November 2006 TECO-WIS, Seoul 1 Definition of the Internet Network of networks –millions of smaller domestic, academic, business, and government networks –Uses TCP/IP protocol suite Carries various information and services, such as electronic mail, online chat, file transfer, documents of the World Wide Web. Internet and the World Wide Web are not synonymous: –the Internet is a collection of interconnected computer networks, linked by telecommunication media –the Web is a collection of interconnected documents, linked by hyperlinks and URLs.

November 2006 TECO-WIS, Seoul 2 Common Protocols allow Coexistence Internet can be used as: –an underlying technology for some components of the GTS in special conditions –as a backup to the GTS –as a complement to the GTS Communication Component Function GTSDelivery of time critical communication for weather, water and climate operations InternetCommunication for less critical requirements and possibly for large volumes of data

November 2006 TECO-WIS, Seoul 3 Telecommunication Options

November 2006 TECO-WIS, Seoul 4 VPN Concept

November 2006 TECO-WIS, Seoul 5 Virtual Private Networks (VPN) Create the equivalent of a dedicated private link using the Internet as a connection media

November 2006 TECO-WIS, Seoul 6 WIS VPN Pilot Project in Regions II and V (as of Sept 2006) Hong Kong India Iran Korea Oman Saudi Arabia Vietnam Australia Brunei Malaysia New Zealand China Soon established VPN-link with Japan Established VPN-link with Japan Japan Singapore 10Mbps (max) 2Mbps 4Mbps 512Kbps 2Mbps 1Mbps 100Mbps (max) 3Mbps 2Mbps 1Mbps Internet 100Mbps (max) 256Mbps (min)- 440Mbps (max)

November 2006 TECO-WIS, Seoul 7 File Transfers and FTP servers Uses File Transfer Protocol Can be used for dissemination or exchange of bulk meteorological data through Internet, GTS or other local/wide area networks Recommended for predefined users Efficient data exchange protocol Good for both push and pull configurations File Naming is important – see Man 386 Att II.15

November 2006 TECO-WIS, Seoul 8 FTP Server Implementation

November 2006 TECO-WIS, Seoul 9 Electronic Mail Uses the Simple Mail Transfer Protocol (SMTP) Complementary method of data input into the GTS –Should not be used to replace GTS data exchanges for mission critical components –Usually can not guarantee real time data delivery –Requires sites to collect messages (some examples: Washington, New Zealand, Tokyo, Beijing) –Requires a strong quality control at the collecting center as the collected messages often contain several typing or format mistakes Mostly a push mechanism May be used for notification (for example that a file is available for delivery while the file itself is placed on an FTP server) Excellent general communication tool Important entry point for virusses, worms and Trojan Horses Must deal with SPAM problem –Spamming is the abuse of electronic messaging systems to send unsolicited, undesired bulk messages

November 2006 TECO-WIS, Seoul 10 Implementation

November 2006 TECO-WIS, Seoul 11 Web Servers Based primarily on Hyper Text Transfer Protocol (HTTP) Used to make available various data and reports, available to users who request the information by downloading the various « web pages » (pull mechanism) Offers an intuitive approach to presentation of data and links between data elements Allows complex scripts and data management tools to be added Requires permanent connection to the Internet Requires careful and significant planning and maintenance –Weather data is updated very often –Demand for weather data can be very high –In large sites can become very complex

November 2006 TECO-WIS, Seoul 12 Web Server Implementation

November 2006 TECO-WIS, Seoul 13 Important Documents Manual 386, Attachment II.15 – Use of TCP/IP on the GTS (Revision 3, Sept 2006) Guide on Information Technology Security (Sept 2006) Guide on Internet Practices (Sept 2006) Guide on use of FTP and FTP servers at WWW centres (Sept 2006) Guidance on IPSec-based VPNs over the Internet (April 2004)