ContentsSRINI:----------------------------------------------------------------------------------------------------------------------3

INTRODUCTION-------------------------------------------------------------------------------------------------------4

WHAT IS DLNA?-------------------------------------------------------------------------------------------------------5

So what?--------------------------------------------------------------------------------------------5New bridges----------------------------------------------------------------------------------------6Treasure chest-------------------------------------------------------------------------------------7

WHY DLNA?-------------------------------------------------------------------------------------------------------------9

VEER:--------------------------------------------------------------------------------------------------------------------11

TECHNICAL VIEW OF A DLNA NETWORK-----------------------------------------------------------------12

NETWORKING AND CONNECTIVITY:-----------------------------------------------------------------------13

DLNA SYSTEM ARCHITECTURE-------------------------------------------------------------------------------14

Pull-type architecture---------------------------------------------------------------------------14Push-type architecture--------------------------------------------------------------------------15

DEVICE DISCOVERY:----------------------------------------------------------------------------------------------18

SUDEE:------------------------------------------------------------------------------------------------------------------19

COMMON MEDIA FORMATS :----------------------------------------------------------------------------------20

QUALITY OF SERVICE (QOS):----------------------------------------------------------------------------------21

AUTHENTICATION AND AUTHORIZATION:--------------------------------------------------------------22

DIGITAL RIGHTS MANAGEMENT:----------------------------------------------------------------------------23

USE CASES-------------------------------------------------------------------------------------------------------------24

CONCLUSION:--------------------------------------------------------------------------------------------------------25

WHAT CAN WE SAY ABOUT DLNA?--------------------------------------------------------------------------27

1

2

Srini:

3

Introduction

DLNA is an acronym for Digital Living Network Alliance. It is a capability in a device allowing it to talk to other devices with similar DLNA capability. It interconnects electronic devices within a zone.

Let us examine a few simple use-cases which have paved way to the development of DLNA. It’s nice to click away pictures on a vacation - loads and loads of them; viewing them back on a big screen is when the lazy you gets in. A lot of cables running here and there, match the red wire to the red slot and the yellow wire to the yellow slot. Uhh! Aren’t you often contented seeing the pictures on your camera's small screen? A good old friend drops in home and you are all excited to share your collage day pictures with him. You take the camera and connect it to the new stunning Plasma TV. As you sit thro', you recollect a few old photos of your school union and wish to see them immediately on the same screen. You see, they are on your laptop. You have to bring the laptop all the way, connect it to the TV or copy images to a card and plug in the card to the TV. Aint it cumbersome? An evening on a tiring day, you wish to watch your favourite serial lying on the couch in the living room. The serial is left recorded in the DVR in the bedroom. You have to either push yourself hard to the other room a floor away or you rather chuck the TV show and lie lazily on the couch cursing everything you could think of. DLNA is one stop for all such user scenarios.  

4

What is DLNA?

DLNA is a standard based on UPnP model, whose primitive goal was to attach all devices directly to computer. Earlier there was only one device which was considered capable of handling all sorts of computing and that was “computer”. With advancement in technology, we have intelligence embedded in everything that we use, making every device a micro - computer in its own.

With a view to interconnect devices seamlessly, DLNA was brought to light. DLNA represents the content negotiation and sharing portion.

At a customary level, a DLNA device works like any other device by discovering other DLNA-enabled hosts. But its competence doesn’t stop there. The DLNA device goes on to learn other devices’ capabilities. Through DLNA, a media server can be located and then summoned to play or display a stored family photo, movie, music file, etc.

-------------------/* Only for ref- rephrase */------------------

Think of a DLNA server as a multi-room digital video recorder (DVR) on steroids. Moreover, it's one that a subscriber can buy in interchangeable devices from a host of vendors. In fact, DLNA's second specification (v1.5), released in late 2005, defines 10 new device classes.

In the future, as DLNA's technical capability and vocabulary expand, the spec will add digital media printing and the ability to push images to a network attached storage (NAS) device, manage media with a mobile device, and leverage quality of service (QoS) between devices. Already, however, a consumer who purchases, say, a DLNA-certified Blu-ray Disc (BD) player and exposes it to a home media server can easily switch between a high definition (HD) movie and some other media accessible over a home network.

So what?

For decades, CE devices haven't worked together, so why should that change now? For one, it's already changing. Consider the high-definition multimedia interface (HDMI). (See the May 2007 issue of Communications Technology for more on HDMI.) Before HDMI, each manufacturer developed its own proprietary cables and signaling (e.g., Panasonic's HDAVI and Pioneer's SR) that none could ever agree upon.

With DLNA, the CE industry is working together again, using standard networking

5

(Ethernet) and requiring interoperability testing to use the DLNA logo. Using Ethernet allows CE manufacturers to build upon existing standards, silicon and know-how to enable rapid development

DLNA's vocabulary and installed base should expand dramatically in the coming years because of the rising interest in networking CE devices in the home, especially because DLNA is a desirable feature of any new CE device that hosts either an Ethernet jack or has built-in Wi-Fi.That makes it something that cable operators - and broadband service providers of all stripes - will put on their near-term radar.

Just as operators have increased the number of programming choices and on-demand and interactive options, they can also help expand and extend DLNA to increase consumer choices. Together, DLNA and UPnP provide a nest of interoperable and inter-accessible technology within each networked home, essentially creating a desirable island of rich media functionality within the home.

New bridges

The types of bridges that are possible with DLNA, however, may differ significantly from legacy bridge offerings.

Today's video, wireless, voice, and even Internet services all maintain a fairly significant data center management component that requires integration above the data center to bridge features of one service to another. The conventionally understood way to bridge these services requires a physical technology bridge, such as IP Multimedia Subsystem (IMS), to connect one service to another; an operations/business support system (OSS/BSS) bridge to package, activate and bill for these services; and finally, one or more service-specific communications bridge(s) for various service elements to communicate with each other to produce the desired functionality (while preferably not interfering with another service).

This process ends up being rather complicated and formalized, which is why you don't see cross-service functionality rapidly flowing out of service provider development shops.

The bridging of DLNA devices, however, is "opportunity based" in that it merely requires the presence of two or more DLNA capable devices on a home network. Those devices could include telephones, fax machines, home security systems, TV sets, stereos, set-top boxes, along with more traditionally networked devices such as computers.

The scope of possible devices could make DLNA appear as something of a threat, the flexing of CE manufacturers' muscles to show that bridging services can just as easily happen within the home as in the data center. It also could

6

reduce the bridging-role of service-provider equipment such as the set-top box or modem. Perhaps more importantly, once networked, other DLNA devices could bridge this network of devices to other Internet-based services, such as I-Tunes, MovieLink and others.

As service providers of all stripes place DLNA equipment in the home (including set-top boxes), consumers will use it over time, rather than immediately. This creates a look-ahead opportunity, or innate capability, waiting to be tapped.

Currently, DLNA creates an island of networked media within the home - just begging to be taken to the next level. While DLNA has aspirations to connect to the unmanaged Internet, this is beyhond its current scope and presents a unique opportunity. Here's a set of recommendations for embracing DLNA, expanding its current vocabulary and extending its uses outside its currently restricted domain:

• Continue engaging with the standards group to ensure that their devices placed in consumer homes adhere to DLNA. The key is to push the envelope of DLNA capabilities that would increasingly leverage their penetration of premium services, such as HD content.

• Enable user interfaces to discover other DLNA equipment available on the consumer home network, such as digital surround receivers, and give consumers the option to route the sound of their TV programming accordingly.

• Extend DLNA by hosting ultra-reliable, virtual DLNA devices such as media servers that offer consumers such benefits as lifetime storage for media, continuously updated DLNA capability, and even restricted sharing or bridging between two or more subscriber homes.

• Implement DLNA on digital phone service or provide translation bridges between DLNA and other lower data rate communications such as ZigBee to further open up the home for increasing innovation.

Treasure chest

DLNA is an opportunity for service providers to assert themselves as the masters of media within consumer homes at a time when CE manufacturers are beginning to open up their "treasure chest" and expose all their goodies for someone to finally pull it all together into one cohesive system.

The key here is that the TV set - or home theater system - is still the center of entertainment and represents the highest quality viewing or listening experience within the home. In recent years, the PC has challenged these occasionally, but it just can't deliver the same entertainment quality.

DLNA creates the bridge for these personal and portable media to flow back into

7

the TV set and home entertainment system where they can be enjoyed to the fullest extent possible.

Portable media will still have its place, as will the PC, but trend-setting audiophiles and videophiles see the dust settling around more traditional uses for CE devices like the stereo and the TV set. DLNA only modifies these devices slightly by extending them and has the capability to be the fundamental cornerstone that will lead to simplifying the interoperability of devices and media applications within the home.

8

Why DLNA?

Today, consumers are accustomed to work with digital media on a large scale. Be it acquiring, viewing or managing the digital media on devices on personal computers, laptops, consumer electronics (CE), handheld devices like mobile phones etc in a networked environment. They wish to enjoy sharing the digital content easily and conveniently across different devices and locations in the home or office environment, regardless of the source.  Three main pools of electronic goods that prevail in today's world are  

The traditional consumer electronics goods The PC Internet World The Mobile World of multimedia mobile phones, personal digital

assistants, digital music players, laptop computers and similar devices with unparalleled connectivity.

   

   Consumers wish to inter-operate in these 3 zones and with new advancements in each or all of these areas, their expectations have grown. 

9

Yet their expectations are simple. 

Products must interoperate with each other without requiring the consumer to exercise complex setup and configuration for connection between devices.

Digital home products must interoperate with each other and with existing CE devices such as TVs and stereos.

Device discovery must be automatic. Digital Living Network Alliance (DLNA) is a cross-industry organization of leading operators of these 3 islands (zones) - consumer electronics, computing industry and mobile devices. They develop and share a vision of a wired and wireless network of interoperable consumer electronics, personal computers and mobile devices in the home and on the road, enabling a seamless environment for sharing and growing new digital media and content services.

10

Veer:

11

Technical view of a DLNA network

At a basic level, a DLNA enabled home network will look like below technically:

12

Networking and connectivity:

When the term was coined out primitively, “Networking” meant connecting devices over a zone though wires. The foundation for connectivity and networking was laid by the IPv4 family of protocols. IPv4 widely called IP got implemented and supported over a range of devices with more than two decades of deployment in commercial, official, Govt. and academic areas.

With the network addresses getting depleted, IPv6 protocol emerged, an improved version of IPv4.The IETF (Internet Engineering Task Force) is actively involved in migrating the devices from IPv4 to IPv6 network In longer term, IPv6 will become essential for interoperability of devices over a wired network and this is being thoughtfully handled in DLNA Network Device Interoperability Guidelines.

Advantages of using IP in digital home network:/* rephrase this */

IP allows applications running over different media to communicate transparently. For example, a PC or an advanced set top box may stream media content to a television in the master bedroom through an Ethernet cable to an 802.11 Access Point and then wirelessly to the television. With IP, the media server and the television are unaware that the media content travels over two separate physical media. For direct peer-to-peer communications of a mobile device transmitting to a stationary device, IP provides the unifying framework to make applications independent of the actual transport technology.

IP can connect every device in the home to the Internet. Since IP is the protocol of the Internet, any device in the digital home can be potentially connected to any other Internet-connected device in the world.

IP connectivity is inexpensive. Because it is ubiquitous, economies of scale and competition combine to make physical media implementations of IP available at lower cost than other technologies.

13

DLNA System Architecture

Pull-type architecture

The above diagram shows a DLNA Pull-type architecture. This is usually applied to desktop devices. It is natural for a user to browse a content directory locally on a desktop player, say a digital TV. A server may be placed anywhere else, say in another room.

The Pull-type Model has a Digital Media Player (DMP) which receives user commands through a

user interface (Pull-UI). The control server browses the Content Directory Service (CDS) for the

user’s query. Digital Media Server (DMS) detects the URL of the target content and

passes on to Transport client. The Transport client in DMP uses this URL to retrieve the target content

from the transport server in DMS. The play engine in DMP receives the content and renders it on a display. Note that there is no user interface in the DMS.

14

Push-type architecture

The Push-type architecture is suitable for handheld mobile devices. It provides direct control methods on content servers.

This model has a Digital Media Renderer (DMR) is adopted as the player.It has no user

interface The Play engine is controllable from outside. Push controller is added into the DMS which provides push controlling

functions (i.e. a user interface and a player control function).

15

To achieve interoperability, the medium over which the devices interact must be transparent. The building blocks needed to facilitate this interoperability are:

Networking and connectivity:

The devices are directly connected to each other over the link layer. WhenDevices residing on different link layer technologies need to communicate with each other, appropriate layer 2 bridging and layer 3 or the network layer/router routing must exist between these devices. The overall goal is to enable end-to-end connectivity between all devices exchanging information over the home network.

Device discovery:

The discovery of the device in the networked environment must be automatic.One device in the network must be able to discover the presence of other devices and services on the network and identify their own functions and associated capabilities. All these features must be backed by an ease –of-use.

Common media formats and streaming protocols:

For the devices to communicate they require a common media format and they need to agree on a common streaming protocol for streaming sessions for audio and video.

Interoperability among devices of different vendors:

The customers may possess a Samsung TV, a Sony music player, Apple’s iPod and so on. For such devices to communicate with each other there must be interoperable media management across all devices. It must include the ability to organize, browse, search, and select media items to be processed, in addition to the ability to control the operation of media streaming sessions.

Quality of Service (QoS):

For transferring high-definition media streams in the digital home, manufacturers must agree on how to address QoS in the digital home.

Compatible authentication and authorization mechanisms for users and devices:

Authentication is for the device to identify itself in the pool.Authorization is for the network/central system to decide what rights the authenticated device has.

16

It is vital to settle on compatible authentication and authorization mechanisms that enable devices to request and/or grant access to particular devices and services in the home.

17

Device discovery:

18

Sudee:

19

Common media formats :

20

Quality of Service (QoS):

21

Authentication and Authorization:

22

Digital Rights Management:

23

Use Cases

 

24

Conclusion:

-----------------------------------------------------------------------JUS IN CASE IF U FEEL THIS SHOULD BE ADDED-----------------------------------------------------------------------

1: Example when connecting to a personal computer using a wired connection

25

2: Example when connecting to a personal computer using a wireless connection

26

What Can We Say About DLNA?

Home multimedia devices will start sporting the Digital Living Network Alliance (DLNA) logo this year, and the number of products adopting this standard will likely increase. Most vendors of multimedia hardware are members of DLNA and have access to its standards. The cost of joining is minimal, and it's a requirement for getting devices DLNA-logo certified.

Meanwhile, we can provide a little insight into the structure and operation of DLNA devices since they're based upon the open Universal Plug-n-Play (UPnP) standard. The DLNA standard specifies the required UPnP subset that every DLNA device must support.

It's possible to support more of the UPnP standard, provide more mediaformatted files, and still comply with the standard. UPnP also defines a range of devices that DLNA does not cover, such as lighting controls. Still, all the UPnP devices should be able to coexist if not interact with each other at some level.

A typical mechanism implemented on DLNA media servers, real-time transcoding, lets devices maintain data in a single format but deliver it to another DLNA device in another format. Of course, this means the server requires enough horsepower to handle the transcoding.

DLNA devices use the standard UPnP discovery and control protocols to identify new devices. Application software is still required to handle the presentation and control interaction, but these applications will utilize the UPnP application programming interface (API) standard.

The DLNA standard is likely to expand over time to incorporate more devices and extend the functionality available between devices. Digital rights management (DRM) support is part of the standard, but you will need to become a DLNA member to find out the requirements.

Most UPnP stack developers also have a DLNA variant. This will make the job of creating a DLNA-compatible device easier.

http://electronicde

27