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Acceptable Use Policy

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Acceptable Use

© ESCOM Corp. 2000-2005


This page provides ESCOM Corporation's policy regarding use of our network hosts. We provide e-mail, name services (DNS), and web services.

Electronic Mail

E-mail is intended for the use of ESCOM's customers, potential customers, suppliers, employees, and acquaintances of our employees. We reject the idea that spammers have a First Amendment right to dump tons of junk onto our mail server. (Indeed, if you want to talk about the Bill of Rights, we believe we have a right to protect our own facilities, much like the Founders intended when they gave us the Second Amendment.)

ESCOM Corporation does not wish e-mail advertising from anyone or any business that we do not have an existing business relationship with. We do not consider mutual membership in a Chamber of Commerce to constitute "an existing business relationship." Examples of existing relationships include:

  • Business relationships. We have already bought something from you, or you have bought something from us.
  • Solicited information. We have inquired about one of your products or services.

No other advertising is permitted. If you send us e-mail advertising outside of these guidelines we will block your domain or IP address.

Even if you have some sort of a relationship with ESCOM, any subsequent e-mail must be within the context of that relationship. For example, if we inquired via e-mail about a software product, that doesn't permit your web hosting division to advertise to us about their web hosting services. And if you have a friend that works at ESCOM, that doesn't permit you to send all of our users an advertisement for your porn site.

Reasons We Block E-mail

ESCOM uses our ASMTP Appliance to automatically identify risky behavior (zombie clients, open relays, forged addresses, etc.) and either reject or quarantine mail from such sources.

  • Forged Addresses. ESCOM rejects mail with probably forged sender addresses. This includes addresses with nonexistent domains, addresses denied by SPF, and nonexistent addresses detected by our patented address verification technology.
  • Zombie Clients. ESCOM rejects mail from desktop clients (dialup, ADSL, cable modem, etc). Most of these are Microsoft zombies that have been hijacked and being used to redirect spam. If you want to send us e-mail, send it via your ISP's mail server.
  • Open Relay. ESCOM rejects mail from open SMTP relays.
  • DNS Problems. ASMTP quarantines messages from remote hosts with incomplete or inconsistent Domain Name System (DNS) information. Legitimate SMTP servers should have consistent DNS Pointer (PTR) and Address (A) records. For example, the PTR record for contains the name, and the Address record for includes the address If either record is missing or if the two records are inconsistent, ESCOM will block or quarantine your message.
  • Bulk Mailers. The Can-Spam Act of 2003 gives you the right to send everyone in the USA at least one advertisement (a friend calls it the "You Can Spam Act"). We're not so generous. If your servers send us spam, or we see your messages in our quarantine, we will block your domain and/or IP addresses for a few months. No warnings, no waivers. The only way off this list is to let the clock expire or to stop showing up in our logs.

If ESCOM.COM is blocking your mail and you have something to say to us, then print it out and send it to: ESCOM Corporation, Spam Department, PO Box 626, Oakton, VA 22124 USA. And put a stamp on it.


The only network services we make publicly available are e-mail (as described by our rules above), DNS name services (via UDP), and web services. Not very interesting, eh? Other services are restricted for the legitimate business use of ESCOM Corporation and its customers.

Attempts to Penetrate our Network Security

If you attempt to penetrate our network security, we will detect it and stop it. We will report it to the appropriate authorities, including the CERT. And then we will seek legal damages to the extent possible under the law.

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