This document provides an overview of multimedia services over IP networks and discusses two key protocols used: SIP and H.323. It describes the basics of SIP including session descriptions using SDP, message format, and session initiation. It also discusses SIP applications like IMS including requirements, protocols used, and architecture. For H.323, it outlines the network architecture including terminals, MCUs, gateways, and gatekeepers. It then describes the H.323 signaling protocols including RAS, H.225 call signaling, and H.245 call control.
Chapter 4 - Introduction of International StandardsPratik Pradhan
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
Chapter 4 - Introduction of International StandardsPratik Pradhan
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
Developed by ITU-T, ISDN is a set of protocols that combines digital telephony and data transport services to digitise the telephone network to permit the transmission of audio, video and text over existing telephone line. ISDN is an effort to standardise subscriber services, provide user or network interface and facilitate the inter-networking capabilities of existing voice and data networks. The goal of ISDN is to form a wide area network that provides universal end-to-end connectivity over digital media by integrating separate transmission services into one without adding new links or subscriber links.
This study guide is intended to provide those pursuing the CCNA certification with a framework of what concepts need to be studied. This is not a comprehensive document containing all the secrets of the CCNA, nor is it a “braindump” of questions and answers.
I sincerely hope that this document provides some assistance and clarity in your studies.
H.323 is a recommendation from the ITU Telecommunication Standardization Sector (ITU-T) that defines the protocols to provide audio-visual communication sessions on any packet network.
The H.323 standard addresses call signaling and control, multimedia transport and control, and bandwidth control for point-to-point and multi-point conferences.
It is widely implemented by voice and videoconferencing equipment manufacturers, is used within various Internet real-time applications such as GnuGK and NetMeeting
It is widely deployed worldwide by service providers and enterprises for both voice and video services over IP networks.
It is a part of the ITU-T H.32x series of protocols, which also address multimedia communications over ISDN, the PSTN or SS7, and 3G
H.323 call signaling is based on the ITU-T Recommendation Q.931 protocol and is suited for transmitting calls across networks using a mixture of IP, PSTN, ISDN, and QSIG over ISDN.
This is the subject slides for the module MMS2401 - Multimedia System and Communication taught in Shepherd College of Media Technology, Affiliated with Purbanchal University.
Developed by ITU-T, ISDN is a set of protocols that combines digital telephony and data transport services to digitise the telephone network to permit the transmission of audio, video and text over existing telephone line. ISDN is an effort to standardise subscriber services, provide user or network interface and facilitate the inter-networking capabilities of existing voice and data networks. The goal of ISDN is to form a wide area network that provides universal end-to-end connectivity over digital media by integrating separate transmission services into one without adding new links or subscriber links.
This study guide is intended to provide those pursuing the CCNA certification with a framework of what concepts need to be studied. This is not a comprehensive document containing all the secrets of the CCNA, nor is it a “braindump” of questions and answers.
I sincerely hope that this document provides some assistance and clarity in your studies.
H.323 is a recommendation from the ITU Telecommunication Standardization Sector (ITU-T) that defines the protocols to provide audio-visual communication sessions on any packet network.
The H.323 standard addresses call signaling and control, multimedia transport and control, and bandwidth control for point-to-point and multi-point conferences.
It is widely implemented by voice and videoconferencing equipment manufacturers, is used within various Internet real-time applications such as GnuGK and NetMeeting
It is widely deployed worldwide by service providers and enterprises for both voice and video services over IP networks.
It is a part of the ITU-T H.32x series of protocols, which also address multimedia communications over ISDN, the PSTN or SS7, and 3G
H.323 call signaling is based on the ITU-T Recommendation Q.931 protocol and is suited for transmitting calls across networks using a mixture of IP, PSTN, ISDN, and QSIG over ISDN.
Hubble Telescope is used to observe in the near-infrared through the visible spectrum to the ultra-violet.
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Its advantage to avoid atmospheric turbulence.It has an extremely large field of view which is necessary to obtain high resolution images of large areas of the sky.
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Design of management Application allow to control the functionality of each device.
if some devices experience havoc, then we have to keep log of the wrecks of incidents.
With the use of SNMP-MIB we can keep log of the events occurred in the system, which would help in identifying the exact cause of the problems, and would help the administrator in recovery of system.
Example: consider an air conditioner , which can be controlled by service discovery like UPnP, but to monitor its performance, whether its cooling performance is appropriate or not, A management protocol like SNMP could be beneficial.
SNMP allows the standardization of the system and homogeneous interface to the administrator for the management of SNMP and UPnP based devices.
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possible solution of above mentioned problems by introducing
the process plane in the information content of Product model.
Process plane defines different kind of process involved during
the analysis, contexual, optimisation, decision and representation level of an engineering object. In this context, three kind of process are proposed namely Analysis process, Effect process and Optimisation process. Following this, Mathematical representation of every process and their relationship are accomplished. Finally, (requirements, functional, logical, and physical)RFLP structure is considered as an engineering object to explain the above mentioned concepts in the information content. This plane can provide all the necessary and important information related with an engineering object such that engineers can calculate
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basic technical standards for Internet protocols are set and maintained standardize all the protocol layers in between, from IP itself up to general applications like email and HTTP.
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kind of behavior of a product in the physical environment. In
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behavior modeling is accomplished in Function and Logical level.
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product system by proposing the Requirement, Function and
Logical Block corresponds to RFLP structure and then monitor
and improve the behavior of a product by using soft computing.
In this context, Mamdani FIS (Fuzzy Inference System) and
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behavior. Soft Computing, not only provide the solution of system
behavior monitoring but also improve the performance of a
system in terms of behavior such that product system are able
to work efficiently
This presentation describes role of orthogonal division mutiplexing in optical networks and electrical networks. It starts with introduction ofdm tecnique then move to role of OFDM in Electrical domain then optical domain
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## Understanding Internet Security
Internet security encompasses the measures and protocols used to protect information, devices, and networks from unauthorized access, attacks, and damage. It involves a wide range of practices designed to safeguard data confidentiality, integrity, and availability. Effective internet security is crucial for individuals, businesses, and governments alike, as cyber threats continue to evolve in complexity and scale.
### Key Components of Internet Security
1. **Confidentiality**: Ensuring that information is accessible only to those authorized to access it.
2. **Integrity**: Protecting information from being altered or tampered with by unauthorized parties.
3. **Availability**: Ensuring that authorized users have reliable access to information and resources when needed.
## Common Internet Security Threats
Cyber threats are numerous and constantly evolving. Understanding these threats is the first step in protecting against them. Some of the most common internet security threats include:
### Malware
Malware, or malicious software, is designed to harm, exploit, or otherwise compromise a device, network, or service. Common types of malware include:
- **Viruses**: Programs that attach themselves to legitimate software and replicate, spreading to other programs and files.
- **Worms**: Standalone malware that replicates itself to spread to other computers.
- **Trojan Horses**: Malicious software disguised as legitimate software.
- **Ransomware**: Malware that encrypts a user's files and demands a ransom for the decryption key.
- **Spyware**: Software that secretly monitors and collects user information.
### Phishing
Phishing is a social engineering attack that aims to steal sensitive information such as usernames, passwords, and credit card details. Attackers often masquerade as trusted entities in email or other communication channels, tricking victims into providing their information.
### Man-in-the-Middle (MitM) Attacks
MitM attacks occur when an attacker intercepts and potentially alters communication between two parties without their knowledge. This can lead to the unauthorized acquisition of sensitive information.
### Denial-of-Service (DoS) and Distributed Denial-of-Service (DDoS) Attacks
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test test test test testtest test testtest test testtest test testtest test ...
MULTIMEDIA SERVICES OVER IP NETWORKS
1. Coursework for IP Networks and Protocols
MULTIMEDIA SERVICES OVER IP
NETWORKS
Submitted by:
YatishBathla
Bruno Iniguez
2. INDEX OF MULTIMEDIA SERVICES IN IP NETWORKS
Coursework for IP Networks and Protocols
• Introduction to multimedia services in IP
network
• Problem statement
• Types of solutions
• SIP Protocol Basics
- Introduction
- Session Descriptions and SDP
- Message Format
- Session initiation
• SIP Based Application: IMS
2A. Introduction of IMS
- IMS Requirements
- Protocols used in the IMS
- IMS Architecture
2B. Session Control in the IMS
- Prerequisites Operation
- Session Setup
• H.323
3A. Introduction
• Network Architecture
• Network Elements
– Terminals
– MCU’s
• Gateways
– Gatekeepers
– Border Elements and Peer
Elements
• Protocols/Codecs
• 3B. Network Signaling
i. RAS Signaling
ii. H.225.0 Call Signaling
iii. H.245 Call Control
– Capability Negotiation
– Master/Slave
Determination
– Logical Channel Signaling
– Fast Connect
3. INTRODUCTION
Coursework for IP Networks and Protocols
• Today with the rise of multimedia and network technologies,
multimedia has become an indispensable feature on the Internet.
• Animation, voice and video clips become more and more popular on
the Internet. Multimedia networking products like Internet telephony,
Internet TV, video conferencing have appeared on the market.
• In the future, people would enjoy other multimedia products in
distance learning, distributed simulation, distributed work groups and
other areas.
• The Internet has experienced tremendous expansion in the past
several years. Demands for IP based multimedia services are emerging.
At the same time, cellular networks are evolving from circuit-switched,
voice-centric networks to third generation (3G) wireless networks that
support high-speed IP-based data, voice, and multimedia services.
5. Coursework for IP Networks and Protocols
• H. 323
• SIP
TYPE OF SOLUTION
6. Introduction of SIP Protocol
Coursework for IP Networks and Protocols
• SIP is based on HTTP and,
so, is a textual request-
response protocol.
• main goal of SIP is to deliver
a session description to a
user at their current
location
• Based on Offer/Answer
Model
• User register its complete
URI in Registrar server
• SIP makes mapping
between Public URI and
current URI
7. Session Description Protocol
Coursework for IP Networks and Protocols
• The most common format
for describing multimedia
sessions is the Session
Description Protocol (SDP).
a textual format to describe
multimedia sessions
• SDP description consists of
two parts: session-level
information and media-level
information
8. SIP Message Body
Coursework for IP Networks and Protocols
• SIP messages can carry any
type of body using MIME
(Multipurpose Internet Mail
Extensions) encoding
• Sender Terminal or / Server sends
SIP request called Request Line
Request line consist method
name, the Request-URI, the
protocol version and Header.
• Receiving Terminal or/ Server
reply SIP response called Status
Line
The status line contains the
protocol version ,the status of the
transaction and Header
9. SIP Message Body
Coursework for IP Networks and Protocols
• Right after the start line, SIP
messages contain a set of
header fields
• Six mandatory header fields
that appear in every SIP
message. They are
To, From, Cseq, Call-ID, Max-
Forwards, and Via
10. Session Initiation SIP
Coursework for IP Networks and Protocols
• Alice registers her current location
sip:alice@pda.com
• with the registrar at domain.com.
Alice sends a REGISTER request
indicating that requests addressed
to the URI in the To header field
sip:Alice.Smith@domain.com
• At a later time, Bob invites Alice to
an audio session. Bob sends an
INVITE request using Alice’s public
URI
• If, in the middle of the session,
they wanted to make any changes
to the session (e.g., add video), all
they would need to do would be to
issue another INVITE request with
an updated session description
11. SIP APPLICATION: IMS
Coursework for IP Networks and Protocols
• Third Generation (3G) networks aim to merge two of the most
successful paradigms in communications: cellular networks
and the Internet
• IMS to provide ubiquitous cellular access to all the services
that the Internet provides. Picture yourself accessing your
favorite web pages, reading your email, watching a movie, or
taking part in a videoconference wherever you are by simply
pulling a 3G hand-held device out of your pocket.
• IP Multimedia Subsystem is a Session Initiation Protocol
(SIP)-based IP Multimedia infrastructure that provides a
complete architecture and framework for real-time and non-
real-time IP multimedia services on the top of Packet
Switched (PS) core while still preserving the Circuit Switched
(CS) telephony services
12. IMS REQUIREMENT
Coursework for IP Networks and Protocols
• Support for establishing IP Multimedia Sessions.
• Support for a mechanism to negotiate Quality of Service
(QOS).
• Support for inter-working with the Internet and circuit-
switched networks.
• Support for roaming.
• Support for strong control imposed by the operator with
respect to the services delivered to the end-user.
• Support for rapid service creation without requiring
standardization.
13. PROTOCOL USED IN IMS
Coursework for IP Networks and Protocols
• Session Initiation Protocol (SIP):. SIP was chosen as the session
control protocol for the IMS. Since SIP is based on HTTP, SIP service
developers can use all the service frameworks developed for HTTP,
such as CGI (Common Gateway Interface) and Java servlets.
• Authentication, Authorization, and Accounting (AAA) protocol:
Diameter Protocol was chosen to be the AAA (Authentication,
Authorization, and Accounting) protocol in the IMS.
• Common Open Policy Service (COPS): used to transfer policies
between PDPs (Policy Decision Points) and PEPs (Policy Enforcement
Points)
• H.248: Its packages are used by signaling nodes to control nodes in
the media plane (e.g., a media gateway controller controlling a media
gateway).
• Real-Time Protocol (RTP) and Real-Time Control Protocol
(RTCP): transport media data such as video and audio.
16. Session Initiation: Prerequisite Operation Of IMS
Coursework for IP Networks and Protocols
• IP CAN: fixed environments are DSL,
Dial-up Lines, enterprise LAN, etc. In
wireless environments we have
Packet Data Access networks such as
GPRS or WLAN
• P-CSCF Discovery:
P-CSCF discovery may take place in
different ways:
a) integrated into the procedure that
gives access to the IP-CAN;
b) as a stand-alone procedure
19. H.323
Coursework for IP Networks and Protocols
• H.323* is a multimedia conferencing protocol, which includes voice, video,
and data conferencing, for use over packet networks
• Standard recommended by ITU-T
• Collection of Standards.
• H.323 belongs to the H.32x class of standards for videoconferencing
applications.
* H.323 is “ITU-T Recommendation H.323: Packet-based multimedia communications systems”
What is H.323?
20. H.323 Architecture
Coursework for IP Networks and Protocols
RR
Router
Gatekeeper
MCU
RR
RR
PSTN
Enterprise
Wireless
ISND
Gateway
Terminals
IP Network
• Terminals
• Gateways
• Multipoint Control Units
• Gatekeepers
• Border Elements
Endpoints
21. H.323: Terminals
Coursework for IP Networks and Protocols
• H.323 client endpoints
• They could be:
• Telephones
• Voicemail Systems
• “Soft phones” (e.g., NetMeeting®)
• Multimedia PCs
• Any stand-alone device
• Expectation by H.323:
• Must support audio communication.
• Video, data support optional
22. H.323: Gateways
Coursework for IP Networks and Protocols
ptional Component of H.323 implementation.
sed as interface between different networks e.g. LAN & PSTN
unctions:
• Data format translation
• Audio/video codec translation
• Call setup, termination from both sides of the network
23. H.323: Multipoint Control Unit (MCU)
Coursework for IP Networks and Protocols
ultipoint conferences (two or more endpoints engaged in a conference)
CUs are also optional in a H.323 implementation
eeded only when multiparty conferences are desired
unctions:
• Provides capability of video-conferencing with more than one party.
• Acts as a coordinator of multiparty conferences
24. H.323: Gatekeepers
Coursework for IP Networks and Protocols
Brains” of a H.323 network
xpectation by H.323:
• Address translation
• Admissions Control
• Bandwidth Control
• Zone Management
• Routing Capabilities
he Gatekeeper is an optional component in the H.323 system which is primarily used
for admission control and address resolution
he gatekeeper may allow calls to be placed directly between endpoints or it may
route the call signaling through itself to perform functions such as follow-me/find-me
and forward on busy
25. H.323: Border Elements and Peer Elements
Coursework for IP Networks and Protocols
• Peer Elements, which are often co-located with a Gatekeeper, exchange
addressing information and participate in call authorization within and
between administrative domains
• Peer Elements may aggregate address information to reduce the volume of
routing information passed through the network
• Border Elements are a special type of Peer Element that exists between two
administrative domains
• Border Elements may assist in call authorization/authentication directly
between two administrative domains or via a clearinghouse
26. Typical H.323 Protocol Stack
Coursework for IP Networks and Protocols
H.323
IP
UDP
RTP
RTCP
TCP/UDP TCP UDPUDP TCP
Audio
Codecs
G.711
G.723.1
G.729
..
Video
Codecs
H.261
H.263
H.264
..V.150 T.120
TCP/UDP
T.38
H.225.0
Call
Signaling
H.245
H.225.0
RAS
Terminal Control and Management
Data
Applications
Media Control
Multimedia Applications, User Interface
27. H.225.0 Call Signaling
Coursework for IP Networks and Protocols
Terminal
Setup
Call Proceeding
Connect
Release Complete
Terminal
Alerting
H.245 Session Establishment
H.245 Session Release
Media Exchange
Allows an endpoint to initiate and terminate a call with another endpoint
29. Registration, Admission, and Status - RAS Signaling
Coursework for IP Networks and Protocols
• Defined in H.225.0
• Allows an endpoint to request authorization to place or accept a call
• Allows a Gatekeeper to control access to and from devices under its control
• Allows a Gatekeeper to communicate the address of other endpoints
• Allows two Gatekeepers to easily exchange addressing information
GatekeeperTerminal Gatekeeper
GRQ
GRJ
GCF
GK discovery
GRQ
GRQ
30. Registration, Admission, and Status - RAS Signaling
Coursework for IP Networks and Protocols
Endpoints use the RAS protocol in order to communicate with a gatekeeper. Likewise, gatekeepers use RAS
to communicate with peer gatekeepers. RAS is a fairly simple protocol composed of just a few messages
• Gatekeeper request, reject, and confirm messages (GRx)
• Registration request, reject, and confirm messages (RRx)
• Unregister request, reject, and confirm messages (URx)
• Admission request, reject, and confirm messages (ARx)
• Bandwidth request, reject, and confirm message (BRx)
• Disengage request, reject, and confirm (DRx)
• Location request, reject, and confirm messages (LRx)
• Resource availability indication and confirm (RAx)
• Admission confirm sequence (ACS)
31. Registration, Admission, and Status - RAS Signaling
Coursework for IP Networks and Protocols
GatekeeperTerminal
RRQ
RCF
URQ
UCF
// //
32. Registration, Admission, and Status - RAS Signaling
Coursework for IP Networks and Protocols
ARQ
ACF
Setup
ACF
// // //
ARQ
DRQ
DCFDCF
DRQ
TerminalTerminal Gatekeeper
34. Coursework for IP Networks and Protocols
H.245 Call Control
• Provide more extensive control over the conference.
• H.245 provides capabilities such as capability
negotiation, master/slave determination, opening and closing of "logical channels"
(i.e., audio and video flows), flow control, and conference control.
Capability Negotiation
• Enables devices to communicate without having prior knowledge of the capabilities
of the remote entity.
Master/Slave Determination
• Once capabilities are exchanged, the endpoints negotiate master and slave roles.
• The master in a point to point conference really only has the power to indicate when
channels are in conflict (e.g., when one the other terminal tries to open a channel
that is not compatible)
• The slave device must yield to the requests of the master device and reconfigure
channels appropriately
35. Coursework for IP Networks and Protocols
H.245 Call Control
Logical Channel Signaling
•Once capabilities are exchanged and master/slave determination steps have completed,
devices may then open "logical channels" or media flows. This is done by simply sending
an Open Logical Channel (OLC) message and receiving an acknowledgement message.
Upon receipt of the acknowledgement message, an endpoint may then transmit audio or
video to the remote endpoint.
Fast Connect
•Fast Connect (also improperly referred to as “fast start”, after the name of the
associated field) is a means of establishing an H.323 call with as few as two
messages.With the use of Fast Connect, there is no need to open an H.245 channel, as
long as all needed media can be negotiated via Fast Connect
37. Coursework for IP Networks and Protocols
Use Cases
H.323 and Voice over IP services
ITU-T Recommendation H.323 is one of the standards used in VoIP.
H.323 and Videoconference services
Supports advanced videoconferencing features, including:
•Cascading MCUs
•MCU control over audio and video mixing
•Far-end camera control
H.323 recommendation is a “framework” document that describes how the various pieces fit together
H.225.0 defines the call signaling between endpoints and the Gatekeeper
RTP/RTCP (RFC 3550) is used to transmit media such as audio and video over IP networks
H.225.0 define the procedures and protocol for communication within and between Peer Elements
H.245 is the protocol used to control establishment and closure of media channels within the context of a call and to perform conference control
H.450.x is a series of supplementary service protocols
H.460.x is a series of version-independent extensions to the base H.323 protocol
T.120 specifies how to do data conferencing
T.38 defines how to relay fax signals
V.150.1 defines how to relay modem signals
H.235 defines security within H.323 systems
X.680 defines the ASN.1 syntax used by the Recommendations
X.691 defines the Packed Encoding Rules (PER) used to encode messages for transmission on the network
Audio:
G.711 (popular codec for telephone n/ws)
G.723.1 – more efficient
Video
H.261 codec (for channels with bandwidths p*64 kb/s)
H.263 codec (for low bit rate transmission without loss of quality )