• 6. Glendon Holst (gholst@cs.sfu.ca)

    IEEE 1394b and Isochronous Traffic: An implementation and simulation in NS-2 comparing effective bandwidth usage. :

    Overview:

    IEEE 1394b is a proposed serial-bus interface and protocol that performs much like a packet switched network. The existing IEEE 1394a-2000 is a 400 Mbps technology, with IEEE 1394b extending that all the way up to 3.2 Gbps. More interestingly for us, IEEE 1394b also extends the link level protocol to support packet transmission or bus-arbitration immediately after an ACK, instead of waiting for the DELAY_TIMEOUT.

    Presently this technology shows up in computers, video cameras, stereo systems, high-speed peripherals, and more. It supports peer-to-peer communications (unlike USB which requires a single controlling host), and auto-detects the spanning tree for its network layout.

    Both IEEE 1394 technologies support two delivery modes:

    1) guaranteed delivery (asynchronous).
    2) guaranteed delay (isochronous).

    Isochronous transfer provides a fixed bandwidth channel over fixed time intervals. This mode is ideally suited to time-based multi-media applications such as video and audio.

    The goal for my project has two parts:

    1) Understand IEEE 1394b sufficiently to implement its PHY (equivalent to Ethernet's MAC) and Link layer protocols in NS-2. 2) Explore the bandwidth utilization of several IEEE 1394b networks of various sizes and loads, comparing the asynchronous and isochronous transfer modes.

    While such a comparison is interesting, it is not as applicable as I previously hoped. Since the isochronous transfer will not re-transmit lost packets, it is not suitable for all tasks (such as file transfers); further, IEEE 1394 uses bus arbitration (command packets) to determine who can transmit data next (unlike Ethernet, where simultaneous attempts at transmission will consume bandwidth). Since application needs are the primary constraint in choosing the transfer mode, it doesn't seem that isochronous transfer is a universal solution to improving efficient allocation of bandwidth. However, determining the overhead imposed by both transfer modes under a variety of network loads, is still interesting. It may even be possible to get a reliable isochronous transfer with a higher level protocol (e.g., using two isochronous channels -- one very low bandwidth one used for the ACKs).

    I already have NS2 installed, compiling and working in preparation for adding the IEEE 1394 related classes.

    References:

    Documentation is as follows:

    I will send the following PDF files to you other emails (they are to big to fit together):

  • P1394b Draft Standard for a High Performance Serial Bus: p1394b1-33.pdf What's New About 1394b: ppt1.pdf Isochronous Resource Management: br062r00.pdf New Technology for 1394 (overview): 1394ABoverview.pdf IEEE 1394-1995 High Performance Serial Bus (overview): 1394overview.pdf NS-2 Documentation (for implementation purposes): ns_doc.pdf
  • I will provide a printed version of the following references later:
  • Reservation arbitrated access - a bandwidth on demand protocol for multiplexing variable bit rate isochronous traffic over dual bus metropolitan area networks Chan H.C.B.; Leung V.C.M. Computer Networks and ISDN Systems, 15 December 1997, vol. 29, no. 16, pp. 1969-1990(22) Elsevier Science
  • Isochronous bandwidth utilization improvement in distributed queue dual bus-based personal communication networks Yang Y.; Lai T.-H.; Liu M.-T. Computer Communications, 15 October 1998, vol. 21, no. 16, pp. 1420-1433(14) Elsevier Science
  • Some additional sources of Information are as follows (tested 14/02/2002):
  • The 1394 trade association: http://www.1394ta.org/
  • 1394 specifications from 1394 trade association: http://www.1394ta.org/Technology/Specifications/index.htm http://www.1394ta.org/Technology/Specifications/specifications.htm
  • The meeting notes of the IEEE committee for 1394a: http://grouper.ieee.org/groups/1394/1/Documents/
  • The meeting notes of the IEEE committee for 1394b: http://www.zayante.com/p1394b/
  • Some overviews of 1394: http://www.iol.unh.edu/training/1394.html
  • NS Tutorials (including extending): http://nile.wpi.edu/NS/ http://www.isi.edu/nsnam/ns/tutorial/index.html