Re: [Pi3web-users] Basic questions

[Holger Z. <zi...@t-...>]

Hello Doug,

I try to give you an answer for each question, but for some of them
there's no unique answer. Treat the answers below as a short
introduction to each topic. Many, many books were written about it.
And I'm rather a software developer than a networking specialist.

1. How do I register my hosted site on the Web?

Normally you can engage your Internet Service Provider (ISP) to
perform most of the necessary steps. These steps also depend on the
location of the computer hosting your web site and the location of the
DNS servers:
- register an internet domain name, if not yet done. You must provide
the address of a primary and a secondary DNS server in order to perform
this.
- set up the DNS servers for the domain. There are DNS service providers
like dyndns.org (where I host DNS for pi3.org and pi3.net). Most ISP's
and some domain registrars provide DNS. DNS means 'Domain Name Service'
and this services resolve your domain name to an IP address, e.g. the
www subdomain to the address of the web server.
- router configuration. This means network address translation (NAT) and 
port mapping. You have to map your external IP address (which is in the
public range of your ISP) to the address of the computer hosting your
web site (which can be a private address in a LAN).
- web server IP configuration. The server needs to listen on an address,
which can be reached from the outside. This isn't necessarily the public
IP address but very often an address in a LAN. It is insufficient to let
the server listen on 127.0.0.1 or 'localhost' because this loopback
address can be reached only from the host computer itself. If the server
listens at address 0.0.0.0 it means it listens on all network interfaces
of the host and this is a good choice for many purposes.
- optional: virtual host configuration. Only required, if the web server
shall serve the contens of different sites (different by host name or
IP address).

2. I some how need a static address, right? How do I get this?

Basically the answer is yes. The topic is related to the 1st question.
It depends on your ISP connection, whether you get a static IP
address or not.
For a bigger organization or a company it is recommended to register an
own domain name, to have at least one fix/static IP address and to be
connected through a fast link to the internet.

3. What speed of computer would be necessary for me to get started?

The CPU speed isn't the critical parameter. A modern PC with >=1GHz
should be sufficient. But think about hard disks, which can be operated
7/24 without risk of damage, sufficient RAM (>512MB), at least 100MBit/s
ethernet connection...

These parameters depend on the load the system has to carry, i.e. how
much users do request content in parallel sessions.

Another point is to think about (high) availability of the components of
the system, e.g. a RAID array of hard disks (raid level 5).

And finally you should thin about backup/recovery or a failover solution
(could be a 2nd computer with the same software and data).

4. What phone line connection would be necessary for us?

2 MBit/s should be sufficient for smaller sites. But the required
bandwith has to be planned carefully. If you have too little, user
experience will be poor, if you have to much, you pay a lot of money
for unused bandwith. The parameters are roughly:
- the average number of user sessions in parallel
- the average content size (complex pages, many pictures, large download
   files?)
- the required user experience (latency)
- the user behaviour (ratio between requests and breaks)
- a peak factor for high load (2-10 times)

An example: To serve pages of an average size of 50kBytes to 5 parallel
users, 1 second latency and no breaks you need 5*50kBytes/1s. This is
250kBytes/s or 2MBit/s. This is a theoretical value without taking
ethernet packet loss or protocol overhead or etc. into consideration.

Bandwith requirements of other internet services (e.g. E-Mail) sharing
the line needs also to be considered, except the line is exclusively
reserved for accessing the web server from outside.

The external bandwith should also be in a meaningful relation to the
network bandwith the computer hosting your web site can serve.

5. What would I need other than what I currently have and pi3?

Unfortunately I don't know at all what you currently have. Anyway, 
additional components do partial depend on the type of the connection to
your ISP, e.g. DSL splitter box plus a DSL modem. Normally you will get
some or all of these components from your ISP. There are modern,
integrated devices, where DSL modem, router and firewall etc. is in the
same box.

If the internet line isn't directly connected to a PC but to a LAN you
will need a router handling the traffic between the WAN (wide area
network =ISP connection) and the LAN (local area network).

Finally I strongly recommend a firewall, which can be part of a router
or a standalone device or a software solution installed at the web host.

Optional are tools for logfile analysis, server monitoring (to get an
an alert, if the server is down)...

--
kind regards,
Holger Zimmermann