Standards and Tools for Computer Network Diagrams?

_kabel asks: "Recently I've been asked to draw a map of my company's computer network. Gathering the data to do this isn't the problem though - it's drawing it all. This is no easy task, as it contains hundreds of hosts in many locations around the world, linked together with quite a variety of methods (modem, ISDN, ADSL, VPN over Internet and more.) So I have two questions: (1) Are there any standards on computer network diagrams (i.e. the symbols used for the various devices and connections) and (2) are there any tools already available to assist in this?" I know Visio has the capabilities and the symbols to do this, but what about the free-software diagramming tools?

Comments

Cheops and Cheops NG

[Seth Cohn]

http://www.marko.net/cheops/

Cheops is an Open Source Network User Interface. It is designed to be the network equivalent of a swiss-army knife, unifying your network utilities. Cheops does for the network what a file manager does for your filesystem.

And then:

http://cheops-ng.sourceforge.net/index.php

Cheops-ng (cheops next generation) description:
Cheops-ng is a Network management tool for mapping and monitoring your network. It has host/network discovery functionality as well as OS detection of hosts. Cheops-ng has the ability to probe hosts to see what services they are running. On some services, cheops-ng is actually able to see what program is running for a service and the version number of that program. Take a look at the screenshots page for a detailed look at some of the features of cheops-ng.