Hello, We also have a 'ping' based local monitoring program. We monitor response from our ISPs, national NAP's and DNS of local interest. See: http://acns.fsu.edu/~howard/ping2/today.html And you can get the source at: http://acns.fsu.edu/~howard/ping2/index.html It is table configurable to meet your local needs. Art. On Fri, 27 Jun 1997, David P. Maynard wrote:
Here is one alternative metric. I have a monitor program that measures single-packet ping times to name servers that are registered as in-addr.arpa authorities. I figure that people should put their name servers in a "good" position on their network and that they should always be up and running. My goal is to monitor O(1000) hosts at regular intervals (currently 10 minutes), but the list currently hast just over 400 sites. I started with the web access logs for a very large site with a worldwide user base, looked up the registered in-addr.arpa servers, then hand-pruned the list to weed out sites that block ICMP, etc. ICMP echo obviously isn't the best metric in the world, but it has low overhead and allows me to monitor a large number of sites without being disruptive. (Most people shouldn't mind a single ICMP echo packet every 10 minutes.)
It's been very interesting to watch the graphs as various backbones have glitches. For awhile I was comparing connectivity from a single-homed site to a 5-way multi-homed site. The difference in fault tolerance was dramatic. The next step is to combine some policy routing with some /24 network announcements that are only announced from one backbone to compare connectivity via MCI, Sprint, BBN, and UUNET. (Ie, run parallel copies of the monitor in an environment that simulates single-homed connectivity from each provider.) The results should be interesting, but I wouldn't want to claim that they represented anything more than a measure of connection quality from the particular sites where the tests were run.
At the moment, the tool and the data are proprietary since I wrote it for a particular client, but I'm hoping to get permission to release the data once there are some results that are closer to "research quality." (We have been collecting data continuously since early March.)
-dpm
-- David P. Maynard, Flametree Corporation EMail: dpm@flametree.com, Tel: +1 512 670 4090, Fax: +1 512 251 8308 --
Art Houle e-mail: houle@zeppo.acns.fsu.edu. Academic Computing & Network Services Voice: 644-2592 Florida State University FAX: 644-8722