FACULTY OF INFORMATION TECHNOLOGY & MULTIMEDIA COMMUNICATION
SEMESTER JANUARY 2011
CBMM 4103
MULTIMEDIA SYSTEM
MATRICULATION NO. : 780222055921002
IDENTITY CARD NO. : 780222-05-5921
TELEPHONE NO. : 0192553069
E-MAIL : mohd.izuddin@mmu.edu.my
LEARNING CENTRE : UKM, Bangi
Table Of Content Page
1.0 Two advantages of Packet Switched Streaming 3
2.0 One technology using PSS. 5
3.0 How reliable is the Circuit Switch compared to Packet Switch 6
4.0 Three differences between Multimedia Broadcast and Multicast Service. 7
5.0 IPTV 8
6.0 Five challenges of Multimedia Messaging Services 9
7.0 Five types of Protocol Data Units in MMS level. 11
8.0 Attachment 13
1.0 Two advantages of Packet Switched Streaming
There are two examples of Packet Switched Technology such as LAN and internet. The main advantage Packet Switched Streaming has over all previous generation mobile communication systems is an increase in bit rate. Higher bit rate capabilities have delivered by service providers to involve into developing many bandwidth intensive applications that would not have been conceived of otherwise. There is tremendous excitement about the development of Packet Switched Streaming Technology. Two major forces are driving the development of these 3G systems. The first is the demand for higher data rate services, such as high-speed wireless Internet access. The second requirement are the more efficient use of the available radio frequency (RF) spectrum. This second requirement is a consequence of the projected growth in worldwide usage of wireless services. High-speed access, supporting broadband services such as fast Internet access or multimedia-type applications. One other advantages of packet switched streaming is we don’t need to wait until the content download completely to see the streaming because it can be seen will the buffering is in progress. The second advantages of packet-switching is that it permits statistical multiplexing on the communications lines. The packets from many different sources can share a line, allowing for very efficient use of the fixed capacity. With current technology, packets are generally accepted onto the network on a first-come, first-served basis. If the network becomes overloaded, packets are delayed or discarded .
Packet-Switched Streaming Services is a standard defined by the Third Generation Partnership Project (3GPP). The PSS specification covers the protocols and codecs necessary for the delivery of streaming content to multimedia terminals in Third Generation (3G) wireless networks. Packet-Switched Streaming Services also has many other advantages, with PSS we can run many application such as :
1. Viewing on-demand audiovisual clips from anywhere using a multimedia-equipped wireless phone.
2. Viewing subscription content (e.g. personalized news, business info, sports highlights, etc).
3. Watching content from a live camera (e.g. webcam or security camera).
4. Streaming content received via 3GPP's Multimedia Messaging Service (MMS).
The main focus of PSS is the communication between server and terminal. The PSS specification tells operators and equipment manufacturers how the server and terminal must behave in order to enable the streaming service
The PSS specification defines a multimedia streaming service within 3G wireless networks, and so enables the application scenarios mentioned above, as well as others. An important point is that PSS standardizes the communication used in the service. This makes it possible for vendors to design equipment that will interoperate (i.e. communicate properly with equipment from other vendors). For example, one company could provide a streaming server, and another company could provide the client solution.
While the PSS specification is defined to enable interoperable implementations, the specification itself cannot guarantee interoperability. Implementations from different companies must be tested together to ensure that the implementations are correct, and that companies have a consistent interpretation of the specification. Testing is also needed to identify and correct parts of the specification which are unclear or inconsistent.
2.0 One technology using PSS.
One technology using Packet Switched Technology is video streaming, video streaming is a technique for transferring data such that it can be processed as a steady and continuous stream. Besides that, streaming audio defines a method of delivering an audio signal to computer over the Internet, and differs from the normal method of receiving internet audio in one important way: instead of having to download a .wav file completely before being able to listen to it, you hear the sound as it arrives at your computer, and therefore do not have to wait for a complete download. However, video streaming is different compared to streaming audio. This is because it is a method of making audio, video and other multimedia available in real-time over the Internet with no download wait and no file to take up space on hard disk. Streaming technologies for transmitting real time continuous audio poses manychallenges in various areas including media compression, application QOS control, continuous media distribution services, streaming servers, media synchronization mechanisms.
Video Streaming works like this, the data arrives it is buffered for a few seconds and then playback begins. As the audio is playing, more data is constantly arriving, and as long as you are receiving a constant stream of data, you should hear constant audio. Think of a bucket (the buffer) with a hole in the bottom, being topped up with water (the data). As long as there is water in the bucket, it will continue to pour out of the hole, and will do this as long as there is water in the bucket. Similarly, as long as there is data in the buffer, you will continue to hear sound. Unfortunately the buffer can empty due to congestion on the Internet which may stop you from receiving data. To stream files from one machine to another, we use a streaming server. A streaming media server is similar to a web server in that it takes requests from users and sends files in return. We use metafiles in order for the streaming server to interact with web servers. When a file is placed on a streaming server, another file must be created that will point to the media file on the streaming server from a web server. The web server provides the user with a link on which to click to then locate the stream. This is known as a metafile and it contains code similar to HTML which lists the name of the server, the directory path to locate the file, and the protocol (or communication mechanism) the server will use to stream the file back to you.
3.0 How reliable is the Circuit Switch compared to Packet Switch
Figure 1: Circuit Switching
Circuit-switching is more reliable than packet-switching. When you have a circuit dedicated for a session, you are sure to get all information across. When you use a circuit which is open for other services, then there is a big possibility of congestion , and hence the delays or even packet loss. This explains the relatively lower quality of VoIP voice compared to PSTN. But you actually have other protocols giving a helping hand in making packet-switching techniques to make connections more reliable. Example of Circuit Switch are PSTN and ISDN. Other than that, in circuit switch data arrived in order. Example of packet-switching are LAN and internet.
Other than that, network resources reserved and dedicated from sender to receiver compared to packet switch where don’t have any dedicated connection, it has possible congestion and consequent packet dropping.In circuit switch we need to establish the connection first before send the data to destination. After that, the connection will be terminated. Circuit switch also provide traffic isolation and traffic engineering.In circuit switch also data arrived at constant rate and used when transmitting real time data, such as video and audio.
Other than that, Circuit switch is most efficient for longer transmission and low overhead requirement compared to packet-switched.
4.0 Three differences between Multimedia Broadcast and Multicast Service.
Broadcast service is a unidirectional point-to-multipoint service in which data is transmitted from single source to multiple UE's in the associated broadcast area, Multicast service is a unidirectional point-to-multipoint service in which data is transmitted from single source to Multicast group in associated Multicast area.
Broadcast services are push type services. The end user does not have to subscribe to be part of broadcast group, but in multicast, the end user has to be part of multicast group to receive the services.
In Broadcast there is no interaction possible but in multicast, interaction is possible, multicast users have a return channel for the interaction procedure. In Broadcast, they are free for example TV1, TV2 and TV3 but in Multicast, they could be free or paid. Multicasting may be used for streaming multimedia, video conferencing, shared white boards and more as the internet grows. Multicasting is still new to the internet and not widely supported by routers. New routing protocols are being developed to enable multicast traffic to be routed. Some of these routing protocols are:
• Hierarchical Distance Vector Multicast Routing Protocol (HDVMRP)
• Multicast Border Gateway
• Protocol Independent Multicast
Since IP is not a reliable network protocol, a new reliable multicast protocol that works at the transport layer and uses IP at the network layer has been developed. It is called Multicast Transport Protocol (MTP).
5.0 IPTV
Internet Protocol TV is becoming the new standard in offering TV over the existing Telco broadband network. Next generation networks will support data, voice and IPTV/Video on demand, so called triple play service. However, IPTV has stringent delay, jitter, bandwidth and QoS requirements, which bring great challenges to the last meter home networks. IPTV consists of four main components such as video headend, core network, access network and home network. All programming content is captured by video headend. This include linear TV programs and Video on Demand contents, Typically video ingests this content thru satellite or fiber network. It also responsible for encoding video streams into certain format. The content is broken into IP Packets that are sent thru IP multicast and IP unicast.
Internet Protocol television (IPTV) is a system through which Internet television services are delivered using the architecture and networking methods of the Internet Protocol Suite over a packet-switched network infrastructure, for the Internet and broadband Internet access networks, instead of being delivered through traditional radio frequency broadcast, satellite signal, and cable television (CATV) formats.
IPTV services may be classified into three main groups:
• live television, with or without interactivity related to the current TV show;
• time-shifted programming: catch-up TV (replays a TV show that was broadcast hours or days ago), start-over TV (replays the current TV show from its beginning);
• video on demand (VOD): browse a catalog of videos, not related to TV programming.
IPTV is distinguished from general Internet-based or web-based multimedia services by its on-going standardization process (e.g., European Telecommunications Standards Institute) and preferential deployment scenarios in subscriber-based telecommunications networks with high-speed access channels into end-user premises via set-top boxes or other customer-premises equipment.
6.0 Five challenges of Multimedia Messaging Services
1. Content adaptation:
Multimedia content created by one brand of MMS phone may not be entirely compatible with the capabilities of the recipient's MMS phone. In the MMS architecture, the recipient MMSC is responsible for providing for content adaptation , if this feature is enabled by the mobile network operator. When content adaptation is supported by a network operator, its MMS subscribers enjoy compatibility with a larger network of MMS users than would otherwise be available.
2. Distribution lists:
Current MMS specifications do not include distribution lists nor methods by which large numbers of recipients can be conveniently addressed, particularly by content providers, called Value-added service providers (VASPs) in 3GPP. Since most SMSC vendors have adopted FTP as an ad-hoc method by which large distribution lists are transferred to the SMSC prior to being used in a bulk-messaging SMS submission, it is expected that MMSC vendors will also adopt FTP.
3. Bulk messaging:
The flow of peer-to-peer MMS messaging involves several over-the-air transactions that become inefficient when MMS is used to send messages to large numbers of subscribers, as is typically the case for VASPs. For example, when one MMS message is submitted to a very large number of recipients, it is possible to receive a delivery report and read-reply report for each and every recipient. Future MMS specification work is likely to optimize and reduce the transactional overhead for the bulk-messaging case.
4. Handset Configuration:
Unlike SMS, MMS requires a number of handset parameters to be set. Poor handset configuration is often blamed as the first point of failure for many users. Service settings are sometimes preconfigured on the handset, but mobile operators are now looking at new device management technologies as a means of delivering the necessary settings for data services (MMS, WAP, etc.) via over-the-air programming.
5. WAP Push:
Few mobile network operators offer direct connectivity to their MMSCs for content providers. This has resulted in many content providers using WAP push as the only method available to deliver rich content to mobile handsets. WAP push enables rich content to be delivered to a handset by specifying the URL (via binary SMS) of a pre-compiled MMS, hosted on a content provider's web server. A consequence is that the receiver who pays WAP per kb or minute (as opposed to a flat monthly fee) pays for receiving the MMS, as opposed to only paying for sending one, and also paying a different rate.
7.0 Five types of Protocol Data Units in MMS level.
1. Send message to MMS Proxy -Relay (M -Send.req, M -Send.conf)
This chapter describes the header fields of the M-Send.req sent by the MMS Client to the MMS Proxy -Relay, and how these header fields may be modified by the sender's MMS Proxy -Relay. These header fields are used to generate the MMS notification to the recipient, and are delivered with the message body parts to the recipient MMS Client at retrieval.
2. Fetch message from MMS Proxy -Relay (WSP/HTTP GET.req, M -Retrieve.conf)
A MMS Client SHALL request the retrieval of an MM by sending a WSP/HTTP GET request to the MMS Proxy –Relay containing a URI that indicates the location of the MM to be retrieved. When successful, the response to the retrieve request will be M-Retrieve.conf PDU containing MMS header and the
3. Delivery Report about sent message (M-Delivery.ind)
A MMS Delivery Report MUST be sent from the MMS Proxy -Relay to the originator MMS Client or the forwarding MMS Client when a delivery report has been requested and the recipient MMS Client has not explicitly requested for denial of the report. As for example, the recipient can request for denial of the Delivery Report by using the X-Mms- Report-Allowed field of M-Acknowledge.ind or M-NotifyResp.ind PDU. There will be a separate delivery report from each recipient. There is no response PDU to the delivery report.
4. Acknowledgement of message delivery (M-Acknowledge.ind)
A M-Acknowledge.ind PDU confirms the delivery of the MM to the MMS Proxy -Relay.
5. Read Report about sent message (M-Read-Rec.ind, M-Read-Orig.ind)
Read reporting can be done either in the form of a new MM or be handled by specific PDUs. Backward compatibility between these methods is handled with the X-Mms-MMS-Version header field and a transformation mechanism in the originating Proxy -Relay. If the MMS Client is of higher version than 1.0 and if it supports read reporting it MUST also support the handling of Read Report PDUs.
ATTACHMENT
REFERENCES
WIKIPEDIA.(2011).MULTIMEDIA MESSAGING SERVICE.[ONLINE].AVAILABLE: HTTP://EN.WIKIPEDIA.ORG/WIKI/MULTIMEDIA_MESSAGING_SERVICE.[2011 MARCH 01]
IMTC.(2011).International Multimedia Telecommunication Cosortium.[Online].Available: http://www.imtc.org/activity_groups/ag_pss/faq.asp.[2011 March 5]
Answer.com.(2011). Advantages of circuit switching network over packet network?.[Online].Available: http://wiki.answers.com/Q/Advantages_of_circuit_switching_network_over_packet_network#ixzz1FD7MbHuL.[2011, Feb 2)
Charles, M.Kozierok.(2005).Circuit Switching And Packet Switching Networks.[Online].Available: http://www.tcpipguide.com/free/t_CircuitSwitchingandPacketSwitchingNetworks.htm.[2011, March 10]
Total Words=2500 Words
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