IPPM Metrics for Measuring Connectivity (RFC2678)
Original Publication Date: 1999-Sep-01
Included in the Prior Art Database: 2019-Feb-11
Internet Society Requests For Comment (RFCs)
J. Mahdavi: AUTHOR [+1]
This memo defines a series of metrics for connectivity between a pair of Internet hosts. [STANDARDS-TRACK]
Network Working Group J. Mahdavi Request for Comments: 2678 Pittsburgh Supercomputing Center Obsoletes: 2498 V. Paxson Category: Standards Track Lawrence Berkeley National Laboratory September 1999
IPPM Metrics for Measuring Connectivity
Status of this Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1999). All Rights Reserved.
Connectivity is the basic stuff from which the Internet is made. Therefore, metrics determining whether pairs of hosts (IP addresses) can reach each other must form the base of a measurement suite. We define several such metrics, some of which serve mainly as building blocks for the others.
This memo defines a series of metrics for connectivity between a pair of Internet hosts. It builds on notions introduced and discussed in RFC 2330, the IPPM framework document. The reader is assumed to be familiar with that document.
The structure of the memo is as follows:
+ An analytic metric, called Type-P-Instantaneous-Unidirectional- Connectivity, will be introduced to define one-way connectivity at one moment in time. + Using this metric, another analytic metric, called Type-P- Instantaneous-Bidirectional-Connectivity, will be introduced to define two-way connectivity at one moment in time. + Using these metrics, corresponding one- and two-way analytic metrics are defined for connectivity over an interval of time.
Mahdavi & Paxson Standards Track [Page 1]
RFC 2678 IPPM Metrics for Measuring Connectivity September 1999
+ Using these metrics, an analytic metric, called Type-P1-P2- Interval-Temporal-Connectivity, will be introduced to define a useful notion of two-way connectivity between two hosts over an interval of time. + Methodologies are then presented and discussed for estimating Type-P1-P2-Interval-Temporal-Connectivity in a variety of settings.
Careful definition of Type-P1-P2-Interval-Temporal-Connectivity and the discussion of the metric and the methodologies for estimating it are the two chief contributions of the memo.
2. Instantaneous One-way Connectivity
2.1. Metric Name:
2.2. Metric Parameters:
+ Src, the IP address of a host + Dst, the IP address of a host + T, a time
2.3. Metric Units:
Src has *Type-P-Instantaneous-Unidirectional-Connectivity* to Dst at time T if a type-P packet transmitted from Src to Dst at time T will arrive at Dst.
For most applications (e.g., any TCP connection) bidirectional connectivity is considerably more germane than unidirectional connectivity, although unidirectional connectivity can be of interest for some security applications (e.g., tes...