Help:Range blocks/de


 * Siehe für Informationen zu IPv6-Bereichssperren.

Bereichssperren sind technische Einschränkungen, die durch Special:Block an einer Gruppe von IP-Adressen vorgenommen werden, um diese an Bearbeitungen, Accounterstellungen, E-Mail-Versand oder anderen Aktionen zu hindern. Die Option "" verhindert, dass die Sperre durch eingeloggte Benutzer umgangen werden kann.

Um einen IP-Bereich von Special:Block aus zu sperren, gib die erste IP-Adresse im Bereich ein, gefolgt von einem Schrägstrich und einem Classless inter-domain routing-Suffix (CIDR). Du solltest es vermeiden, Bereichssperren durchzuführen, es sei denn, du verstehst, was du tust, ansonsten könnten am Ende Zehntausende oder sogar Millionen von Menschen blockiert sein, die nicht das Problem sind!

Dieser Artikel behandelt hauptsächlich IPv4; IPv6-Blöcke funktionieren ähnlich, haben aber unterschiedliche Auswirkungen – siehe /IPv6.



Nicht-technische Erklärung
IP-Adressen werden in verschiedene Blöcke von Nummern aufgeteilt. Ein Beispiel hierfür wäre  bis. Sobald  erreicht, ist die nächste Zahl.

IP-Adressen können in kleinere oder größere Blöcke aufgeteilt werden. Der kleinste praktischer Block ist ein 4er-Block. Dies könnte eines der Folgenden sein:



Of each block of 4 numbers, only two can be assigned to a computer. The first and last numbers of any block are reserved for network communication. These are level 30 blocks and can be expressed like this:



Der nächstgrößerer Block ist 8. Die können wie folgend sein:



In this block of 8 numbers only 6 can be assigned to a computer as, once again, the first and last numbers in a block are reserved for specific uses in network communication. These can also be expressed as follows:



From this point on, the number of IP addresses in a block continues to double: 16, 32, 64, 128, 256, etc.


 * Ein Block von 16 würde bei  beginnen.
 * Ein Block von 32 würde bei  beginnen.
 * Ein Block von 64 würde bei  beginnen.
 * Ein Block von 128 würde bei  beginnen.
 * Ein Block von 256 würde bei  beginnen.

So if you have an IP address and you want to block the range assigned how do you know which one to use? Let's say you have a problem with. You can look up who has this IP address at http://arin.net/whois/?queryinput=148.20.57.34. Say this tells us that this IP address is assigned, along with a LOT of others in a  range, to the Department of Defense. We certainly don't want to block a large block of the DoD! The rule of thumb is block as little as possible. Only block a range if there is a cluster of IP addresses giving a problem.

There's a calculator that is very useful for this:


 * ftools/general/ip-range-calc.html

Go to this site and enter  into the first set of blanks. Now select Network Prefix Length and enter  (this will give a block of 32 addresses) and click Calculate Network Information. This will show us a block of 32 IP addresses that include. (The first - network - and the last - broadcast - addresses will be displayed along with the usable addresses in the range.) You can use this tool to test ranges to be sure they are what you want before entering the information to initiate the block.



Technische Erklärung
CIDR notation is written as the IP address, a slash, and the CIDR suffix (for example, the IPv4 " " or IPv6 " "). The CIDR suffix is the number of starting digits every IP address in the range have in common when written in binary.

For example: " " is binary " ", so  will match the first 27 digits (" "). The IP addresses –, when converted to binary, all have the same 27 first digits and will be blocked if   is blocked.

As the CIDR suffix increases, the block affects fewer IP addresses (see table of sample ranges). CIDR suffixes are not the same for IPv4 addresses as they are for IPv6 addresses; the same CIDR suffix in IPv4 blocks $$2^{96}$$=79,228,162,514,264,337,593,543,950,336 times as many addresses in IPv6.

Calculating the CIDR suffix
You can use the table of sample ranges below to guess the range, use a computer script, or manually calculate the range.



Umwandlung in Binär
The first step in manually calculating a range is to convert the first and last IP address to binary representation. (This assumes you're not using a computer script, which can probably calculate the range for you anyway.) An IP address is composed of four groups of eight ones and zeros. Each group represents a number from 0 to 255. To convert a number to binary, you can use a reference table or know the value of each binary digit:

Proceeding from left to right, fill in  if the number is at least that value, and subtract that value (if it's not, fill in   and don't subtract). Zum Beispiel, um 240 zu berechnen.


 * 1) 240 ist mindestens 128, also setze   und subtrahiere 128.
 * 2) 112 (240-128) ist mindestens 64, also setze   und subtrahiere 64.
 * 3) 48 (112-64) ist mindestens 32, also setze   und subtrahiere 32.
 * 4) 16 (48-32) ist mindestens 16, also setze   und subtrahiere 16.
 * 5) Da der übrig gebliebene Wert null ist, sind die restlichen Stellen.

Thus, 240 is  because it can be represented as 128+64+32+16+0+0+0+0.

Calculate range

 * 1) Place both IP addresses one atop the other, and count how many starting digits are exactly alike. This is the CIDR suffix.
 * 2) Double-check! Being off by one digit could extend your block by thousands of addresses.

The example below calculates the CIDR range between  and. Note that this is a simple example; some groups of IP addresses do not so neatly fit CIDR suffixes, and need multiple different-sized blocks to block the exact range.


 * IP-Adressen:


 * Zu Binär umwandeln:


 * Zähle identische erste Zahlen:


 * CIDR range :



Tabelle der Beispielreichweiten
The table below shows the IPv4 blocks each CIDR suffix affects. Note that MediaWiki only supports blocking CIDR suffixes 16 - 32 in IPv4 and 19 (formerly 64) - 128 in IPv6 by default (subject to ). See /IPv6 for an IPv6 range table.



Standardbegrenzung
The default MediaWiki installation limits range blocks to no larger than /16 IPv4 rangeblocks (65,536 addresses). To block larger ranges needs to be set accordingly in.

Known problems
One important already-known problem caused by any range-block, is that as side-effect they also block some trusted registered groups, like wiki administrators, users who do not need to be patrolled by others, and trusted bots. Details: T309328

Einzelnachweise

 * Classless Inter-Domain Routing



Externe Links

 * Netmask calculator which helps in making the correct decision for range blocks.
 * Subnet Calculator can help calculate prefix length and subnet mask for IPv4 and IPv6.
 * IP CIDR Calculator
 * ftools/general/ip-range-calc.html - gives you the range you should use when blocking.
 * IPv4 and CIDR Calculator gives you a breakdown of Hosts and IP Range for any Given Mask/CIDR and reverse.