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Title
Title:
Internet Hosts per 10000 People
SubTitle:
Subregional level
Filename:  
sreg_internet_hosts
 
 
 
General Description
Abstract:
The Internet Domain Survey has been taken twice a year since 1987. The original survey methodology counted hosts by walking the domain name tree and doing zone transfers of domain data in order to discover hosts and further subdomains. It is described more completely in RFC1296. The old survey counted the number of domain names that had IP addresses assigned to them. However, by July 1997 the Domain Survey was not able to count a significant portion of the hosts in the domain system, due to some organizations restricting download access to their domain data. The blocking of downloads (or zone transfers as they are called) had increased to the point where in the July 1997 survey we could only download 75% of the domains we discovered. We decided to try a new survey technique before the old one became useless. In January 1998, we ran the first "new" Internet Domain Survey. The new domain survey is the reverse of the old survey. It counts the number of IP addresses that have been assigned a name. This distinction is subtle but it does mean the new survey is counting a different "thing" than the old survey. Because of this, comparing data from the old and new surveys will not necessarily be a good thing to do in all cases. The new survey works by querying the domain system for the name assigned to every possible IP address. However, this would take too long if we had to send a query for each of the potential 4.3 billion (2^32) IP addresses that can exist. Instead, we start with a list of all network numbers that have been delegated within the IN-ADDR.ARPA domain. The IN-ADDR.ARPA domain is a special part of the domain name space used to convert IP addresses into names. For each IN-ADDR.ARPA network number delegation, we query for further subdelegations at each network octet boundary below that point. This process takes about two days and when it ends we have a list of all 3-octet network number delegations that exist and the names of the authoritative domain servers that handle those queries. This process reduces the number of queries we need to do from 4.3 billion to the number of possible hosts per delegation (254) times the number of delegations found. In the January 1998 survey, there were 879,212 delegations, or just 223,319,848 possible hosts. With the list of 3-octet delegations in hand, the next phase of the survey sends out a common UDP-based PTR query for each possible host address between 1 and 254 for each delegation. In order to prevent flooding any particular server, network or router with packets, the query order is pseudo-randomized to spread the queries evenly across the Internet. For example, a domain server that handles a single 3-octet IN-ADDR.ARPA delegation would only see one or two queries per hour. Depending on the time of day, we transmit between 600 and 1200 queries per second. The queries are streamed out asynchronously and we handle replies as they return. This phase takes about 8 days to run. More information: http://www.worldbank.org/data/ http://www.isc.org/ds/ http://www.isc.org/ds/new-survey.html
Purpose:
The Domain Survey attempts to discover every host on the Internet by doing a complete search of the Domain Name System. It is sponsored by the Internet Software Consortium with technical operations subcontracted to Network Wizards
Units:
Number of Computers
GEO Theme:
Socio-Economy
GEO Data Category:   
Infrastructure
Type:
Other Documents
Subtype:
-----
Language:
English
Status:
Complete
Maintenance:
Unknown
 
 
 
Keywords
GEMET Theme:
General (other)
Free Keywords:
Internet, hosts per 10000 people, subregional level
 
 
 
Online Reference
URL:
No reference for download
File Format:
-----
 
 
 
Spatial Reference
Coverage:
World
Coordinates:
 
North
90
 
West -180
 
180 East
 
-90
South
 
Region:
World
Subregion:
-----
Resolution:
Subregion
 
 
 
Temporal Reference
Covered Time:
1994-1999
 
 
 
Responsability
Person:
Jaap Van Woerden
Organization:
UNEP/DEWA/GRID-Geneva
Address:
11, chemin des Anemones
 
 
Postal Code:
1219
City:
Chatelaine
State:
Geneva
Country:
Switzerland
Phone:
+41 22 917 82 94
Fax:
+41 22 917 80 29
Email:
geo@grid.unep.ch
 
 
Publisher:
UNEP/GRID
Publ. Place:
Geneva
 
 
Publ. Year:
2002
Data Source:
ISC
Data Provider:
WB
Copyright:
UNEP/GRID
User Constr.:
Public
 
 
 
Metadata Information
Person:
Gregory Giuliani
Organization:
UNEP/DEWA/GRID-Geneva
Address:
11, Chemin des Anemones
 
 
Postal Code:
1219
City:
Chatelaine
State:
Geneva
Country:
Switzerland
Phone:
+41 22 917 82 94
Fax:
+41 22 917 80 29
Email:
geo@grid.unep.ch
 
 
Date:
20020320
 
 
 
 
 
GIS Data Info
Projection:
-----
 
 
Min. Scale:
-----
Max. Scale
-----
Data Resol.:
-----
Data Format:
-----
 
 
 
Statistics Data Info
Aggregation method
Mehtod:
Weighted average
Weight factor:
Total Population
Comments:
The data is only aggregated if at least 75 % of the observations are available (i.e. % of population or % of area or % of countries) on an annual basis. The value "-9999" corresponds to "No Data"
 
Interpolations/Extrapolations
Interpolations:
Aggregations only
Extrapolations:
None
Method:
Trend
Comments:
Some values are calculated by interpolations; they are exclusively used for the regional/subregional and global aggregations.
 
Calculated pre 1991-1992 relative country share
Former USSR:
None
Former Yugoslavia SFR:
None
Former Czechoslovakia:
None
Former Ethiopia:
None
Comments:
-----
 
General comments
Country notes:
Data for China do not include Hong Kong.
Definitions:
Internet hosts are computers connected directly to the worldwide network, each allowing many computer users to access the Internet. Hosts are assigned to countries on the basis of the hostís country code, though this does not necessarily indicate that the host is physically located in that country. All hosts lacking a country code identification are assigned to the United States. The Internet Software Consortium changed the methods used in its Internet domain survey beginning in July 1998. The new survey is believed to be more reliable and to avoid the undercounting that occurs when organizations restrict download access to their domain data. Nevertheless, some measurement problems remain, so the number of Internet hosts shown for each country should be considered an approximation. In particular, most hosts are now under generic top-level domains (for example, .com, .net, and .org), which, unlike country code top-level domains (.de, .uk), have never had a geographic designation. For detailed analysis of Internet trends by country, it is best to use the original source data.
Comments:
Copyright c 2002 (Aggregations) United Nations Environment Programme/DEWA/GRID-Geneva. Data aggregation made by Andrea DeBono and Ola Nordbeck (UNEP/DEWA/GRID-Geneva).