We just finished deploying a Snort IDS system on our network. The task of doing so was well worth the effort, and quite a bit of effort and resources were needed for our deployment. Due to the fact that we have a sustained 5Gbps of traffic to monitor in our Tampa data center alone, a simple server running Snort was just not going to cut it and rather than deploying off of our core routers in Tampa, which would catch inbound and outbound traffic, we decided after our testing that placing our tap points on our core routers was just not going to be sufficient due to the amount of abuse we saw in testing between customers in our facility. We decided to build a single server for each of our distribution switches at all of our locations that would communicate to a central server running the ACID console. This deployment has allowed us to gather so much information about what *TRULY* is and has been going on, that we wonder why we didn’t do this sooner. Please keep in mind that there are many right ways to deploy an IDS system, however only one is really going to fit *most* of your needs initially. With some time, patience, and quite a bit of caffine, you should be well on your way to dropping your abusive traffic on your network. Good luck to you! -- Jordan Medlen Chief Network Engineer Sago Networks _____ From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Drew Weaver Sent: Thursday, June 09, 2005 11:46 AM To: nanog@merit.edu Subject: Using snort to detect if your users are doing interesting things? Howdy, I am not sure if this is the proper place, if not I’ve noticed you guys know what to do so I’ll put the fire retardant suit on now. Recently due to growth we have seen an influx of “different” and “interesting” types of characters ending up on our network. They like to do all sorts of things, port scan /8s spam, setup botnets with the controllers hosted on my network.. etc. I’m wondering what is the best way to detect people doing these things on my end. I realize there are methods to protect myself from people attacking from the outside but I’m not real sure how to pinpoint who is really being loud on the inside. I did have one somewhat silly question.. if you look at the statistics of a Fast Ethernet port, and it is doing both 2000 pps out, and 2000 pps in (pretty much equal in/out) but hardly any bandwidth at all can anyone think of a single application that would mimic that behavior? Sorry if this is elementary network school knowledge. -Drew -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.323 / Virus Database: 267.6.6 - Release Date: 6/8/2005 -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.323 / Virus Database: 267.6.6 - Release Date: 6/8/2005