This memo is a status report on the parameters (i e., numbers and keywords) used in protocols in the Internet community. Distribution of this memo is unlimited

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Na základe vzťahov možno definovať pravdepodobnosť doručenia správy v čase . Ide zrejme o určenie maximálneho počtu retransmisií a následne o súčet pravdepodobností pre prípady žiadnej, jednej, dvoch až x retransmisií. Matematicky vyjadrené:

, kde

Po dosadení a úprave dostaneme:

Network Working Group J. Reynolds

Request for Comments: 1700 J. Postel


Obsoletes RFCs: 1340, 1060, 1010, 990, 960, October 1994

943, 923, 900, 870, 820, 790, 776, 770,

762, 758,755, 750, 739, 604, 503, 433, 349

Obsoletes IENs: 127, 117, 93

Category: Standards Track


Status of this Memo
This memo is a status report on the parameters (i.e., numbers and keywords) used in protocols in the Internet community. Distribution of this memo is unlimited.
This RFC is a snapshot of the ongoing process of the assignment of protocol parameters for the Internet protocol suite. To make the current information readily available the assignments are kept up-to- date in a set of online text files. This RFC has been assembled by catinating these files together with a minimum of formatting "glue". The authors appologize for the somewhat rougher formatting and style than is typical of most RFCs.
We expect that various readers will notice specific items that should be corrected. Please send any specific corrections via email to .

Reynolds & Postel [Page 1]

RFC 1700 Assigned Numbers October 1994


The files in this directory document the currently assigned values for

several series of numbers used in network protocol implementations.
The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols. The IANA is chartered by the Internet Society (ISOC) and the Federal Network Council (FNC) to act as the clearinghouse to assign and coordinate the use of numerous Internet protocol parameters.
The Internet protocol suite, as defined by the Internet Engineering Task Force (IETF) and its steering group (the IESG), contains numerous parameters, such as internet addresses, domain names, autonomous system numbers (used in some routing protocols), protocol numbers, port numbers, management information base object identifiers, including private enterprise numbers, and many others.
The common use of the Internet protocols by the Internet community requires that the particular values used in these parameter fields be assigned uniquely. It is the task of the IANA to make those unique assignments as requested and to maintain a registry of the currently assigned values.
Requests for parameter assignments (protocols, ports, etc.) should be

sent to .

Requests for SNMP network management private enterprise number assignments should be sent to .
The IANA is located at and operated by the Information Sciences

Institute (ISI) of the University of Southern California (USC).

If you are developing a protocol or application that will require the use of a link, socket, port, protocol, etc., please contact the IANA to receive a number assignment.
Joyce K. Reynolds

Internet Assigned Numbers Authority

USC - Information Sciences Institute

4676 Admiralty Way

Marina del Rey, California 90292-6695
Electronic mail: IANA@ISI.EDU

Phone: +1 310-822-1511

Reynolds & Postel [Page 2]

RFC 1700 Assigned Numbers October 1994

Most of the protocols are documented in the RFC series of notes. Some of the items listed are undocumented. Further information on protocols can be found in the memo, Internet Official Protocol Standards" (STD 1).
Data Notations
The convention in the documentation of Internet Protocols is to express numbers in decimal and to picture data in "big-endian" order [COHEN]. That is, fields are described left to right, with the most significant octet on the left and the least significant octet on the right.
The order of transmission of the header and data described in this document is resolved to the octet level. Whenever a diagram shows a group of octets, the order of transmission of those octets is the normal order in which they are read in English. For example, in the following diagram the octets are transmitted in the order they are numbered.

0 1 2 3

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1


| 1 | 2 | 3 | 4 |


| 5 | 6 | 7 | 8 |


| 9 | 10 | 11 | 12 |


Transmission Order of Bytes
Whenever an octet represents a numeric quantity the left most bit in the diagram is the high order or most significant bit. That is, the bit labeled 0 is the most significant bit. For example, the following diagram represents the value 170 (decimal).

0 1 2 3 4 5 6 7


|1 0 1 0 1 0 1 0|

Significance of Bits
Similarly, whenever a multi-octet field represents a numeric quantity

the left most bit of the whole field is the most significant bit. When

Reynolds & Postel [Page 3]

RFC 1700 Assigned Numbers October 1994

a multi-octet quantity is transmitted the most significant octet is

transmitted first.
Special Addresses
There are five classes of IP addresses: Class A through Class E. Of these, Classes A, B, and C are used for unicast addresses, Class D is used for multicast addresses, and Class E addresses are reserved for future use.
With the advent of classless addressing [CIDR1, CIDR2], the

network-number part of an address may be of any length, and the whole

notion of address classes becomes less important.
There are certain special cases for IP addresses. These special cases can be concisely summarized using the earlier notation for an IP address:
IP-address ::= { ,

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