Milestone No. 2-3 completed
Date: 30 October 2000
1.0 Deliverables
There are 6 major
objectives in Milestone 2-3. Comments
on each of these objectives are given below:
1.1 Technical Systems (equipment)
assembled and installed at the headend and 10 schools Done
A Norpak Broadcast Encoder was installed in the Master Control Room at the Knowledge Network (KNOW) and connection made to add data to the video. A TCP/IP data connection was made to the SchoolWeb Encoder through a dedicated ISDN line connection. Later, a high-speed connection will also be tested.
The Encoder was tested with data on all available lines in the Vertical Blanking Interval (VBI) (lines 10, 11, 12, 13, 14, 15, 16, 19 and 20). Other lines (17, 18 and 21) are reserved for TV test signals and caption data.
The inserted data is recovered from the received television signal and cached (stored) in files on school servers.
Caching servers have been installed at the following ten (10) schools:
|
|
School |
Location |
#
Students |
#
Computers Connected to SchoolWeb Server |
|
|
Secondary
Schools
|
|
|
|
|
1. |
Gladstone Secondary |
Vancouver |
1500 |
120 |
|
2. |
Revelstoke Secondary |
Revelstoke |
650 |
46 PCs, 64 Macs |
|
3. |
Boundary Central Secondary |
Midway |
224 |
125+ PCs, & Macs |
|
4. |
Nakusp Secondary |
Nakusp |
263 |
46 PC’s |
|
5. |
Burnaby South Secondary |
Burnaby |
2650 + 250 staff |
500+ |
|
|
Elementary
Schools
|
|
|
|
|
6. |
Fort Rupert Elementary |
Fort Rupert |
122 |
15 PCs |
|
7. |
Big Eddy Elementary |
Revelstoke |
110 |
32 Macs |
|
8. |
John A. Hutton Elementary |
Grand Forks |
360 |
80 Macs, 5 PC’s |
|
|
Special
Schools
|
|
|
|
|
9. |
Robson Community School |
Robson |
175 + Community |
35 PCs |
|
10. |
Port Hardy District Office* |
Port Hardy |
< 1000 |
< 200 PCs, + few Macs |
* This office Server is a proxy for:
North Island Secondary school, 500 students, 100+ PC’s – via T1 line
Port Hardy Secondary School, 500 students, 100+ PCs – via T1 line
Woss Elementary School, 60 students, 12 PCs – via slow wireless
This initial group of schools completes the undertaking under the CANARIE contract, but it is anticipated that further schools will be added (up to 19) to test other caching concepts.
The list above indicates that we have a variety of sizes of Secondary and Elementary schools from which to gather information. This will allow us to test whether small and large schools benefit equally or differently from caching. There are also some special tests to be made regarding:
(a) Port Hardy District Office, is using its Server as a Proxy server for two secondary schools, each connected by a T1 (1.544Mbps) link, and an elementary school connected by a slow link.
(b) Robson Community School, which allows extensive use of their system by the community during non-school hours.
(c) Boundary Central Secondary School, which carries out an extensive distance education program, and could possibly use caching to a greater extent for distance education students.
At each location there is a connection to a cable television service. The PC/TV decoder card in the server is set to receive any data from the KNOW signal, and pass it to the cache.
Caching is done both by the PLNet data line connection, and by broadcast means. Both ‘Dynamic’ and ‘Policy’ caching is employed.
1.2
Operations Group
completes headend and school initial software, to activate the initial service. Done
The software development team completed SchoolWeb V1.1 of the software for release on the 10 installed servers.
The major development focus was getting a Broadcast Caching System developed that would work seamlessly with a Proxy/Caching server on each of the SchoolWeb Servers. Each of the SchoolWeb Servers operate under the Linux Operating System. Two Proxy/Caching servers that operate under the Linux Operating System were considered. One was Cuttlefish and the second, a more widely used and popular server, called Squid. Cuttlefish’s specifications show that it had the added advantage of having features of adding files to Cuttlefish cache on command. No such feature existed with Squid. Due to the added features of Cuttlefish it was initially selected.
We carried out extensive testing of the Cuttlefish server and found that Cuttlefish had a lots of bugs associated with adding files to the cache. Considerable time was spent cleaning up the Cuttlefish code, but eventually we decided that the inherent instability of the program and the number of bugs in the product would not make it stable enough for the School Environment. We needed a Proxy Server that we could rely on.
At that point in time we decided to switch to Squid, which we had previous experience in using. The major weakness of Squid was that it lacked the feature of adding files to the Squid Cache. The decision we were faced with was either to modify the Squid Code and add the feature of adding files to the Squid Cache directly, or to fool the Squid Server into adding the files to the Squid Cache by pulling the files by other means.
The decision was make to fool the Squid Server into adding broadcast files to the Squid Cache. No changes in code to the Squid Code were made, allowing us to continually upgrade to newer versions of the Squid Server. We created two programs called aiicpd (advanced interactive internet caching protocol daemon) and aiihttpd (advanced interactive hyper text transport protocol daemon) that emulated an Internet Caching Protocol Server.
Below is show a simplified description of how files are automatically added to the Squid Cache without modifying the Squid Server in any way:
1) A new file arrives via the broadcast signal and it is saved on disk.
2) Next a command is sent to the Squid Server to purge the newly arrived file from the Squid Cache if it exists. If the file exists in the Squid Cache it is purged from the Cache else it replies that no such file exists in the Squid Cache.
3) Next the aiicpd program is triggered to create a list of files on the new disk cache.
4) Next a request is made to the Squid Cache for the newly arrived file.
5) Squid then makes a request to the aiicpd server for the newly arrived file.
6) If the file exists on the aiipd list, it answers Y to Squid, else it answers N to Squid. If the file does not exist on the aiicpd list then Squid gets the file from the Internet (11).
7) Squid then requests the file from the aiihttpd server.
8) aiihttpd transfers the file to Squid.
9) Squid adds the file to the Squid Cache.
10) aiihttpd deletes the file from the new disk cache.
In Milestones 6 the aiicpd and aiihttpd programs will be upgraded to allow for dynamic requests of files from the Headend and the files being delivered to the Squid Cache via the Broadcast signal. This way a very low speed line can be used for Web Access and the Broadcast signal used to deliver the information. All the associated SchoolWeb server(s) could then cache the information.
Since the files are sent to the
SchoolWeb server(s) via a broadcast signal there is no TCP/IP ACK/NAK
capability for re-sending bad packets.
Therefore, we developed an extremely robust FEC algorithm that checks
for the validity of each packet of information transmitted via a video line. Currently each video line can carry 33 bytes
of information. We use three bytes for
packet header and two bytes for checksum.
The two bytes of checksum can detect one and two bit errors and also
correct one and two bit errors. The
industry standard FEC can only correct one bit error and detect two bit
errors. In the next milestone we will
be upgrading the FEC code to provide bundled FEC that will allow for the
replacement of completely lost packets.
Without any error correction our Bit Error Rate (BER) is 10-6. With error correction we targeting a BER of
at least 10-8 or better.
In addition, SchoolWeb V1.1 consists of:
·
Linux Operating System – RedHat Linux Version 6.2 (Linux Kernel 2.2.14)
·
High-speed local Area Network – the Server connects to internal PC’s at an Ethernet
LAN speed of 100Mbps
·
Proxy/cache Server for high-speed Internet access - Users can access information via Satellite, cable,
ISDN, ADSL or dial-up telephone line.
The first request for an Internet site caches the file for immediate
access by others. Broadcast Cache Server allows for web based information to be
broadcast to the Proxy/cache Server via a TV channel broadcast or via Satellite
down link. The web- based information
is added to the Proxy/cache server cache and operates seamlessly with the
regular proxy cache. The cache server
is integrated on a nightly basis and new web information is sent to the cache
on a continual basis via the broadcast feed.
Furthermore, teachers can request websites that they want to be added to
the cache via a Broadcast feed.
·
A DNS Server
for caching domain names is provided to increase Internet access speeds.
·
Redundant on-line system – at least two high-speed hard drives are
provided. If the primary disk is lost,
operations can immediately resume on the back-up system without loss of time
and work
·
Automatic power-down and power-up on power failure – an uninterrupted Power Supply (UPS) is provided which
provides continuous power for the Server to shut down properly on power
failure. When power is restored, the
Server automatically fires up again to resume normal operations
·
NFS Server –
Network file server is provided to permit file sharing between clients and
servers on the Internet
·
Print Server –
a network printer can be attached to the Server to be shared by all users
·
Installation, set-up, training and optimization of the Server is included or provided remotely.
·
Remote maintenance and Problem Alert - Server continually monitors all services. All problems are reported to the headend
server. The headend server also
continually monitors each of the remote servers to insure that each of the
servers is up at all times.
1.3 Training of school personnel
completed for 10 installed schools Done
As each school installation was planned, a list of our installation requirements was sent in advance to each school so installation time could be reduced. This information request included such items as: IP, Gateway and DNS addresses, domain names, power utility and environmental requirements, ASCII file names of users, and details of computers, networks, any security in place, and school policies.
On the average, the installation of server and UPS, connection to utilities, labeling, set-up and training of staff (on the server only) took only about one-half day. Much greater time was taken showing school personnel how to set up their individual client computers, and harmonizing our server to work with other installed networks and security software.
Caching was demonstrated immediately, by noting the time to download a large file for the first time, and then noting how quickly it was available for the second user (and all subsequent users). The difference was dramatic. The first download might take minutes or more (depending on the size of the file requested), while the second request was instantaneous.
During the training program, we emphasized the benefits of policy-based (pre-planned) caching, and encouraged Principals and operating staff to demonstrate to teachers how much time can be saved for their students, if they request the necessary Web sites in advance.
We also had an opportunity to go through our preliminary documentation on the setup of clients with many school staff, and found a number of areas where improvements could be made.
1.4 PLNet internet connections made
to KNOW and schools. Done
PLNet internet connections are made to KNOW via a 10 Mbps fiber link from a central router at Telus, and Harbour Centre. Connection to BCNet is made at Harbour Centre. PLNet advises that the connection from BCNet to Ca*Net3 will be made in the near future. In addition, Advanced Interactive Inc. has installed a dedicated Telus ISDN line to its encoder for continuous data transfer.
PLNet connections have also been made to all schools under our test program. Most connections are at 56 Kbps, while a few are up to T1 rates.
1.5 Evaluation Committee put in
place, and telephone conversations held. Done
As part of the initial training program, each installed school was asked to assign on or two persons to be assigned to an evaluation Committee. The Evaluation Committee is to provide ongoing critical review of the use and operation of the caching server service, and any related services. The objectives of the Caching Program were reviewed and committee members asked to document any results and concerns as the project proceeds.
The following persons are on the Evaluation Committee:
|
|
School |
Member |
|
|
Secondary
Schools
|
|
|
1. |
Gladstone Secondary |
Philip Arnold, Computer Science Teacher |
|
2. |
Revelstoke Secondary |
Ann Cooper, Superintendent Earl Woodhurst, Technical support |
|
3. |
Boundary Central Secondary |
Walter Osalleme, Principal Autumn Abrams, Technical support |
|
4. |
Nakusp Secondary |
Ernie Knecht, Teacher Alistair Skey, Technical Support |
|
5. |
Burnaby South Secondary |
Jeremy Meharg, Technical support Trevor Schofield, Librarian |
|
|
Elementary
Schools
|
|
|
6. |
Fort Rupert Elementary |
Malcolm Fleeton, Principal |
|
7. |
Big Eddy Elementary |
Anne Cooper, Superintendent Earl Woodhurst, Technical support |
|
8. |
John A. Hutton Elementary |
Michael Strukoff, Principal Autumn Abrams, Technical support |
|
|
Special
Schools
|
|
|
9. |
Robson Community School |
Michael Balahura, Principal Peter Repin, Technician |
|
10. |
Port Hardy District Office |
Gary Doi, Superintendent Steve Gray, District Administrator - Technology |
In conversations with each of the Evaluation Committee members, the following views were recorded:
1. Gladstone Secondary School
Philip Arnold – (604) 713-8288
· Phil was complimentary about the server and its facilities.
· He had no particular comment on caching except to say that it appeared to work well. He noted one problem pointed out by either he or Danny Dedios (pager (604) 252-7918) which was that when students are logged on to SchoolWeb they can’t see the Gladstone web site which is on the NetVista machine.
· Our server is much faster than the IBM Netvista, so there was a suggestion in the District that the Netvista’s be replaced with our server.
· Another comment was that there is no screening of bad Web sites on our system. I said that we relied on PLNet to do this. But since Gladstone is connected via Rogers cable, I wonder if this works for them? I told him of an additional table lookup of bad sites that Burnaby was constructing. We should follow up with him on this.
2. Revelstoke Secondary School
Big Eddy Elementary School
Ann Cooper (250) 837-2101
· As far as she knows the equipment is working well
· Earl Woodhurst has recently informed her that the system seems to have slowed down in the past few weeks. She asked that we look into this. Karim please examine the Logs of these servers.
· Regarding the possibility of a new purchase, the decision will not be made for another month or two.
Earl Woodhurst (250) 837-2173 or 837-8759
· Earl has an issue with bandwidth utilization. He was looking at some statistics of his which indicated that the proxy did not seem to be as useful as he had hoped. Starting on Sep 21 he gave a class assignment that was based on 5 sites: McLeans Magazine, Sam the Record Man, Schoolnet and two others. The system was so slow that he abandoned the project. We should look into this and find out the reason for his delays.
· In Big Eddy, he reported that the proxy server was temporarily turned off. Lets check on this.
3. Boundary Secondary School
John A Hutton Elementary School
Autumn Abrams Cell:(250) 442-6010
· The situation remains much like it was when we left the sites.
· Midway is not fully implemented, since they are expecting new computers to arrive, and would do the upgrade then. The 486’s are slow, and the new Pentiums will improve performance.
· At Hutton, the Mac’s can not see the SchoolWeb server.
· Autumn pointed out that we were going to provide her with 2 additional NIC cards so she could set up a firewall at both locations.
· A check of the Logs at these locations will likely show little activity in the past few days.
Walter Osalleme (250) 449-2224
Michael Strukoff (250) 442-8275
· With this in mind, I decided not to call Walter Osalleme or Michael Strukoff, the Principals of the 2 schools, since there would be little to report.
4. Nakusp Secondary School
Alister Skey (250) 265-3656 (True North)
Ernie Knecht (250) 265-3668
Kees Vanderpol, Vice Principal (250) 265-3668
· Alister stated that he had not had a chance to go back to the school to finish the set up of clients.
· Apparently, the school buys services from True North when they need them, and the school has very little on-site capability. I left a message for the Vice Principal, Kees Vanderpol to see if he can spare some money to get some help to get all the clients connected.
· Erie Knecht, (teacher) was going to try to set up the clients (Rayhman spent some time with him), but he is very nervous about making any changes. I am awaiting a call from him to see if we can provide the support he needs.
· Kees Vanderpol, Vice Principal was not too helpful. He does not want to have much to do with computers. He did mention that the School was out for bids on servers and computers, and I asked that their purchasing group put us on the bidder list and send us the documents. He suggested that I deal with Alister and Ernie.
5. Port Hardy District Office
Fort Rupert Elementary School
Steve Gray (250) 949-6618 x 241
Gary Doi (250) 949-6618 x
· Steve is in the process of setting up Woss Elementary, North Island Secondary and Port Hardy Secondary Schools to be served by the SchoolWeb server at the District Office.
· He lost one technician, so things have been slower to be implemented than he expected.
· Steve is currently setting up user accounts, and harmonizing our server ID’s and Passwords with other systems. This has caused some slowdown. Caching is working very well.
· There have not been any problems at Fort Rupert. It is working very well. He reminded me that, since the proxy works in the background, users are no likely to recognize that the system has improved, and will likely not attribute any improvement to the server. Our Logs should tell the real story. I told him that we would share this information with him, and show him how to get information from the monitoring system.
Malcolm Fleeton, Principal (250) 949-6518
· Malcolm said that he noticed that Internet access is much faster than before, and that he would work toward promoting ‘policy-based caching’ with teachers
· Overall the system is working well
· He is now going to set up email for all students
6. Burnaby South Secondary School & School for the Deaf
Jeremy Maharg (604) 893-0446
Trevor Schofield (604) 664-8560 x2219
· Jeremy is ready to set up all users for the proxy server, but is held up by Telus who must give us an entry through their firewall
· Trevor Schofield has agreed to assist us to set up a look up table of sites that will be restricted from access over the Internet.
7. Robson Community School
Peter Repin (250) 304-9238
Michael Balahura (250) 365-5922
· The server is working very well
· The computer lab is fully set up and functioning
· Peter is starting to train some of the teachers
· The school is having an official opening on Nov. 24 with the Community
· Michael reported that it seemed to take a long time to get set-up, but now things were working very well. He suggested that most of the problem was from their end
· Peter suggested that they would like to consider using our server for Stanley Humphries Secondary School in Castlegar.
· No further follow-up required for now.
With travel and living costs being high, and difficulty getting a representative group together to meet face-to-face, it is anticipated that most, if not all, of the Evaluation Committee meetings will be held by telephone conference. However, if the budget allows, we may try to schedule one face-to-face meeting during the summer of 2001.
1.6 Contact made for co-operation with
other technical resource groups such as Telesat and IDC. Done
Telesat is carrying out a similar caching project to SchoolWeb; except that they are concentrating on satellite delivery both to the School District and schools, while AIC is concentrating on TV broadcast delivery, primarily to school servers.
Some of the software problems in aggregating data at the central cache delivery point, having it pushed to the delivery system and recovered at the school caching server, are common to both projects. Thus, it is useful for the two groups to be helpful to each other where possible.
Through the encouragement of CANARIE and the fine rapport between company representatives, sharing of software and hardware items has taken place and is continuing.
AIC has also been in touch with International Datacasting Corporation (IDC), a company who has provided Integrated Satellite Receiver-Decoders (IRDs) to the Telesat project. AIC intends to set up a test system at our offices to test our software to send data on the satellite delivery system, and to understand the benefits of this system as a backup for some schools where broadcast reception may be impaired. The cost of this system will be supported within the existing equipment budget.
Contact has also been made with StarChoice, who deliver the KNOW TV signal via satellite to cable company headends. Together we are seeking ways to ensure that as many lines as possible in the TV signal VBI are transmitted and received. Later, we intend to try another encoder and MPEG-2 scenario, which will allow data to be encoded and decoded on many other lines normally used for video.
2 Schedule ( see revised Gantt Chart)
The following are comments on our schedule of progress versus our original Statement of Work:
1. Equipment systems for the headend and 10 schools required by the CANARIE contract have been installed and are operating. Assessment of school requirements will continue into December as suggested in the revised Gantt Chart. Additional equipment may be added as experience dictates, but is not expected to be anything that can not be accommodated by the upgrade budget.
2. Version V1.1 of the Phase 1 operational software has been completed and installed on both headend and school servers.
3. Training of all School personnel is completed. Additional training may be required as software modifications and new features are released.
4. All interconnections have been made, except for PLNet to CA*net3, which is scheduled for sometime this fall.
5. The Evaluation Committee is in place and is providing feedback to the AIC team.
3 Budget
3.1 Comment on the budget status of the project (see revised budget sheets)
1. Direct Labor
The costs incurred for Direct Labor are quite close to the revised budget figure for the milestone period. There has not been any change in personnel.
2. Consultants/Sub-contractors
The total cost of Sub-contractors exceeded the revised budget figure. This was as a result of adding 3 new subcontractors.
· Zuzana Kriskova was hired to design and setup the software that performs statistics on the performance of the SchoolWeb servers. She will manage software that will gather information daily from the school servers (automatically), and combine those statistics into weekly summary files, for analysis and display in table and chart form.
· Square Sphere Computer Consulting, Rahman Lakhani, is assisting in the setup of servers, and installation of systems in the field. He has many years of experience in setup and maintenance of networks.
· DBS management Ltd., Nizar Ryani, has been hired to assist in the set up and technical debugging of headend and school servers, and providing a help-desk function for schools.
3. Travel and Living
Up to now, we have been able to drive to the southern school locations to keep the cost down. However, that situation is about to change, as we are now facing more expensive travel and living costs for installations in the next nine remote schools. Consequently, our travel expenses are well below expectation; but this will be corrected in meeting the next milestone (4).