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RFC1034_part5.txt
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RFC1034_part5.txt
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6. A SCENARIO
In our sample domain space, suppose we wanted separate administrative
control for the root, MIL, EDU, MIT.EDU and ISI.EDU zones. We might
allocate name servers as follows:
|(C.ISI.EDU,SRI-NIC.ARPA
| A.ISI.EDU)
+---------------------+------------------+
| | |
MIL EDU ARPA
|(SRI-NIC.ARPA, |(SRI-NIC.ARPA, |
| A.ISI.EDU | C.ISI.EDU) |
+-----+-----+ | +------+-----+-----+
| | | | | | |
BRL NOSC DARPA | IN-ADDR SRI-NIC ACC
|
+--------+------------------+---------------+--------+
| | | | |
UCI MIT | UDEL YALE
|(XX.LCS.MIT.EDU, ISI
|ACHILLES.MIT.EDU) |(VAXA.ISI.EDU,VENERA.ISI.EDU,
+---+---+ | A.ISI.EDU)
| | |
LCS ACHILLES +--+-----+-----+--------+
| | | | | |
XX A C VAXA VENERA Mockapetris
Mockapetris [Page 36]
RFC 1034 Domain Concepts and Facilities November 1987
In this example, the authoritative name server is shown in parentheses
at the point in the domain tree at which is assumes control.
Thus the root name servers are on C.ISI.EDU, SRI-NIC.ARPA, and
A.ISI.EDU. The MIL domain is served by SRI-NIC.ARPA and A.ISI.EDU. The
EDU domain is served by SRI-NIC.ARPA. and C.ISI.EDU. Note that servers
may have zones which are contiguous or disjoint. In this scenario,
C.ISI.EDU has contiguous zones at the root and EDU domains. A.ISI.EDU
has contiguous zones at the root and MIL domains, but also has a non-
contiguous zone at ISI.EDU.
6.1. C.ISI.EDU name server
C.ISI.EDU is a name server for the root, MIL, and EDU domains of the IN
class, and would have zones for these domains. The zone data for the
root domain might be:
. IN SOA SRI-NIC.ARPA. HOSTMASTER.SRI-NIC.ARPA. (
870611 ;serial
1800 ;refresh every 30 min
300 ;retry every 5 min
604800 ;expire after a week
86400) ;minimum of a day
NS A.ISI.EDU.
NS C.ISI.EDU.
NS SRI-NIC.ARPA.
MIL. 86400 NS SRI-NIC.ARPA.
86400 NS A.ISI.EDU.
EDU. 86400 NS SRI-NIC.ARPA.
86400 NS C.ISI.EDU.
SRI-NIC.ARPA. A 26.0.0.73
A 10.0.0.51
MX 0 SRI-NIC.ARPA.
HINFO DEC-2060 TOPS20
ACC.ARPA. A 26.6.0.65
HINFO PDP-11/70 UNIX
MX 10 ACC.ARPA.
USC-ISIC.ARPA. CNAME C.ISI.EDU.
73.0.0.26.IN-ADDR.ARPA. PTR SRI-NIC.ARPA.
65.0.6.26.IN-ADDR.ARPA. PTR ACC.ARPA.
51.0.0.10.IN-ADDR.ARPA. PTR SRI-NIC.ARPA.
52.0.0.10.IN-ADDR.ARPA. PTR C.ISI.EDU.
Mockapetris [Page 37]
RFC 1034 Domain Concepts and Facilities November 1987
103.0.3.26.IN-ADDR.ARPA. PTR A.ISI.EDU.
A.ISI.EDU. 86400 A 26.3.0.103
C.ISI.EDU. 86400 A 10.0.0.52
This data is represented as it would be in a master file. Most RRs are
single line entries; the sole exception here is the SOA RR, which uses
"(" to start a multi-line RR and ")" to show the end of a multi-line RR.
Since the class of all RRs in a zone must be the same, only the first RR
in a zone need specify the class. When a name server loads a zone, it
forces the TTL of all authoritative RRs to be at least the MINIMUM field
of the SOA, here 86400 seconds, or one day. The NS RRs marking
delegation of the MIL and EDU domains, together with the glue RRs for
the servers host addresses, are not part of the authoritative data in
the zone, and hence have explicit TTLs.
Four RRs are attached to the root node: the SOA which describes the root
zone and the 3 NS RRs which list the name servers for the root. The
data in the SOA RR describes the management of the zone. The zone data
is maintained on host SRI-NIC.ARPA, and the responsible party for the
zone is [email protected]. A key item in the SOA is the 86400
second minimum TTL, which means that all authoritative data in the zone
has at least that TTL, although higher values may be explicitly
specified.
The NS RRs for the MIL and EDU domains mark the boundary between the
root zone and the MIL and EDU zones. Note that in this example, the
lower zones happen to be supported by name servers which also support
the root zone.
The master file for the EDU zone might be stated relative to the origin
EDU. The zone data for the EDU domain might be:
EDU. IN SOA SRI-NIC.ARPA. HOSTMASTER.SRI-NIC.ARPA. (
870729 ;serial
1800 ;refresh every 30 minutes
300 ;retry every 5 minutes
604800 ;expire after a week
86400 ;minimum of a day
)
NS SRI-NIC.ARPA.
NS C.ISI.EDU.
UCI 172800 NS ICS.UCI
172800 NS ROME.UCI
ICS.UCI 172800 A 192.5.19.1
ROME.UCI 172800 A 192.5.19.31
Mockapetris [Page 38]
RFC 1034 Domain Concepts and Facilities November 1987
ISI 172800 NS VAXA.ISI
172800 NS A.ISI
172800 NS VENERA.ISI.EDU.
VAXA.ISI 172800 A 10.2.0.27
172800 A 128.9.0.33
VENERA.ISI.EDU. 172800 A 10.1.0.52
172800 A 128.9.0.32
A.ISI 172800 A 26.3.0.103
UDEL.EDU. 172800 NS LOUIE.UDEL.EDU.
172800 NS UMN-REI-UC.ARPA.
LOUIE.UDEL.EDU. 172800 A 10.0.0.96
172800 A 192.5.39.3
YALE.EDU. 172800 NS YALE.ARPA.
YALE.EDU. 172800 NS YALE-BULLDOG.ARPA.
MIT.EDU. 43200 NS XX.LCS.MIT.EDU.
43200 NS ACHILLES.MIT.EDU.
XX.LCS.MIT.EDU. 43200 A 10.0.0.44
ACHILLES.MIT.EDU. 43200 A 18.72.0.8
Note the use of relative names here. The owner name for the ISI.EDU. is
stated using a relative name, as are two of the name server RR contents.
Relative and absolute domain names may be freely intermixed in a master
6.2. Example standard queries
The following queries and responses illustrate name server behavior.
Unless otherwise noted, the queries do not have recursion desired (RD)
in the header. Note that the answers to non-recursive queries do depend
on the server being asked, but do not depend on the identity of the
requester.
Mockapetris [Page 39]
RFC 1034 Domain Concepts and Facilities November 1987
6.2.1. QNAME=SRI-NIC.ARPA, QTYPE=A
The query would look like:
+---------------------------------------------------+
Header | OPCODE=SQUERY |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
The response from C.ISI.EDU would be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 86400 IN A 26.0.0.73 |
| 86400 IN A 10.0.0.51 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
The header of the response looks like the header of the query, except
that the RESPONSE bit is set, indicating that this message is a
response, not a query, and the Authoritative Answer (AA) bit is set
indicating that the address RRs in the answer section are from
authoritative data. The question section of the response matches the
question section of the query.
Mockapetris [Page 40]
RFC 1034 Domain Concepts and Facilities November 1987
If the same query was sent to some other server which was not
authoritative for SRI-NIC.ARPA, the response might be:
+---------------------------------------------------+
Header | OPCODE=SQUERY,RESPONSE |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 1777 IN A 10.0.0.51 |
| 1777 IN A 26.0.0.73 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
This response is different from the previous one in two ways: the header
does not have AA set, and the TTLs are different. The inference is that
the data did not come from a zone, but from a cache. The difference
between the authoritative TTL and the TTL here is due to aging of the
data in a cache. The difference in ordering of the RRs in the answer
section is not significant.
6.2.2. QNAME=SRI-NIC.ARPA, QTYPE=*
A query similar to the previous one, but using a QTYPE of *, would
receive the following response from C.ISI.EDU:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=* |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 86400 IN A 26.0.0.73 |
| A 10.0.0.51 |
| MX 0 SRI-NIC.ARPA. |
| HINFO DEC-2060 TOPS20 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
Mockapetris [Page 41]
RFC 1034 Domain Concepts and Facilities November 1987
If a similar query was directed to two name servers which are not
authoritative for SRI-NIC.ARPA, the responses might be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=* |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 12345 IN A 26.0.0.73 |
| A 10.0.0.51 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
and
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=* |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 1290 IN HINFO DEC-2060 TOPS20 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
Neither of these answers have AA set, so neither response comes from
authoritative data. The different contents and different TTLs suggest
that the two servers cached data at different times, and that the first
server cached the response to a QTYPE=A query and the second cached the
response to a HINFO query.
Mockapetris [Page 42]
RFC 1034 Domain Concepts and Facilities November 1987
6.2.3. QNAME=SRI-NIC.ARPA, QTYPE=MX
This type of query might be result from a mailer trying to look up
routing information for the mail destination [email protected].
The response from C.ISI.EDU would be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=MX |
+---------------------------------------------------+
Answer | SRI-NIC.ARPA. 86400 IN MX 0 SRI-NIC.ARPA.|
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | SRI-NIC.ARPA. 86400 IN A 26.0.0.73 |
| A 10.0.0.51 |
+---------------------------------------------------+
This response contains the MX RR in the answer section of the response.
The additional section contains the address RRs because the name server
at C.ISI.EDU guesses that the requester will need the addresses in order
to properly use the information carried by the MX.
6.2.4. QNAME=SRI-NIC.ARPA, QTYPE=NS
C.ISI.EDU would reply to this query with:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=SRI-NIC.ARPA., QCLASS=IN, QTYPE=NS |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
The only difference between the response and the query is the AA and
RESPONSE bits in the header. The interpretation of this response is
that the server is authoritative for the name, and the name exists, but
no RRs of type NS are present there.
6.2.5. QNAME=SIR-NIC.ARPA, QTYPE=A
If a user mistyped a host name, we might see this type of query.
Mockapetris [Page 43]
RFC 1034 Domain Concepts and Facilities November 1987
C.ISI.EDU would answer it with:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA, RCODE=NE |
+---------------------------------------------------+
Question | QNAME=SIR-NIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | . SOA SRI-NIC.ARPA. HOSTMASTER.SRI-NIC.ARPA. |
| 870611 1800 300 604800 86400 |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
This response states that the name does not exist. This condition is
signalled in the response code (RCODE) section of the header.
The SOA RR in the authority section is the optional negative caching
information which allows the resolver using this response to assume that
the name will not exist for the SOA MINIMUM (86400) seconds.
6.2.6. QNAME=BRL.MIL, QTYPE=A
If this query is sent to C.ISI.EDU, the reply would be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE |
+---------------------------------------------------+
Question | QNAME=BRL.MIL, QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | MIL. 86400 IN NS SRI-NIC.ARPA. |
| 86400 NS A.ISI.EDU. |
+---------------------------------------------------+
Additional | A.ISI.EDU. A 26.3.0.103 |
| SRI-NIC.ARPA. A 26.0.0.73 |
| A 10.0.0.51 |
+---------------------------------------------------+
This response has an empty answer section, but is not authoritative, so
it is a referral. The name server on C.ISI.EDU, realizing that it is
not authoritative for the MIL domain, has referred the requester to
servers on A.ISI.EDU and SRI-NIC.ARPA, which it knows are authoritative
for the MIL domain.
Mockapetris [Page 44]
RFC 1034 Domain Concepts and Facilities November 1987
6.2.7. QNAME=USC-ISIC.ARPA, QTYPE=A
The response to this query from A.ISI.EDU would be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=USC-ISIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | USC-ISIC.ARPA. 86400 IN CNAME C.ISI.EDU. |
| C.ISI.EDU. 86400 IN A 10.0.0.52 |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
Note that the AA bit in the header guarantees that the data matching
QNAME is authoritative, but does not say anything about whether the data
for C.ISI.EDU is authoritative. This complete reply is possible because
A.ISI.EDU happens to be authoritative for both the ARPA domain where
USC-ISIC.ARPA is found and the ISI.EDU domain where C.ISI.EDU data is
found.
If the same query was sent to C.ISI.EDU, its response might be the same
as shown above if it had its own address in its cache, but might also
be:
Mockapetris [Page 45]
RFC 1034 Domain Concepts and Facilities November 1987
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=USC-ISIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | USC-ISIC.ARPA. 86400 IN CNAME C.ISI.EDU. |
+---------------------------------------------------+
Authority | ISI.EDU. 172800 IN NS VAXA.ISI.EDU. |
| NS A.ISI.EDU. |
| NS VENERA.ISI.EDU. |
+---------------------------------------------------+
Additional | VAXA.ISI.EDU. 172800 A 10.2.0.27 |
| 172800 A 128.9.0.33 |
| VENERA.ISI.EDU. 172800 A 10.1.0.52 |
| 172800 A 128.9.0.32 |
| A.ISI.EDU. 172800 A 26.3.0.103 |
+---------------------------------------------------+
This reply contains an authoritative reply for the alias USC-ISIC.ARPA,
plus a referral to the name servers for ISI.EDU. This sort of reply
isn't very likely given that the query is for the host name of the name
server being asked, but would be common for other aliases.
6.2.8. QNAME=USC-ISIC.ARPA, QTYPE=CNAME
If this query is sent to either A.ISI.EDU or C.ISI.EDU, the reply would
be:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=USC-ISIC.ARPA., QCLASS=IN, QTYPE=A |
+---------------------------------------------------+
Answer | USC-ISIC.ARPA. 86400 IN CNAME C.ISI.EDU. |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
Because QTYPE=CNAME, the CNAME RR itself answers the query, and the name
server doesn't attempt to look up anything for C.ISI.EDU. (Except
possibly for the additional section.)
6.3. Example resolution
The following examples illustrate the operations a resolver must perform
for its client. We assume that the resolver is starting without a
Mockapetris [Page 46]
RFC 1034 Domain Concepts and Facilities November 1987
cache, as might be the case after system boot. We further assume that
the system is not one of the hosts in the data and that the host is
located somewhere on net 26, and that its safety belt (SBELT) data
structure has the following information:
Match count = -1
SRI-NIC.ARPA. 26.0.0.73 10.0.0.51
A.ISI.EDU. 26.3.0.103
This information specifies servers to try, their addresses, and a match
count of -1, which says that the servers aren't very close to the
target. Note that the -1 isn't supposed to be an accurate closeness
measure, just a value so that later stages of the algorithm will work.
The following examples illustrate the use of a cache, so each example
assumes that previous requests have completed.
6.3.1. Resolve MX for ISI.EDU.
Suppose the first request to the resolver comes from the local mailer,
which has mail for [email protected]. The mailer might then ask for type MX
RRs for the domain name ISI.EDU.
The resolver would look in its cache for MX RRs at ISI.EDU, but the
empty cache wouldn't be helpful. The resolver would recognize that it
needed to query foreign servers and try to determine the best servers to
query. This search would look for NS RRs for the domains ISI.EDU, EDU,
and the root. These searches of the cache would also fail. As a last
resort, the resolver would use the information from the SBELT, copying
it into its SLIST structure.
At this point the resolver would need to pick one of the three available
addresses to try. Given that the resolver is on net 26, it should
choose either 26.0.0.73 or 26.3.0.103 as its first choice. It would
then send off a query of the form:
Mockapetris [Page 47]
RFC 1034 Domain Concepts and Facilities November 1987
+---------------------------------------------------+
Header | OPCODE=SQUERY |
+---------------------------------------------------+
Question | QNAME=ISI.EDU., QCLASS=IN, QTYPE=MX |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
The resolver would then wait for a response to its query or a timeout.
If the timeout occurs, it would try different servers, then different
addresses of the same servers, lastly retrying addresses already tried.
It might eventually receive a reply from SRI-NIC.ARPA:
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE |
+---------------------------------------------------+
Question | QNAME=ISI.EDU., QCLASS=IN, QTYPE=MX |
+---------------------------------------------------+
Answer | <empty> |
+---------------------------------------------------+
Authority | ISI.EDU. 172800 IN NS VAXA.ISI.EDU. |
| NS A.ISI.EDU. |
| NS VENERA.ISI.EDU.|
+---------------------------------------------------+
Additional | VAXA.ISI.EDU. 172800 A 10.2.0.27 |
| 172800 A 128.9.0.33 |
| VENERA.ISI.EDU. 172800 A 10.1.0.52 |
| 172800 A 128.9.0.32 |
| A.ISI.EDU. 172800 A 26.3.0.103 |
+---------------------------------------------------+
The resolver would notice that the information in the response gave a
closer delegation to ISI.EDU than its existing SLIST (since it matches
three labels). The resolver would then cache the information in this
response and use it to set up a new SLIST:
Match count = 3
A.ISI.EDU. 26.3.0.103
VAXA.ISI.EDU. 10.2.0.27 128.9.0.33
VENERA.ISI.EDU. 10.1.0.52 128.9.0.32
A.ISI.EDU appears on this list as well as the previous one, but that is
purely coincidental. The resolver would again start transmitting and
waiting for responses. Eventually it would get an answer:
Mockapetris [Page 48]
RFC 1034 Domain Concepts and Facilities November 1987
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=ISI.EDU., QCLASS=IN, QTYPE=MX |
+---------------------------------------------------+
Answer | ISI.EDU. MX 10 VENERA.ISI.EDU. |
| MX 20 VAXA.ISI.EDU. |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | VAXA.ISI.EDU. 172800 A 10.2.0.27 |
| 172800 A 128.9.0.33 |
| VENERA.ISI.EDU. 172800 A 10.1.0.52 |
| 172800 A 128.9.0.32 |
+---------------------------------------------------+
The resolver would add this information to its cache, and return the MX
RRs to its client.
6.3.2. Get the host name for address 26.6.0.65
The resolver would translate this into a request for PTR RRs for
65.0.6.26.IN-ADDR.ARPA. This information is not in the cache, so the
resolver would look for foreign servers to ask. No servers would match,
so it would use SBELT again. (Note that the servers for the ISI.EDU
domain are in the cache, but ISI.EDU is not an ancestor of
65.0.6.26.IN-ADDR.ARPA, so the SBELT is used.)
Since this request is within the authoritative data of both servers in
SBELT, eventually one would return:
Mockapetris [Page 49]
RFC 1034 Domain Concepts and Facilities November 1987
+---------------------------------------------------+
Header | OPCODE=SQUERY, RESPONSE, AA |
+---------------------------------------------------+
Question | QNAME=65.0.6.26.IN-ADDR.ARPA.,QCLASS=IN,QTYPE=PTR |
+---------------------------------------------------+
Answer | 65.0.6.26.IN-ADDR.ARPA. PTR ACC.ARPA. |
+---------------------------------------------------+
Authority | <empty> |
+---------------------------------------------------+
Additional | <empty> |
+---------------------------------------------------+
6.3.3. Get the host address of poneria.ISI.EDU
This request would translate into a type A request for poneria.ISI.EDU.
The resolver would not find any cached data for this name, but would
find the NS RRs in the cache for ISI.EDU when it looks for foreign
servers to ask. Using this data, it would construct a SLIST of the
form:
Match count = 3
A.ISI.EDU. 26.3.0.103
VAXA.ISI.EDU. 10.2.0.27 128.9.0.33
VENERA.ISI.EDU. 10.1.0.52
A.ISI.EDU is listed first on the assumption that the resolver orders its
choices by preference, and A.ISI.EDU is on the same network.
One of these servers would answer the query.
7. REFERENCES and BIBLIOGRAPHY
[Dyer 87] Dyer, S., and F. Hsu, "Hesiod", Project Athena
Technical Plan - Name Service, April 1987, version 1.9.
Describes the fundamentals of the Hesiod name service.
[IEN-116] J. Postel, "Internet Name Server", IEN-116,
USC/Information Sciences Institute, August 1979.
A name service obsoleted by the Domain Name System, but
still in use.
Mockapetris [Page 50]
RFC 1034 Domain Concepts and Facilities November 1987
[Quarterman 86] Quarterman, J., and J. Hoskins, "Notable Computer
Networks",Communications of the ACM, October 1986,
volume 29, number 10.
[RFC-742] K. Harrenstien, "NAME/FINGER", RFC-742, Network
Information Center, SRI International, December 1977.
[RFC-768] J. Postel, "User Datagram Protocol", RFC-768,
USC/Information Sciences Institute, August 1980.
[RFC-793] J. Postel, "Transmission Control Protocol", RFC-793,
USC/Information Sciences Institute, September 1981.
[RFC-799] D. Mills, "Internet Name Domains", RFC-799, COMSAT,
September 1981.
Suggests introduction of a hierarchy in place of a flat
name space for the Internet.
[RFC-805] J. Postel, "Computer Mail Meeting Notes", RFC-805,
USC/Information Sciences Institute, February 1982.
[RFC-810] E. Feinler, K. Harrenstien, Z. Su, and V. White, "DOD
Internet Host Table Specification", RFC-810, Network
Information Center, SRI International, March 1982.
Obsolete. See RFC-952.
[RFC-811] K. Harrenstien, V. White, and E. Feinler, "Hostnames
Server", RFC-811, Network Information Center, SRI
International, March 1982.
Obsolete. See RFC-953.
[RFC-812] K. Harrenstien, and V. White, "NICNAME/WHOIS", RFC-812,
Network Information Center, SRI International, March
1982.
[RFC-819] Z. Su, and J. Postel, "The Domain Naming Convention for
Internet User Applications", RFC-819, Network
Information Center, SRI International, August 1982.
Early thoughts on the design of the domain system.
Current implementation is completely different.
[RFC-821] J. Postel, "Simple Mail Transfer Protocol", RFC-821,
USC/Information Sciences Institute, August 1980.
Mockapetris [Page 51]
RFC 1034 Domain Concepts and Facilities November 1987
[RFC-830] Z. Su, "A Distributed System for Internet Name Service",
RFC-830, Network Information Center, SRI International,
October 1982.
Early thoughts on the design of the domain system.
Current implementation is completely different.
[RFC-882] P. Mockapetris, "Domain names - Concepts and
Facilities," RFC-882, USC/Information Sciences
Institute, November 1983.
Superceeded by this memo.
[RFC-883] P. Mockapetris, "Domain names - Implementation and
Specification," RFC-883, USC/Information Sciences
Institute, November 1983.
Superceeded by this memo.
[RFC-920] J. Postel and J. Reynolds, "Domain Requirements",
RFC-920, USC/Information Sciences Institute
October 1984.
Explains the naming scheme for top level domains.
[RFC-952] K. Harrenstien, M. Stahl, E. Feinler, "DoD Internet Host
Table Specification", RFC-952, SRI, October 1985.
Specifies the format of HOSTS.TXT, the host/address
table replaced by the DNS.
[RFC-953] K. Harrenstien, M. Stahl, E. Feinler, "HOSTNAME Server",
RFC-953, SRI, October 1985.
This RFC contains the official specification of the
hostname server protocol, which is obsoleted by the DNS.
This TCP based protocol accesses information stored in
the RFC-952 format, and is used to obtain copies of the
host table.
[RFC-973] P. Mockapetris, "Domain System Changes and
Observations", RFC-973, USC/Information Sciences
Institute, January 1986.
Describes changes to RFC-882 and RFC-883 and reasons for
them. Now obsolete.
Mockapetris [Page 52]
RFC 1034 Domain Concepts and Facilities November 1987
[RFC-974] C. Partridge, "Mail routing and the domain system",
RFC-974, CSNET CIC BBN Labs, January 1986.
Describes the transition from HOSTS.TXT based mail
addressing to the more powerful MX system used with the
domain system.
[RFC-1001] NetBIOS Working Group, "Protocol standard for a NetBIOS
service on a TCP/UDP transport: Concepts and Methods",
RFC-1001, March 1987.
This RFC and RFC-1002 are a preliminary design for
NETBIOS on top of TCP/IP which proposes to base NetBIOS
name service on top of the DNS.
[RFC-1002] NetBIOS Working Group, "Protocol standard for a NetBIOS
service on a TCP/UDP transport: Detailed
Specifications", RFC-1002, March 1987.
[RFC-1010] J. Reynolds and J. Postel, "Assigned Numbers", RFC-1010,
USC/Information Sciences Institute, May 1987
Contains socket numbers and mnemonics for host names,
operating systems, etc.
[RFC-1031] W. Lazear, "MILNET Name Domain Transition", RFC-1031,
November 1987.
Describes a plan for converting the MILNET to the DNS.
[RFC-1032] M. K. Stahl, "Establishing a Domain - Guidelines for
Administrators", RFC-1032, November 1987.
Describes the registration policies used by the NIC to
administer the top level domains and delegate subzones.
[RFC-1033] M. K. Lottor, "Domain Administrators Operations Guide",
RFC-1033, November 1987.
A cookbook for domain administrators.
[Solomon 82] M. Solomon, L. Landweber, and D. Neuhengen, "The CSNET
Name Server", Computer Networks, vol 6, nr 3, July 1982.
Describes a name service for CSNET which is independent
from the DNS and DNS use in the CSNET.