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6. Other Protocols

6.1. IRC - Internet Radio Chat

Pretend you've got a CB radio, with "handles," 10-codes, many channels to pick from, and then let it use text rather than voice transmission.

IRC is "superior" to genuine CB Radio in that it doesn't provide garbled transmissions (beyond spelling mistakes, and messages that are genuinely incoherent!), is not limited by geographic considerations, and provides something of a record that makes it a little easier to follow conversations that have been going on.

It's really quite valuable when they hold a revolution in Moscow, as you can potentially get play-by-play details of what's going on.

Unfortunately, at least 90% of the time it's a simply stupendous timewaster that seems populated by people who can neither spell nor type correctly, but think that they're k00l d00ds.

It also appears that a wide set of infrastructure has grown up surrounding the issue of how to "control" a particular IRC channel against "opponent hackers," which seems to me to defeat the purpose of having a public channel.

And I get the impression that the primary use of it these days is to allow people to "safely" talk dirty whilst thinking they remain anonymous. There seems to be a whole lot of paranoia around about "Internet chat rooms" being a place where sexual predators seek out targets. That is hopefully mostly paranoia, with minimal reality to back it up. But who knows...

6.2. LDAP - Lightweight Directory Access Protocol

The Lightweight Directory Access Protocol (LDAP) is a protocol for accessing online directory services. It was initially used as a front-end to X.500, running directly over TCP, but can also be used with stand-alone and other kinds of directory servers.

6.3. Searching for Host Information

If you are suffering from spam problems, or other more sinister problems, you may wish to find more information about who's behind a particular Internet host. Here are some relevant tools:

6.4. DNS - Domain Name Services

6.5. DHCP

Defined in RFC 2131, Dynamic Host Configuration Protocol indicates a way for hosts to ask a central server what configuration, notably including IP addresses, they should use.

Commonly used is ISC DHCPd.

It is common for routers to include a DHCP server, but I have set up a failover-aware configuration on a couple of my favorite servers at home; see DHCP Failover for instructions as to how to set this up.

6.6. Alternative Namespaces

There is not universal agreement that ICANN is the ideal body to manage domain names. (That may be putting it mildly!) As a result, there are some folks running an " alternative" namespace resolution scheme. Some of them might be a little kooky...

6.7. Provisioning Protocols

6.8. Port Security

Do you know where your ports are?

There are many Unix system services that typically are run as root for the sole reason that they control ports with ID numbers under 1024.

This is a dumb thing. Sendmail has been noted for having security holes due to the complexity of its configuration; the threat is magnified by the fact that it also typically has to run as root. Qmail was specifically written to not run as root, and works very well as a Sendmail replacement.

Moreover, this port requirement is only enforced on Unix systems, which means that it doesn't provide any real authentication e.g. - the fact that a service is provided on port 441 doesn't necessarily mean that the service is "privileged" in any way on its own host and thus even slightly trustable.

In short, services that can be run without root access ought to be.

6.9. Security Servers

NEC's Socks Server can be used to set up "secure" data channels between computers. It is most often used to help implement firewalls.

There is a lot of software available for securing communications by cryptographic means.

6.10. Silly Protocols

Quite commonly, really interesting new protocols are released on dates resembling the first of April. Few such protocols are implemented, with RFC 1149 as the one so bizarre that a computer club and a pigeon club got together to make it work...

6.11. FAQs - Frequently Asked Questions

6.12. i8n Encodings

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