How to get an A.S.N.
What is an ASN and what is it used for?
According to ARIN, an ASN, technically, is:
Autonomous System Numbers (ASNs) are globally unique numbers that are used to identify autonomous systems (ASes), and which enable an AS to exchange exterior routing information between neighboring ASes. An AS is a connected group of IP networks that adhere to a single and clearly defined routing policy.
The main reason that this is used is for redundancy for two different upstream Internet providers. By registering for an ASN, the routing information provided will allow redirecting from one ISP to another.
An ASN is used for routing on the internet, to help distinguish between internal and external routing and/or routing between different Internet providers.
Why would I need an ASN?
If you have two seperate Internet Service Providers, one primary and one for backup, then you may need an ASN. The ASN would allow the routing to change between the two Internet Service Providers without having to reconfigure the routers or any devices with static IP addresses.
How do I get an ASN?
To get an ASN, you must go to Arin's website (www.arin.net), read the information, and fill out the ASN Template on the page and send it to them in e-mail.
Tips for Registering for an ASN
ARIN is very picky about how their template is filled out. Make sure you read the instructions on the template (which are below the area that needs to be filled out). Also, you must provide the routing information about your network to ARIN. Keep in mind, too much information will not hurt the process.