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AS top 1024 addresses are marked as private

I have read this article :

[quote]Applying for a public BGP AS number requires the justification of the need for the AS number. For networks that do not have their own block of address space, this may not be possible. For this reason the top 1024 addresses in the BGP AS range are marked as private[/quote].

I got confused by what did he mean by : "the top 1024 addresses-------" ?

My interpretation is : since the range of the private AS from 64512-65535,,if we find the difference between 65535-64512 = 1023,,,,Is this what is meant by : "the top 1024 addresses in the

BGP AS range are marked as private" ??

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Re: AS top 1024 addresses are marked as private

You are correct. Here is another reference:

http://www.avici.com/documentation/HTMLDocs/02223-08_revAA/BGP_Nd32.html

Description: When an autonomous system provides BGP to a single provider, and the routing policy will not be visible to the internet, private autonomous system numbers are used in order to conserve public autonomous system numbers. Private AS numbers are in the range 64512 - 65535. When BGP advertises prefixes to external neighbors, these private AS numbers should be removed.

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Blue

Re: AS top 1024 addresses are marked as private

You are correct. Here is another reference:

http://www.avici.com/documentation/HTMLDocs/02223-08_revAA/BGP_Nd32.html

Description: When an autonomous system provides BGP to a single provider, and the routing policy will not be visible to the internet, private autonomous system numbers are used in order to conserve public autonomous system numbers. Private AS numbers are in the range 64512 - 65535. When BGP advertises prefixes to external neighbors, these private AS numbers should be removed.

Please rate helpful posts.

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