Secure Multimedia Multicast: Interface and Multimedia Transmission GROUP 2: Melissa Barker Norman Lo Michael Mullinix server router client router client

What is Multicast? The most basic transmission method would be to send a single copy of data from the source (server) to each individual destination (client), which is known as unicast. This results in sending the same message multiple times to each of the individual destinations. To reduce congestion, multicast sends a single copy of data to each router its connected to and lets the routers decide whether it should make another copy of the information to send to the destination.

Multicast vs. Unicast Single virtual connection with a group address Uses only a little more bandwidth for a thousand clients than it does for a single client Access control difficult to implement because secret key is shared by all group members Point-to-Point Connection Consumes a lot of resources as number of clients increase (Congestion problems) Access control easy to implement because secret key can be established privately Server Client Group Address

What are the advantages of Multicast? (1) Decreased Network Utilization—Reduces the number of messages required by eliminating redundant packets and decreasing the number of point-to-point connections that must be established. Dynamic Participation—Multicasting provides flexibility in joining and leaving a group. This membership flexibility supports the transient behavior of peers.

What are the advantages of Multicast? (2) Multimedia support—Multimedia transmission continues to increase in popularity while at the same time it consumes a significant amount of bandwidth. This is one area where network optimization is of paramount importance. Multimedia data such as images, video, and audio generally require a large amount of memory and would require more time to transmit. Therefore it is highly profitable to reduce the number of redundant messages being sent in order to improve the efficiency of the system.

What is Secure Multicast? Many multicast applications require access control mechanisms to establish security in the system. Access control can be achieved by encryption. Since users may join and leave at any time, it is necessary to update the encryption keys. By establishing a key management structure, dynamic membership can be handled.

Key Management If a user leaves or stops paying for service, the encryption key must change so they can no longer decrypt data. Also, if a new user joins, the encryption key must change so they will not be able to decrypt any data collected before they started paying for the service.

Non-Tree Based Structure Tree based Structure If Client Joins: # of Messages = 2 If Client Leaves: # of Messages = N If Client Joins: # of Messages = L+1 If Client Leaves: # of Messages = D*L = 2*log 2 N (if tree binary) Session Key Key Encrypt Key Client Keys N = Number of Clients L = Level of Tree D = Degree of Tree K1K1 K0K0 Session Key Key Encrypt Key Client Keys

Goals Transmit and Display Multimedia Images Video Visualize the Key Management Process

Our Approach… 1. Meet with Professor and understand the Secure Multicast research and system provided. 2. Study the code to understand the system. 3. Build code in C to transfer and display a JPEG file. 4. Build code to transfer and display a sequence of JPEG files. 5. Build code to transmit the GOPs in a MPEG. 6. Build code to receive and play the MPEG data. 7. Build a graphical interface to visualize the key management process. 8. Create a User’s Manual.

Server Side (1) Request file type and file names Load Files Wait for client to join Check for client on Member List NOYES REJECTGenerate New Session Keys Key Visualization Given Created

Server Side (2) Update other Encryption Keys Send out Updated Keys Client Leaves Process multimedia data/Add Header TIMER Transmit Multimedia Data Key Visualization Generate New Session Keys

Client Side Register Request server to join Receive Session Key and Key Encryption Receive Data Decrypt the keys Process and Display Data to User

Visual Interface Use SVG to display tree structure for key management SVG – Scalable Vector Graphics developed by Adobe Developed based on XML and follow W3C Document Object Model (DOM) level 2 standard Deliver high quality image in efficient ways

Future Work Decode and Display Video Data Transmit and Receive Audio Data Complete Key Management Work Use Encryption for Multimedia

Secure Multimedia Multicast: Interface and Multimedia Transmission JPEG sequence MPEG DEMO

Works Cited ENEE408G Course Notes, Prof. Min Wu, Available online at Fall 2002 Final Presentation, MERIT Research Group, 2002 P2P Dynamic Networks, K. Ho, K. Patel, "MERIT 2002 README.txt," August 15, J. L. Mitchell, W.B Pennebaker, C.E. Fogg, and D. J. LeGall, "MPEG Video Compression Standard," International Thomson Publishers, J. Song, R. Poovendran, W. Trappe, and K.J. R. Liu, "A Dynamic Key Distribution Scheme using Data Embedding for Secure Multimedia Multicast." P. Pessi, "Secure Multicast," W. Trappe, J. Song, R. Poovendran, and K.J. R. Liu, "Key Management and Distribution for Secure Multimedia Multicast." T. Hardjono, G. Tsudik, "IP Multicast Security: Issues and Directions," W. Trappe, Y. Wang, K.J. R. Liu, "Establishment of Conference Keys in Heterogeneous Networks," H.M. Deitel, P.J. Deitel, "C++, How To Program," 2001.

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