Simulation of Session Initiation Protocol There are many applications of the Internet that require the creation and management of a session, where a session is considered an exchange of data between an association of participants. Session Initiation Protocol (SIP) is an application-layer control protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, multimedia distribution and multimedia conferences. Course Name : Networking Level(UG/PG): UG Author : Phani Swathi Chitta Mentor : Aruna Adil *The contents in this ppt are licensed under Creative Commons Attribution-NonCommercial-ShareAlike 2.5 India license 1

Learning Objectives After interacting with this Learning Object, the learner will be able to: Explain how Session Initiation Protocol(SIP) works 2

1 2 3 4 5 Definitions of the components/Keywords: SIP (Session Initiation Protocol) is a signaling protocol used to create, manage and terminate sessions in an IP based network. It is an application-layer control (signaling) protocol for creating, modifying and terminating sessions with one or more participants. It is a text-based protocol, similar to HTTP and SMTP, for initiating interactive communication sessions between users. Such sessions include voice, video, chat, interactive games, and virtual reality.  It can also invite participants to already existing sessions, such as multicast conferences. Media can be added to (and removed from) an existing session. It is not a vertically integrated communications system. It is rather a component that can be used with other IETF ( Internet Engineering Task Force) protocols to build a complete multimedia architecture. 2 3 4 5 3 3

1 2 3 4 5 Definitions of the components/Keywords: Functions of SIP: SIP is limited to only the setup, modification and termination of sessions. It serves four major purposes SIP allows for the establishment of user location (i.e. translating from a user's name to their current network address). SIP provides for feature negotiation so that all of the participants in a session can agree on the features to be supported among them. SIP is a mechanism for call management - for example adding, dropping, or transferring participants. SIP allows for changing features of a session while it is in progress. 2 3 4 5

1 2 3 4 5 Definitions of the components/Keywords: Components of SIP: Entities interacting in a SIP scenario are called User Agents (UA) User Agents may operate in two fashions -  User Agent Client (UAC): A user agent client is a logical entity that creates a new request, and then uses the client transaction state machinery to send it. The role of UAC lasts only for the duration of that transaction. In other words, if a piece of software initiates a request, it acts as a UAC for the duration of that transaction. If it receives a request later, it assumes the role of a user agent server for the processing of that transaction. User Agent Server (UAS): A user agent server is a logical entity that generates a response to a SIP request. The response accepts, rejects, or redirects the request. This role lasts only for the duration of that transaction. In other words, if a piece of software responds to a request, it acts as a UAS for the duration of that transaction. If it generates a request later, it assumes the role of a user agent client for the processing of that transaction. Client: A client is any network element that sends SIP requests and receives SIP responses. Clients may or may not interact directly with a human user. User agent clients and proxies are clients. 2 3 4 5

1 2 3 4 5 Definitions of the components/Keywords: Server: A server is a network element that receives requests in order to service them and sends back responses to those requests. Examples of servers are proxies, user agent servers, redirect servers, and registrars. Proxy Server: An intermediary entity that acts as both a server and a client for the purpose of making requests on behalf of other clients. A proxy server primarily plays the role of routing, which means its job is to ensure that a request is sent to another entity "closer" to the targeted user. Proxies are also useful for enforcing policy (for example, making sure a user is allowed to make a call). A proxy interprets, and, if necessary, rewrites specific parts of a request message before forwarding it. Redirect Server: A redirect server is a user agent server that generates 3xx responses to requests it receives, directing the client to contact an alternate set of URIs. Registrar: A registrar is a server that accepts REGISTER requests and places the information it receives in those requests into the location service for the domain it handles. 2 3 4 5

1 Master Layout 2 3 4 5 Select the methods SIP Trapezoid Simulation Area Control Area Select the methods SIP Trapezoid Locating Users Proxy Mode Operation Redirect Mode Operation Parallel Forking Sequential Forking 2 3 Fig. A 4 Give START and RESET buttons Give a text area to display the status of the simulation For SIP Trapezoid refer slides 8 – 59 For Locating Users refer slides 60 – 89 For Proxy Mode Operation refer slides 90 – 123 For Redirect Mode Operation refer slides 124 – 155 For Parallel Forking refer slides 156 – 215 For Sequential Forking refer slides 216 – 240 5 7

3 Step 1: 1 2 4 5 SIP Trapezoid START RESET Instruction for the animator Text to be displayed in the working area (DT) When SIP Trapezoid is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area: This applet simulates Setting-up of SIP sessions with the help of SIP trapezoid. SIP consists of four entities sender, sender's proxy, receiver and receiver's proxy. First, sender sends INVITE to its proxy, which forwards it to receiver's proxy and then sends TRYING to sender. At the same time receiver's proxy forwards INVITE to Receiver and sends TRYING to sender's proxy. Now receiver responds with 180 RINGING which is carried to the sender through proxies. Receiver sends 200 OK which is forwarded to the sender through proxies. When sender receives 200 OK it responds with ACK which is sent directly to receiver. Session is established when receiver gets ACK. To terminate the session receiver sends BYE to the sender. Sender responds with 200 OK and session is terminated.

3 Step 2: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 25: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 26: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 27: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 28: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 29: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 30: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 31: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 32: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 33: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 34: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 35: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 36: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 37: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 38: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 39: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 40: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 41: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 42: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 43: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 44: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 45: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 46: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 47: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 48: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 49: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 50: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 51: 1 2 4 5 SIP Trapezoid Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 1: 1 2 4 5 Locating Users START RESET Instruction for the animator Text to be displayed in the working area (DT) When Locating users is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area: This applet simulates the function of Locating Users. It involves basic components such as Registrar, Location Server and Proxy Server. Registration: Mr.A@example.com is registered in the registrar. Also Contact information is stored. This means Mr.A can be found at Mr.A@pc17 Next INVITE is sent to proxy server with the help of the registered address. Proxy interacts with Location Server which in turn communicates with the Registrar through SQL, Corba, LDAP, etc. Location server retrieves the actual address from the Registrar and sends it to the proxy. Proxy generates new INVITE which is INVITE Mr.A@pc17.example.com

3 Step 2: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 25: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 26: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 27: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 28: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 29: 1 2 4 5 Locating Users Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 1: 1 2 4 5 Proxy Mode Operation START RESET Instruction for the animator Text to be displayed in the working area (DT) When proxy mode operation is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area:
This Applet simulates the protocol exchanges for the INVITE method in Proxy Mode. The proxy server accepts the INVITE request, contacts the location service with all or parts of the address and obtains a more precise location. The proxy server then issues a SIP INVITE request to the address(es) returned by the location service. The user agent server alerts the user and returns a success indication to the proxy server. The proxy server then returns the success result to the original caller. The receipt of this message is confirmed by the caller using an ACK request, which is forwarded to the callee. Note that an ACK can also be sent directly to the callee, bypassing the proxy. All requests and responses have the same Call-ID.

3 Step 2: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 25: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 26: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 27: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 28: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 29: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 30: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 31: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 32: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 33: 1 2 4 5 Proxy Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 1: 1 2 4 5 Redirect Mode Operation START RESET Instruction for the animator Text to be displayed in the working area (DT) When redirect mode operation is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area:

This Applet simulates the protocol exchanges for the INVITE method in Redirect Mode. The redirect server accepts the INVITE request, contacts the location service. Instead of contacting the newly found address itself, it returns the address to the caller, which is then acknowledged via an ACK request. The caller issues a new request, with the same call-ID but a higher CSeq, to the address returned by the first server. In the example, the call succeeds. The caller and callee complete the handshake with an ACK.

3 Step 2: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 25: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 26: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 27: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 28: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 29: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 30: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 31: 1 2 4 5 Redirect Mode Operation Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 1: 1 2 4 5 Parallel Forking START RESET Instruction for the animator Text to be displayed in the working area (DT) When parallel forking is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area: This Applet simulates the SIP Forking in Parallel Mode. Mr.A(User Agent Client) wants to communicate with Mr.B (User Agent Server). Mr.B can be present either at home or at workplace. Hence two different UASs are shown(Mr.B@home , Mr.B@work). UAC sends INIVITE to Proxy Server. Proxy Server forwards INVITE to both the UASs and sends TRYING to UAC. Both UASs ring, RINGING is sent to the UAC. Mr.A attains the call at the first UAS i.e. Mr.B@home. 200 OK is sent to the UAC. Proxy Server now invokes CANCEL method to Mr.B@work to cancel the INVITE method. Mr.B@work recieves the message responds with 200 OK, cancells the call and sends 487 Cancelled to the proxy. Proxy responds with an ACK. UAC sends ACK directly to Mr.B@home to establish the session. Session is established.

3 Step 2: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 25: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 26: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 27: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 28: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 29: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 30: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 31: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 32: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 33: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 34: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 35: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 36: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 37: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 38: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 39: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 40: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 41: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 42: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 43: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 44: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 45: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 46: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 47: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 48: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 49: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 50: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 51: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 52: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 53: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 54: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 55: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 56: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 57: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 58: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 59: 1 2 4 5 Parallel Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 1: 1 2 4 5 Sequential Forking START RESET Instruction for the animator Text to be displayed in the working area (DT) When sequential forking is selected, display the figures as shown above The buttons shown in the figure are to be displayed After START is pressed, disable the button The text in DT should appear in parallel to the figures Text given in next slide should be shown in the explanation area Press START button to run animation Press RESET button to reset 5

Text to be displayed in explanation area: This Applet simulates the SIP Forking in Sequential Mode. Proxy Server receives INVITE from sender. It sequentially forwards the INVITE to different locations. 'q’ values are used to govern order of sequential search. Location with the highest 'q' receives INVITE first. In this Example, INVITE is sent to Redirect Server first as its 'q' value is greatest. It responds with 302 Moved Temporarily. Proxy continues the search with next highest 'q‘ value. But it receives 486 Busy and hence neglects that location. Sequential Search continues and finally it receives 200 OK. Session is established.

3 Step 2: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given in previous slide throughout this part of animation 5

3 Step 3: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 4: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 5: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 6: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 7: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 8: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 9: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 10: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 11: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 12: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 13: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 14: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 15: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 16: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 17: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 18: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 19: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 20: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 21: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 22: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 23: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

3 Step 24: 1 2 4 5 Sequential Forking Instruction for the animator Text to be displayed in the working area (DT) Show the images and text as given in the above figure Update the status box according to the action being done Display the text given throughout this part of animation 5

Test your understanding Electrical Engineering Slide 1 Slide 3 Slide 242-245 Slide 246 Introduction Definitions Analogy Test your understanding (questionnaire)‏ Lets Sum up (summary)‏ Want to know more… (Further Reading)‏ Interactivity: There is no interactivity in this LO Try it yourself 241 Credits

Questionnaire 1 To which layer does Session Initiation Protocol (SIP) belong to? Answers: a) Session b) presentation c) Application d) Transport 2 3 4 5

Questionnaire 1 2. Can Session Initiation Protocol handle multicast / multimedia conferences? Answers: a) Yes b) No 2 3 4 5

Questionnaire 1 3. What is the server that acts as both a server and a client for the purpose of making requests? Answers: a) Redirect server b) Proxy server c) Location server d) Registrar 2 3 4 5

Questionnaire 1 4. What is the main function of SIP (Session Initiation Protocol) in an IP based network? Answers: a) create sessions b) manage sessions c) terminate sessions d)All the above 2 3 4 5

Links for further reading Reference websites: http://en.wikipedia.org/wiki/Session_Initiation_Protocol http://www.ietf.org/rfc/rfc3261.txt http://www.siptutorial.net/SIP/ http://www.ciscopress.com/articles/article.asp?p=664148 http://www.cisco.com/univercd/cc/td/doc/product/voice/sipsols/biggulp/bgsipov.htm http://www.slideshare.net/Sandra4211/intro-to-sip-ppt Books: 246