CalTrans Testbed Center for Interoperability (TCFI)
This is my third internship report describing the tasks I have executed for the last Quarter. Three major tasks were executed as follows:
∑ Arranging Local Area Network for our new office, and connect our segment to UCSB backbone.
∑ Trained on using UML to generate an object oriented code using Java and C++.
∑ Test MPEG 4 standard using different wireless communication protocols mainly CDPD and 802.11b.
New Local Area Network:
One of my ongoing tasks is network administrator for our office as well as support for e-mail and web services. Our office has been recently located to an off campus location. My main duty was to supervise the installation of the local area network cabling and the distribution points for the Ether net ports in the office. The connection between our segment and UCSB backbone was carried out by GTE using OC12 fiber link.
With reference to my second internship report the e-mail server was upgraded from Linux 5.2 to 7.0 due to security issues arouse by UCSB network security office. During this quarter I did monitor the in- coming traffic on the open ports in a daily bases to ensure that the e-mail server was not hacked into. Furthermore, all the RPM packages were upgraded as they became available from Redhat Linux. Lastly, under my direct supervision Ying Yan (student Assistance) preformed the regular upgrades and the maintenance required for our web server† - Testbed center for intraoprobibility (TCFI).
Unified Modeling language (UML) training:
Under task order 301 and task order 303 an extensive knowledge is needed to develop an Object Oriented (OO) programs. With reference to my second internship report a complete flow charts for 2070 controller were generated from C code currently running the traffic controller. UML training was needed to continue the development of an OO program for the 2070 traffic controller signal. Accordingly, I attended a full training course on how to Implement a UML diagrams. Due to the fact that we did move from our office I was not able to produce a tangible results. However, the work on UML diagrams will be implemented over the next few weeks.
MPEG 4 Standard:
Under Task order 301 Testbed center for intraoprobibility is responsible for the examination of the different possibilities for Signal Processing, Imaging and Image Analysis (MPEG4, packet video, etc.) to support next generation surveillance, multimedia data exchange.
This responsibility came due to the fact that Caltrans urban Districts provide traffic surveillance and incident verification information to their Transportation Management Centers (TMC). TMC to TMC video communications is one of the most bandwidth demanding applications within Caltrans. TCFI is currently investigating many aspects of this application including the CORBA A/V streaming standards and MPEG-H.32X interoperability.
Since Mpeg-4 was designed for coding of progressive and interlaced video at transmission speeds down to 64 kb/s. It was designed to be able to represent units of aural, visual or audiovisual content, called "media objects", as separate entities that can be independently manipulated without affecting the rest of the scene. These media objects can be of natural or synthetic origin, in other words, recorded with a camera or microphone, or generated with a computer. They can be grouped together to create new media objects or entire scenes. In addition, MPEG 4 provides coding to multiplex and re-synchronize the data associated with various media objects so they can be transported over respective network channels that provide a QOS (Quality of Service) appropriate to the requirements (data transmission rates, bit error rates, etc.) of the specific media objects.† Finally, there is coding that allows interaction with the audiovisual scene generated at the receiverís end. This was the third MPEG standard to be developed. Version 1 was approved in October of 1998, and version 2 had been scheduled for approval as an international standard in December of 1999, but is still pending.
Accordingly, it was the choice to start investigating the possibility of using MPEG 4 as a standard to be used to stream A/V over a slow wireless links such as CDPD or 802.11b (Outdoor). Packet Video Inc. did provide a complete software package, which has the capability of encode, decode and stream the images over the Internet with a different transmission rate (9600 to custom settings). Figure (1) shows the over all system and the wireless communication protocol used to examine streaming A/V over the Internet.
PV Author server software:
PV Author server is responsible for the communication between the web server and the encoder software (PV author), which is installed on the digital video source. The video source usually is a computer system connected to a digital video camera. PV Arthur was developed to run Under Linux 6.2 OS.
Accordingly, to be able to broadcast the A/V over the Internet, the first step was to install the Linux 6.2 and configure apache server. I did not encounter any problems at this stage of installation. The second step was to install and test PV Author server software. A configuration parameters where changed in pvserver.conf file such as the host name of the server to be able to communicate with the web server and the video source.
Finally, testing was made to make sure that the server is able to stream A/V from a sample files available on the server (http://220.127.116.11).
PV-PC Author Software:
This is the actual Encoder software, typically installed on the computer system, which has the digital video source. From this program the bit rate and frames per second to be transmitted are determined among other parameters. Such parameters are influenced by the type of the wireless link is used to view the A/V.
PC Client Software:
This software are installed on the target computer system that needs to view the video, no configuration parameters are required.
Testing the system:
Over the next two weeks we will test this system using different wireless communication protocols, mainly CDPD and Wireless LAN Protocol. For these propose I did set up IPAQ 3650 H hand held device with a CDPD modem. Furthermore, I did install an Indoor wireless LAN. The testing will be preformed next week.