In the last year there was a lot of Internet traffic at the MAP Data Centre. On average, the MDC had 523 request per day or 190'685 accesses in the last year (counting each single access to a document or image in the entire MAP area). Figure 1 shows the daily traffic in the period March 1, 1997 to February 28, 1998. The minimum was 28 and the maximum 1943 accesses per day. In the MAP member area, the MDC had 76 request per day or 24832 accesses in the last twelve month. Here, the minimum was 0 and the maximum was 1023 accesses per day. In the public as well as in the member area you can recognise the weekly structure with working days, weekends, and holidays.
In the last twelve-month period, there were 7183 different workstations which accessed the MAP Webserver at least once. If only workstations with more than ten accesses in this observation period are counted, we obtain 1912 accesses. In the MAP member area, there were 362 different workstations with at least one, and 123 with more than 10 accesses. With the current number of 77 MAP accounts, it seems that some users use different workstations or - what would be worse - they share their accounts. We want to remind the account holders that any sharing of a personal account represents a violation of the agreement signed! For details, please refer to the MAP access policy (/map-doc/DataAccessPolicy.htm).
In the MAP member area there were 12'356 downloads of radar, satellite, and quick-look images. The number of requests to the Oracle database was 5232 in the public and 4561 in the member area. There was a dozen workstations with more than 4000 accesses in the last year.
Figure 1. Web traffic at MDC between March 1, 1997 and February 28, 1998.
On the information page "MAP Database contents" you will find information about the MAP Database contents in detail. In the surface data contents tables, we added the new service "Available Stations". The new row "Available Stations" contains a link to the station information page for every MAP season and episode. Figure 2 shows the table with the new service.
The following information of each station is available: name of station, internal and MAP number of the station, country, latitude, longitude, height, provider, and number of records. The "record number" field contains the number of stored records in the MDB. With this information you are able to determine the time resolution of measurements of each station.
To find the time resolution, you have to divide the number of records by the number of days of the season or episode. If the number of records of a season is very low (<100), you will get only data of the episode which is part of the season. Do not confuse the information you find here with the information stored in the station table; the newly included information refers only to the stored data in the MAP database. General information for each station is still found in the station table, irrespective of data stored at MDC.
Figure 2. New Service "Available Stations" in the MAP database contents
In the next month we will migrate our MAP database from Oracle7 to Oracle8, and Oracle Webserver 2 to Oracle Web Application Server 3. The reason for this migration is an announcement by the Oracle Swiss Customer Support Service in its Technical Newsletter I/1998: Oracle strongly recommends that all customers upgrade to Oracle 7.3.4 as soon as possible in order to obtain error correction support for a maximum period for Oracle7. However, already in June 1997, Oracle released the next generation of its RDBMS/Server, namely Oracle8. Therefore, the MDC decided to migrate from Oracle7 directly to Oracle8 without including an intermediate upgrade-step. The direct migration to Oracle8 will consume more or less the same amount of manpower as an upgrade to the latest Oracle7 version, however, with the migration we profit from a better and longer lasting support by Oracle in the next years. Furthermore, now is the last possible chance for such a change before the beginning of the MAP GOP; during GOP there will be no manpower available for such exercises.
As a first step, the MAP Backup Server will be migrated, afterwards the main MAP Server. During the migration phase there will only be short interruptions either on the MAP Server or on the MAP Backup Server. For the Oracle database gate, we will have to recompile all programmes because the new Web Application Server has a different internal structure. The status of migration will be published continuously in the MAP News at both MAP Web sites ( Newssheet and Newssheet). If the main MAP Web site cannot be accessed, please check the MAP Backup Web site for more information.
The good news for the users of the MAP Web: Nothing at all will change, all the changes are MDC internally. We are confident that the only signs of the change-over will be short, occasional interruptions in service.
We shall make every reasonable effort to test as many links as possible in the MAP document area. However, we do need also your feedback! Please report any interruption of external links as well as of links within MAP Web pages. We cannot fix problem of which we do not know!
Once more: We welcome any comment, critic, suggestion, or even applause. We certainly will not be able to fulfil every wish of MAP data users, but we are always willing to seriously look into any recommendation. Remember, the MDC is serving you, however, in order to do so successfully we do require a minimal feedback in order to set our priorities.
