expectations for quality of service from video services customers,
the user experience is one of the most important parts of any IPTV system. These
components can also be some of the most expensive. Figure 17 illustrates the
interaction of the Navigation Server with other key components.
(Cablelabs 1.1) Navigate
Record, User Profiles,
Delete Buy, Get Token,
Broadcast Entitlement Record, Delete
Figure 17. Navigation Server interaction
Offering integration with a content Navigation Server is key to Sun’s strategy to evolve
content delivery to a complete unicast model. When properly implemented, the
Navigation server can help to remove the distinction between broadcast and on-
demand content. The Navigation Server interfaces to both kinds of content, making the
content available to the applications running on the set top box in a uniﬁed manner.
29 The Sun Streaming System in Context Sun Microsystems, Inc.
The set top box runs a multimedia home platform (MHP) software stack, enabling the
subscriber to perform a wide variety of actions through application software such as
that based on Java™ technology. The integration of the set top box and the Navigation
Server support personalizing the subscriber experience, acting as a gateway between
the set top box and the Entitlement Server, through which purchasing and
authorization are transacted.
The Navigation Server is also the component that brings together the data required to
implement networked personal video recording (nPVR) functionality. With this
capability, record and delete requests from subscribers are communicated to the
Broadcast Content Manager which then schedules record and delete actions into the
Sun Streaming System.
Broadcast Content Manager: control nPVR assets
In addition to managing storage and deletion of nPVR content, the Broadcast Content
Manager also is responsible for providing the electronic programming guide (EPG)
content to the Navigation Server for transmission to the subscriber.
The Broadcast Content Manager receives information from the EPG, describing what
programs are broadcast when, and uses that information to control recording. It also
receives information from the Navigation Server regarding programs that subscribers
have already recorded, and can schedule deletion of content that no longer needs to be
retained on the system. Figure 18 illustrates the integration of the Broadcast Content
Manager with EPG import, the Navigation Server, and the Sun Streaming System
EPG Metadata EPG Metadata
(TVA or XML-TV) Broadcast (TVA or XML-TV)
Ingest Asset/Event Record, Delete Server
Figure 18. Broadcast Content Manager
The Entitlement Server acts as a gatekeeper, interfacing with the billing system to
make sure that only purchased and approved content is sent out to the set top box.
Subscriber data is obtained from the billing system, and subscriber purchasing data is
provided back to the billing system.
30 The Sun Streaming System in Context Sun Microsystems, Inc.
The Entitlement Server participates in two main transactions. Content purchases are
initiated by the Navigation Server with the Entitlement server responding with a token
once the transaction completes successfully. The Entitlement Server is also involved in
playlist resolution, which happens after the purchase, when the subscriber issues a play
request for a given video stream (Figure 19).
Check Token, Buy,
Get Playlist Get Token
Figure 19. Entitlement Server interaction
Streaming is the ultimate result of a successful purchase and/or a successful request to
play a stream. The Session Controller node is ultimately the central component in
stream control, and it interacts with three components:
• The set top box is the originator of requests, and the ultimate consumer of video
• The Session Resource Manager (SRM) checks the token and returns the playlist
• Streaming Service nodes do the actual streaming out to the set top box
If a key is required for encrypted content, the set top box retrieves the key from the
Conditional Access System. Figure 20 illustrates the streaming interaction.
Check Token, Get Playlist
Controller Get Key
Stream Playlist STB
Service UDP: Video
Figure 20. Streaming interaction between the Sun Streaming System and third-party components
31 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
Deploying the Sun Streaming System for IPTV
Unlike traditional video servers, the Sun Streaming System can take direct advantage of
existing dark ﬁber for unidirectional video delivery. By facilitating consolidated (rather
than broadly distributed) video distribution, the Sun Streaming System can simplify
infrastructure, and lower costs while enhancing reliability for video stream delivery. The
sections that follow describe the Sun Streaming System in the context of physical
network infrastructure, and also provide an example conﬁguration.
Video distribution considerations
One of the key questions in deploying IPTV infrastructure is whether to provide
consolidated or unconsolidated video services, or indeed a hybrid implementation that
combines the two. These choices present a number of trade-offs.
• Unconsolidated video distribution
For small markets with minimal initial demand, unconsolidated video distribution
may seem attractive. This approach places video server systems close to the edge
of the network, lowers initial costs for small deployments, and minimizes trafﬁc
over the backbone network while not depending on ﬁber availability between the
core and the edge of the network.
Unfortunately, this distribution scheme means that content is duplicated in a
greater number of sites. In addition, both capital and operational expenses
increase more rapidly as the number of subscribers increase. An unconsolidated
approach also requires more staff and more spare parts over the project lifetime,
and those resources are typically distributed over a larger geographic area.
• Consolidated video distribution
The availability of dark ﬁber in many networks makes consolidated video
distribution an attractive proposition for many service providers. With the Sun
Streaming System able to provide massive multi-dimensional scalability, a
consolidated approach is considerably more feasible.
A consolidated approach leverages the point-to-multipoint ﬂow of video trafﬁc
implicit in most network implementations and provides the lowest capital and
operational expenses over the lifetime of the project. With video head-end
functions managed centrally, a consolidated approach also requires the lowest
number of staff for ongoing operations and the lowest number of spare parts. A
consolidated and centralized approach can also provide higher reliability by
having fewer components that can fail. Having a smaller number of centralized
video servers also makes it easier to deploy new services such as nPVR. For
example, the even if 100 subscribers record the same show or movie, a centralized
Sun Streaming System would only need to store a single copy of the video.
32 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
Components of the Sun Streaming System may be appropriate in a range of
consolidated, unconsolidated, and hybrid conﬁgurations. Given the strengths and
scalability of the Sun Streaming System, this discussion will focus on consolidated
The Sun Streaming System in a headend or video hub ofﬁce
Figure 21 illustrates the Sun Streaming System components deployed in a headend
or Video Hub Ofﬁce (VHO) as a part of a consolidated distribution network.
Figure 21. The Sun Streaming System components in a centralized headend context
The illustration is annotated as follows:
1. Multiple Sun x64 servers act as Sun Streaming Software nodes. Each server has a
gigabit Ethernet port for internal VLAN communication within the Sun Streaming
System, and a gigabit Ethernet port attached to the external network.
2. Multiple Sun Fire X4500 servers can be deployed as a part of the Sun Streaming
System. Content is imported from the Sun Fire X4100 servers. Video is then fed to a
Sun Fire X4950 Streaming Switch from an integrated 10 Gb Ethernet connection
between the Sun Fire X4500 server and the switch.
3. Each Sun Fire X4950 Streaming Switch has 32 10 Gb Ethernet ports, letting it trans-
mit up to 80,000 streams at 4 Mbps. Sun Fire X4950 Streaming Switches include
integrated XFP modules capable of transmitting up to 40 km over ﬁber.
4. An optional passive optical multiplexer can be used to combine multiple wave-
lengths over a single ﬁber.
5. The Sun Streaming System leverages ﬁber infrastructure. Trafﬁc can be transmit-
ted on dark ﬁber, or terminated on a CWDM or DWDM multiplexer.
33 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
6. In the central ofﬁce, another passive optical multiplexer can be used to demulti-
plex wavelengths and terminate them on 10 Gb Ethernet switches.
7. Low cost 10 Gb Ethernet to 1 Gb Ethernet switches are available for terminating
video streams. These switches usually have QoS capabilities, and appropriate prior-
ities can be assigned to VoIP and video trafﬁc.
8. Video trafﬁc is transparent to edge routers. Routers use QoS functionality to give
priority to VoIP trafﬁc.
9. A VoIP gateway connects to a distribution router and sends packetized voice trafﬁc
to the legacy voice network. This activity is invisible to the Sun Streaming System.
10. A DSLAM or QAM is located either in the central ofﬁce or in a remote location. Mul-
tiple 1 Gb Ethernet ports are trunked together for uplink to the switch.
Sun Streaming System design example
Full scoping, design, and sizing of the Sun Streaming System is beyond the scope of this
document. However, it is helpful to work through an example to understand some
rough criteria for the Sun Streaming System design. This process involves:
• Understanding and forecasting relevant key objectives
• Translating these objectives into storage and streaming requirements
• Designing a system to meet those requirements
Collecting key information
Designing a Sun Streaming System conﬁguration system involves collecting key data
and answering questions about the types and quantities of video data that are
anticipated. Key questions include:
• At what bit rate will standard deﬁnition (SD) and high deﬁnition (HD) video be
• How many hours of SD and HD content needs to be stored for VoD?
• What is the total number of subscribers?
• How many of them are expected to concurrently watch VoD?
• How many linear TV channels will be imported for nPVR?
Case study: a hypothetical VoD and nPVR system
For the purposes of example, Table 1 includes three years of projected data for a video
system to serve both standard deﬁnition and high deﬁnition streams to both VoD and
34 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
Table 1. Requirements over three years for a hypothetical VoD and nPVR system
Assumptions Year 1 Year 2 Year 3
Standard deﬁnition bit rate 2 Mb/s 2 Mb/s 2 Mb/s
High deﬁnition bit rate 8 Mb/s 8 Mb/s 8 Mb/s
Hours of SD VoD content 2,000 4,000 6,000
Hours of HD VoD content 1,000 2,000 3,000
Total subscribers 10,000 20,000 30,000
Peak concurrent VoD viewers (%) 10% 10% 10%
Percent of SD set top boxes 50% 50% 50%
Percent of HD set top boxes 50% 50% 50%
Simultaneous VoD import (titles) 1 1 1
Linear TV channels (SD) 100 100 100
Linear TV channels (HD) 20 30 40
nPVR subscription rate 30% 35% 40%
Peak concurrent nPVR viewers (%) 50% 50% 50%
Mean nPVR storage used per subscriber 20 30 40
Simultaneous session and trick-pay 10% 10% 10%
requests (% subs per second)
Table 2 provides a synthesis of these requirements
Table 2. Requirements synthesis for hypothetical system, years 1-3
Requirements Year 1 Year 2 Year 3
Peak concurrent VoD viewers 1,000 2,000 3,000
nPVR subscribers 3,000 7,000 12,000
Peak concurrent nPVR viewers 1,500 3,500 6,000
Peak VoD streaming requirement 5 Gbps 10 Gbps 15 Gbps
Peak nPVR streaming requirement 8 Gbps 18 Gbps 30 Gbps
VoD + nPVR streaming requirement 13 Gbps 28 Gbps 45 Gbps
VoD storage requirements 11 terabytes 22 terabytes 32 terabytes
nPVR storage requirements 120 terabytes 420 terabytes 960 terabytes
VoD + nPVR storage requirements 131 terabytes 442 terabytes 992 terabytes
Peak import capacity 368 Gbps 448 Gbps 528 Gbps
Storage overhead estimate (x multiplier) 2 2 2
Session setup/teardown/trick-play 250 per second 550 per second 900 per second
The requirements expressed in the tables above provide sufﬁcient information to build
a Sun Streaming System conﬁguration. Only the ﬁrst year will be considered in this
analysis but additional Sun Streaming System components can be easily added as
forecast, or as demand dictates. Organizations can choose to deploy redundant
35 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
components for greater availability and failover. Both non-redundant and redundant
numbers are provided in the sections below.
• Storage requirements
In year 1, the combination of VoD plus nPVR storage is expected to require 131
terabytes. With each Sun Fire X4500 server supporting 24 terabytes, this
requirement translates to:
– Non-redundant: six Sun Fire X4500 servers
– Redundant: 12 Sun Fire X4500 servers
• Streaming capacity
The analysis ﬁxed the streaming capacity for VoD plus nPVR streams at 13 Gbps.
Each line card has 40 Gbps of streaming capacity so a single line card should
sufﬁce to serve the necessary capacity. However, the redundant storage
requirements described above require 12 10 Gb Ethernet connections for
connecting to Sun Fire X4500 servers. In addition, Line Cards are provided only in
increments of 1, 2, 4, or 8. Therefore the Sun Fire X4950 Streaming Switch
– Non-redundant: One Sun Fire X4950 Streaming Switch chassis, four Line Cards,
one Optical Card, one Controller Card
– Redundant: Two Sun Fire X4950 Streaming Switch chassis, eight Line Cards, two
Optical Cards, and one Controller Card
• Import capacity
The peak import capacity requirement for this example is 368 Gbps. Since each
ImportProcessor node can handle 100 Gbps, the requirements are:
– Non-redundant: Four Input Pre-Processor nodes
– Redundant: Eight Input Pre-Processor nodes
• Other Sun Streaming Software nodes
Other Sun Streaming Software nodes need only be provided in singular quantities
unless a dual-redundant conﬁguration is desired for availability:
– Non-redundant: One Supervisor node, one Content Controller node, one Session
– Redundant: Two Supervisor nodes, two Content Controller nodes, two Session
36 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc.
Figure 22 graphically illustrates the results of the year-1 analysis. These Sun Streaming
System components could easily be accommodated in three 42U racks.
20-30 Gb/Fast Ethernet
2 Sun Fire X4950 2-16 10/1 GB
Streaming Switches Ethernet
12 Sun Fire X4500
Control Traffic STB
14 Sun Fire X4100
Figure 22. Logical block diagram of hypothetical VoD and nPVR conﬁguration for year one of the
A further projection of the the Sun Streaming System components required for the ﬁrst
three years is provided in Table 3.
Table 3. Sun Streaming System components for a hypothetical 3-year VoD and nPVR deployment
System Components Year 1 Year 2 Year 3
Sun Fire X4500 servers with 12 38 84
48 500 GB drives
Sun Fire X4950 Streaming Switch 2 4 6
chassis with one Controller Card
Line Cards 8 20 96
Optical Cards 2 6 12
Supervisor nodes 2 4 6
Import Pre-Processor nodes 8 10 12
Content Controller nodes 2 2 2
Session Controller nodes 2 2 2