Brno University of Technology

Brno, 31st December, 2001

To: Deans of Faculties, Bursar, Heads of BUT Parts

Drawn up by: Ing. Vladimír Záhořík, Ing. Petr Lampa


Article 1
General Provisions

  1. E-mail is used for exchanging short messages and documents in electronic format.
  2. The BUT network users have access to e-mail services subject to conditions stipulated by Rector's Directive no. 3/1999 - BUT Computer Network Operation Rules and no. 16/2001 BUT Computer Network Administration Rules. These E-Mail Rules define the technical conditions in which this service is provided.
  3. The person responsible for the operation of e-mail is an administrator appointed by the BUT Computer Network Administration Rules. For communication on e-mail administration, he/she uses e-mail address where is the name of the domain administered.
  4. E-mail is transferred using exclusively the Simple Mail Transfer Protocol (SMTP). For access to e-mail, the POP3 or IMAP4 protocols are recommended. Their specification can be found in the RFC documents at
  5. All e-mail must be transported exclusively through the official BUT Computer Network mail servers. The transport of e-mail through servers other than the official ones may be barred. A list of the BUT official mail servers is permanently published at
  6. Users must dispatch their e-mail so that it is routed through the official transport server assigned to the local or faculty computer network. E-mail messages sent through other servers may be locked out.
  7. E-mail is a service that requires a user to be identified under Article 2, Paragraph 4 of the BUT Computer Network Operation Rules. The person responsible for assigning names and access rights to this service is the relevant administrator. No anonymous access to e-mail services shall be admitted. Sending e-mail messages under assumed identity is seen as a serious breach of the BUT Computer Network Operation Rules.
  8. The software requirements of the e-mail service operation are listed below. Programs that do no meet these requirements may only be used in special cases (testing, emergency use, etc.)

Article 2
E-Mail Address Format

  1. For e-mail services, BUT uses the level 2 domain with IP addresses ranging from to (class B address). Within the BUT network, the BUT parts (faculties, university departments, student organisations, etc.) use level 3 domains with the format. They are listed at
  2. New level 2 and level 3 domains may only be established for legitimate purposes (a new faculty or a new university department established. etc.). They shall be assigned by the Computer and Information Services Centre (CISC) at
  3. By Rector's Directive no. 13/2001 (Institutional E-Mail Addresses of BUT Officials), official e-mail addresses are established for the BUT officials holding some offices.
  4. The Annex, which forms an integral part of this Directive, lists the addresses assigned to the computer network services administration (e-mail, DNS, Web, etc.). These addresses must exist and shall be used to communicate with the administrators of relevant network services.
  5. Every BUT user is assigned an e-mail address. Using a different e-mail address of the sender of an e-mail message is seen as a breach of the BUT Computer Network Operation Rules and such a message may not be delivered. The relevant administrator is responsible for assigning the addresses.

Article 3
E-Mail Format

  1. E-mail services must enable the transport of messages written in Czech and/or in English along with file attachments of a limited size exchanged between a sender and a recipient within the BUT network.
  2. The character set used for e-mail must comply with the current ISO standards (ISO-8859-1 for Western European languages and ISO-8859-2 for Central European languages, etc.)
  3. For communication with entities outside BUT, limitations, if any, of the other party must be respected (maximum message size, language limitations, etc.)
  4. Short messages should be sent as plain text without attachments.
  5. Attachments to an e-mail message should be coded using the MIME format (see RFC2045). Sending attachments in a different coding such as UUENCODE is not recommended. The names of attached files should only contain letters a-z, digits 0-9, the underscore (_ ), period (.), and the minus sign (-).
  6. The maximum size of a message including the encoded attachments guaranteed to be transported within BUT is 2 MB. The size of the mail-list and conference messages may be required less, but larger than 64 KB. For the transfer of larger files other services should be used such as Web, FTP, etc.
  7. The maximum size of a message sent to or received from student addresses may be required less, but larger than 64 KB.

Article 4
E-Mail Access

  1. For e-mail access on BUT official servers, the IMAP4, SSH (mutt, pine), and Web/https protocols are preferred.
  2. The relevant administrator shall determine the e-mail access mode (IMAP4/POP3, Web, terminal access, etc.) and inform the users accordingly.
  3. For e-mail received from and sent to addresses outside the BUT network, the sender's identity authorisation is recommended (AUTH extension).

Article 5
Administration of E-Mail Servers

  1. The Official BUT e-mail servers must conform to the following rules:
    1. they must be protected from e-mail transfer to a third party,
    2. they must enable the disablement of receipt from and transport to listedaddresses (domains),
    3. they must keep a log of received and transported messages for six months,
    4. its time must be synchronised with that of the BUT network,
    5. if user e-mail boxes are also stored on the same server, the user data must be backed up on a regular basis.
  2. Apart from obvious reasons such as the non-existence of a recipient's address, an e-mail server may refuse to accept an e-mail message if:
    1. it contains viruses or other harmful data whose transport does not comply with the BUT safety policy,
    2. it contains an address listed as barred for spawning unsolicited messages such as spam,
    3. it comes from a computer that is not correctly registered in DNS,
    4. it exceeds the required size,
    5. the recipient has exceeded the size limit set for his/her mail box.
  3. If an e-mail message is refused, its sender must be notified accordingly.
  4. The log of received, sent and transported messages must include at least the following data:
    1. date and time,
    2. address of the computer to/from which the message has been sent,
    3. sender's and recipient's address,
    4. message ID,
    5. message size,
    6. transaction result.

This Directive comes into force on the date it is signed and overrides Rector's Directive no. 62/1992.

Prof. RNDr. Ing. Jan Vrbka, DrSc.

URL addresses for network and services administration

Adress Established for Function all e-mail domains e-mail administration all authority zones (as found in SOA) DNS administration all Web servers Web server administration subdomains in outgoing NetNews addresses NetNews administration IRC server domains IRC administration domains of faculties and university parts security incidents domains of faculties and university parts e-mail abuse domains of faculties and university parts network failures domain network administrator conferences