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General IPv6 Topics => IPv6 Basics & Questions & General Chatter => Topic started by: zhaojichang on April 21, 2008, 03:53:21 AM

Title: What is tansit as??
Post by: zhaojichang on April 21, 2008, 03:53:21 AM
 ???can some guy explain transit as to me ? It appears in some paper about IPv6.
Any attention is appreciated!  :)
Title: Re: What is tansit as??
Post by: broquea on April 21, 2008, 09:58:03 AM
???can some guy explain transit as to me ? It appears in some paper about IPv6.
Any attention is appreciated!  :)

Are you referring to an ASN which is allocated to people that register & pay with their RIR? http://en.wikipedia.org/wiki/Autonomous_System_Number
Title: Re: What is tansit as??
Post by: testmonster on April 21, 2008, 12:51:28 PM
???can some guy explain transit as to me ? It appears in some paper about IPv6.
Any attention is appreciated!  :)

The most basic definition is:

transit is when traffic from network A crosses network B to reach network C.

In other words the traffic "transits" network B, who is neither a source or destination of the traffic.

peering is when network A and network B exchange traffic on a settlement free basis (no money exchanged),
and A and B do not announce each other to their peers (which would mean that they are providing transit).

Those are two basic defitions to get you started.  In reality, since each prefix can have different policy
routing, and networks can have different policies in different geographic regions, there can be more complicated
relationships in between (usually not though).

You should go to http://bgp4.as and spend several weeks reading (there is that much material linked to from that site).
It will be well worth it if you are doing analysis of peering and transit relationships on the Internet for IPv6 or IPv4.
Title: Re: What is tansit as??
Post by: zhaojichang on April 21, 2008, 05:48:29 PM
Thank you,testmonster !