domain.com IN A 192.0.1.1To access your server, browsers and other clients have to know how to find you. The Internet (including the World Wide Web) has set up global standards that allow all systems to work together and find every other computer on the Internet. These consist of unique IP addresses for every computer on the Internet, host names such as "www.starnine.com" so we don't all have to remember the IP addresses, and Domain Name Servers (DNS) which hook them all together.
IP stands for "Internet Protocol": the overall set of standards defining communications for the Internet.
TCP stands for "Transmission Control Protocol", which is how computers send messages back and forth.
TCP/IP is used to refer to Internet networking in general.
WebSTAR version 3 can also support multiple web sites on one server. For more information, see Virtual Hosts: Hosting Multiple Web Sites .
The Internet uses unique ID numbers called IP Addresses to identify each individual computer on the Internet.
These addresses are represented as four sets of 8-bit numbers (numbers from 0 to 255), with periods between them. For example, StarNine's main web page is at:
198.211.93.9
There's a hierarchy from left to right roughly organizing the entire Internet, so that some networks can contain other networks. The last number on the right is the host ID number: it identifies the individual computer.
To serve data from WebSTAR, you must get at least one static IP address for your server machine, to identify yourself to the Internet. You may have one already: check your TCP/IP control panel. If there's an IP Address filled in, write it down for future reference.
You can have more than one IP address for a single WebSTAR server: see Virtual Hosts: Hosting Multiple Web Sites .
If you don't have an IP address, you need to get one. Your process for doing so depends on your network connection:
If you dial up to your ISP at intervals, you probably have access to a set of shared, dynamic IP addresses . That's fine while you're browsing the Web or sending email, but it doesn't work for WebSTAR, because no one can find you. You must arrange for a more continuous connection to your ISP and get a static IP address.
If your network doesn't yet have TCP/IP access and you have to use a modem, you must either work with your Network Administrator to add TCP/IP support, or follow the instructions from your ISP to get a static IP address, and enter that in your TCP/IP Control Panel for your dialup connection.
Because numbers are difficult to remember, the Internet evolved domain names for organizations and host names for individual computers. These are the familiar names you see when browsing, such as www.starnine.com , ftp.apple.com , and so on.
To be exact, the first part is the computer's unique "host name", the second part is the "domain name", and the last part is the "top level domain". This section will explain each of these elements in detail.
The Host Name is the unique name for a computer within its domain. It's always the first element of a full name, and, with its domain and top-level domain suffix, creates the unique name of that computer on the Internet. For example, the StarNine website is www.starnine.com . "www" is not unique on the web, but it is unique within StarNine.
For example, the StarNine main web server is:
www.starnine.com
and the server running the search engine is:
search.starnine.com
Both of these are host names in the "starnine.com" domain.
Defining your server host name requires you to work with your ISP or Network Administrator: see Your Server's Host Name for details.
The middle part of the name, between the host and the top-level domain is the domain.
For information on getting a domain name, see Your Server's Host Name .
The domain can be an organization name, such as "starnine"; a product ("webcollage"); or any other word, ("searchtools").
Domains can include several levels of naming, usually getting more specific from left to right. For example, the host name www.ci.berkeley.ca.us has these elements:
Top-Level Domains (TLDs) are always the last element in a domain name.
In the United States, TLDs are divided by type of organization
Hosts with interesting top-level domains include rs.internic.net, www.nasa.gov, sims.berkeley.edu, and www.npr.org .
Some US sites also use the two-letter state abbreviation followed by the " us " country code, like the City of Berkeley, above.
Most non-US sites use a two-letter country code as their top-level domain. Examples include stairways.com.au , ibacom.es , and iph.fgov.be . A full list of official codes is available at:
http://www.bcpl.lib.md.us/~jspath/isocodes.html
Together, a host name, domain name and top-level domain will identify your WebSTAR server to the Internet.
You can have more than one host name for a single WebSTAR server: see Virtual Hosts: Hosting Multiple Web Sites .
If you are working within a larger organization, they probably already have a domain name. Therefore, the domain of your server will be the host name followed by the domain of the organization.
If you are independent, then you can register your own domain, and use it for your WebSTAR server. Your ISP should be able to help you register it. As of the time of this writing, the Domain Name Registry in the United States is run by Network Solutions, Inc. at:
http://www.networksolutions.com/
If you control your own domain, you can choose any host name you like. Common practice is to make the host name for web servers "www". Doing so gives information to people browsing the site, and lets them type in the name even if they don't have a bookmark. The DNS system will automatically route requests to your server.
While the host name is the name of your server, it must be included in the Domain Name system. Therefore, you'll have to work with your Network Administrator or ISP to register it.
If you're in an organization, your computer may already have a host name. If you think you already have a host name, you can use the IPNameTool application from the AG Group, included on the WebSTAR CD. Enter your IP address and it will look up the name for you.
If you don't have a host name, or you want to change the name, you should arrange to have the Network Administrator help you name your server according to organization policies. They will also register it with their DNS server.
You can use the WebSTAR web server to respond to several host names, even in different domains, which can share the same IP address. In this case, you must arrange for the DNS records for each host name (as described in the next section), and use the WebSTAR Virtual Hosts panel to specify the names and IP addresses (if appropriate). For instructions, see Virtual Hosts: Hosting Multiple Web Sites .
To link the host names and the IP addresses, the Internet uses a system called the Domain Name Service (DNS) protocol. DNS servers keep databases of these name-address combinations and work together to keep the system up to date.
For technical information, see RFC 1034 . The most authoritative book on DNS is "DNS and Bind", published by O'Reilly.
Your ISP or network administrator is probably running a DNS server. To enter your WebSTAR server into this system, you should request that your ISP or the network administrator make sure your server host name or names and IP address is in their DNS database. They will broadcast this information to other DNS servers across the Internet, and everyone will be able to find you shortly.
The A (Address) record is the vital link between the host name and the IP address. All Internet host machines must have an A name record somewhere in the DNS system.
To distribute your server requests among machines (if your DNS server performs load sharing), you may direct one domain name to several IP addresses.
The A name record contains the host name, class "IN" ("Internet"), the letter "A", and the IP address of the host machine.
mail.domain.com IN A 192.0.1.2
www.domain.com IN A 192.0.1.1
In the example above, the domain.com and www.domain.com host names both point at the same IP address, while the mail.domain.com host name points at another address.
For HTTP (Web) and email serving, you must also create Host name entries in the WebSTAR Admin application. You do not have to do anything special for FTP services.
The CNAME (Canonical Name) record is an alias, much like a Macintosh alias file: it points to another host name. The DNS administrator may use CNAME records to define virtual host names.
A CNAME record is just an alias, so don't try to add any more entries to that host name record, but put the other information in the A Name records instead. They are generally used in the case where you might be pointing to a host on another network that has an A record in another DNS system, for example, if your ftp server was actually located on a different network and some other DNS administrator was apt to change the A record for that host without notice.
The CNAME name record contains the host name which is the alias, class "IN" ("Internet"), "CNAME", and the real host name for the alias to point at. For example, this entry:
directs all requests for the host name ftp.domain.com to the machine which hosts www.domain.com .
Never put the CNAME on the right side of a DNS entry: always use the A (authoritative) name on the right.
MX (Mail Exchange) records specify whether the host is running an email server or messages for this host should go to another mail server machine. For more information, see DNS Servers and Mail Hosts .
If your DNS server goes offline for any reason, links to your site will fail and email will bounce. Therefore, the domain registries generally require you to register at least one alternate DNS server. You should make sure that the secondary servers are located on other networks (so local problems will not affect them) and have all current information. Your ISP or institutional DNS administrator can help you to update this information. This is particularly important if you are running WebSTAR Mail.
To make sure that your DNS entries are correct, you should check them periodically.
There are two free online forms for checking DNS status. The British ISP Demon.net has a slightly different form at:
www.demon.net/external/ntools.html
And the Men & Mice company provides a form at
http://us.mirror.menandmice.com/cgi-bin/DoDig
If you are independent or have a cooperative network administrator, you can run your own DNS server. This allows you to add Virtual Domains quickly, and to alias several IP Addresses to one domain name, for load balancing, mirroring and other purposes. There are several Mac OS DNS servers available, for information, see:
www.starnine.com/extendingwebstar.html
WebSTAR Server Suite includes a Plug-In to work with QuickDNS from Men & Mice, which provides local DNS services and server load balancing.
The TCP/IP standard defines port numbers which allow one machine to serve several different kinds of data, such as HTTP, HTTPS, FTP, SMTP, POP and so on. The default services are specified in the range 1 to 1000.
The WebSTAR Admin application and Plug-In also use ports to communicate for remote administration. The default number for each server is the port number of the server + 1000 .
WebSTAR allows you to override the default Web request port numbers: see HTTP Port .
You may notice attempts to use port 1080: this is also used by the network security protocol SOCKS, and is not necessarily an attempt to break into the WebSTAR Admin.
Firewalls are not required, but they definitely improve server security.
If you have a network security firewall in your company, your machines are probably limited to serving TCP requests from within your company. If you want to serve the Internet rather than an Intranet, you will probably have to ask your network administrator to open "holes" in the firewall for the appropriate ports on your WebSTAR server. Otherwise the firewall will refuse all URLs for your server from outside your company on those ports. WebSTAR Admin also communicates via TCP/IP. Therefore, to administer a WebSTAR server remotely, you must also have a hole in your firewall for the Admin application port ( 1080 by default).