Title: A New Architecture for Web Services at CERN
1A New Architecture for Web Services at CERN
- Alberto Di Meglio, Francois Fluckiger, Monica
Marinucci, Per Hagen, Alberto Pace
http//cern.ch/web
2Part 1 of 2
- The new Web Namespace
- Review of new Services
3Todays namespace
- http//www.cern.ch/
- http//wwwinfo.cern.ch/
- http//network.cern.ch/
- http//home.cern.ch/
- http//nicewww.cern.ch/
- http//wwwas.cern.ch/
-
4Is there a problem ?
5Is there a problem ?
6From the MAIL architecture
Translation Service
Generic address
Physical address
First.last_at_cern.ch
user_at_host.cern.ch
Global namespace
domain
Mailbox name
Physical Mail Server name
7The same for the WEB
Translation / Redirection Service
Generic address
Physical address
http//cern.ch/SiteName
http//host.cern.ch/path
Global namespace
domain
Physical Web Server name
Site Name
8Complete Duality Mail - Web
Mail address and mailing lists
Web address
Organisational Units
it-div_at_cern.ch
http//cern.ch/it-div
aleph-exp_at_cern.ch
http//cern.ch/aleph-exp
Individuals addresses and personal files
alberto.pace_at_cern.ch
http//cern.ch/alberto.pace
9 more duality
- Mail
- Mail Composing tools are unable to find the
physical server name from the generic address
first.last_at_cern.ch - given a users mailbox xxxx, the host
xxxx.mailbox.cern.ch represents the server
hosting the xxxx mailbox - Web
- Web Authoring tools are unable to find the
physical server name from the generic address
http//cern.ch/xxxx - given a sitename xxxx, the host
xxxx.web.cern.ch represents the server hosting
the xxxx site
xxxx_at_xxxx.mailbox.cern.ch
http//xxxx.web.cern.ch/xxxx
10Not limited to Central Servers
- MAIL Generic E-mail Addresses (xxxx_at_cern.ch)
can point to locally managed mail servers or even
to servers outside CERN - WEB Generic URL Addresses (http//cern.ch/xxx)
can point to locally managed web servers or even
to servers outside CERN
11What about www.cern.ch ?
- http//www.cern.ch and http//cern.ch are
equivalent - Users preferring the www.cern.ch syntax can use
it, the leading www. being optional.
12Will we still have broken links ?
- The new web redirector supports site aliasing
- Multiple / different names can be mapped to the
same physical site
- We can have
- Old names pointing to new names
http//cern.ch/cn-div -gt http//cern.ch/it-div - Descriptive names pointing to real
names http//cern.ch/it.division -gt
http//cern.ch/it-div http//cern.ch/Alberto.Pace
-gt http//cern.ch/pace - Site nicknames, easier to type http//cern.ch/it
-gt http//cern.ch/it-div - Existing hosts can be taken over by the central
redirector - http//mysite.cern.ch/ -gt http//cern.ch/mysite
13100 compatible with the existing infrastructure
- Existing servers integrates smoothly in the
namespace - No broken links / No HTML to modify
- The Web namespace becomes independent from the
physical server layout and it allows the
evolution of the existing infrastructure
14DEMO
- You can access the CERN Scuba club site using any
of the following URLs - http//cern.ch/subaqua
- http//www.cern.ch/subaqua
- http//web.cern.ch/subaqua
- http//subaqua.cern.ch
- http//subaqua.web.cern.ch
- http//subaqua.web.cern.ch/subaqua
- As in the browser, the prefix http//and the
domain name cern.ch can be omitted, a CERN user
can simply type subaqua to access the site
15Part 2 of 2
- The new Web Namespace
- Review of new Services
16With the new web namespace
- We are no longer bound to the all in one
server architecture. - We can differentiate Server OS, Web Server
software, File Storage and support multiple
solutions if necessary. - We can go beyond simple static HTML authoring and
open a wide set of new services - (as described in the next slides)
17Site Hosting
- Site hosting means offering disk space to store
web files and then make them available via http - Based on a pool of (cheap) servers to host web
sites of customer who do not want to maintain
their own server - Load balanced using the web.cern.ch subdomain
- Every web site has one (and only one) owner
responsible for the site content who can manage
or delegate the site security
18Site Hosting
- Sites can be physically stored on
- Central Web servers
- AFS
- NICE
- (locally managed servers)
- Flat Namespace (part of the CERN web namespace)
- http//(www.)cern.ch/sitename
- Subsites are possible but managed by owners of
upper sites - http//cern.ch/mainsite/subsite1subsite1 is
managed by the owner of mainsite
19Authoring interfaces
- Authoring interfaces (sites on the Central Web
Servers) - HTTP (PUT method) http//sitename.web.cern.ch/sit
ename - FTP ftp//sitename.web.cern.ch/sitename ftp//use
r_at_sitename.web.cern.ch/sitename - OSE Microsoft Office Server Extensions See
http//www.microsoft.com/office/ork - DAV Distributed Authoring and Versioning
(Foreseen) See http//www.w3c.org
20DEMO
21Whats the difference ?
22Site Registration Services
- Automated Site Registration and Creation Service
- Users can create/delete web sites or
registrations themselves - A moderator authority supervises all actions
- Users are authenticated on AFS or NICE and site
ownership is always checked
23Support for Authoring Tools
- Site management page editing tools
- Microsoft FrontPage
- Macromedia Dreamweaver
- Page editing tools
- Netscape Composer
- Other Microsoft Office Applications (Word, Excel,
PowerPoint, Access, )
24More Services
- Forms
- All sites in the central web servers are
form-ready - Users can create electronic forms themselves
- Databases
- All central web pages can be connected to
databases - Databases can be local Access files or remote
Oracle - Read and Write access
- Search services
- Both client-side (infoseek) and server-side
indexing - Complementary services
25Searching and Indexing
- Two distinct methods
- The Infoseek server indexes all reachable
documents. - Indexes also locally manages servers
- CERN global searches possible
- It takes 3-4 days before a page gets revisited
- Server-side indexing
- Instantaneous index update
- Very fast queries for subsearches
- Extended searches possible (hit count, client
addresses, whats new, ) - The Infoseek and the server-side indexing are
complementary services
26More services (2)
- Access Control
- ACL, IP address restrictions, external
authentication, password protected documents, - Secure connections (HTTPS, SSL)
- Available on all central sites by default
- Cascading Styles Sheets (CSS) and Themes
- We have now the necessary tools to make available
Corporate / Divisional look and feel policies - Document Source Control
- For sites authored by multiple persons
27Access Control Security
- Web Site Owners can manage access to central
sites - Access Control List
- Login forms and name username/password pairs to
authenticate unregistered users - IP addresses restrictions
- Password-protected document
28Secure connections and SSL
- Every Web page on the central Web server can be
accessed using HTTP or HTTPS - Web authors can choose which protocol to use
29CSS and Themes
- Cascading Style Sheets are supported (normal HTML
feature) - FrontPage Themes are supported for FrontPage
authors - Same functionality but does not require a
CSS-compatible browser - We have now the necessary tools to make available
Corporate / Divisional look and feel policies
30Source Control
- Every Site hosted on the central server can
activate source control for sites authored by
many persons simultaneously - Document source control available only to
Microsoft Office users only
31CGI-Interface and Scripting
- Every site on the central servers has a cgi-bin
directory - Standard CGI-Interface fully supported
- Scripting
- Supported interpreters .PL (Perl) and .ASP
(Active Server Pages). - Supported languages for ASP Vbscript, Jscript
and PerlScript.
32Conclusion
- The new namespace gives us independence from the
physical infrastructure and allows us to move
forward - An important set of pending requirements for the
web services will be addressed with the new
architecture - For more information
33http//cern.ch/web