Talk:Border Gateway Protocol
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See archive of May, 2006 "Requested move" discussion at /Capitalization
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[edit] IPv6 advantage
I removed this text:
- One of the many advantages of IP version 6's huge address space potentially is to solve this by better use of route aggregation.
because it's not really true, and it would be confusing to explain why in a page that's basically about something else.
There is no mechanism associated with that larger address space that is explicitly designed to reduce the size of routing tables. In fact, the larger address space would allow for larger routing tables if it is not managed properly.
The two issues (address space size, and degree of aggregation) are totally orthogonal.
There is a mechanism that is part of IPv6 that might provide some help, the fast renumbering stuff. However, for that to be of any use, people must be willing to renumber their networks, to produce greater aggregation in the routing tables, and there is no empirical evidence that this will actually happen. However, this has little to do with the size of the address (only that large addresses allow use of hardware derived low-order parts - except that this is now deprecated on privacy grounds).
Similarly, if Multi6 actually agrees on a mechanism, and it gets OK'd by the IPv6 community, and it is adopted, implemeneted, and deployed, then that would help too - but again, this has nothing to do with the size of addresses. Noel 20:55, 14 Sep 2004 (UTC)
[edit] Terms: path vector versus vector routing protocol
"path vector".. don't you mean "vector routing protocol"? I am not confident enough to edit it myself.
Rembering my courses on BGP, I think that it's been given many names, e.g. depending on whether people wanted to insult it (for marketing reasons e.g). It's a kind of vector routing protocol (since it only knows next hop and a kind of sophisticated cost, it doesn't know the whole link through to the end) but it's really much more than a vector routing protocol since beyond direction and fixed cost, it also knows the "ASPATH" which lists the networks that will be traversed in that direction. This allows political decisions (I would rather my traffic didn't go across ZUZONET since they monitor traffic). That's why it is sometimes called something like a "path vector" protocol see Google... first several links look good. Mozzerati 05:59, 2004 May 27 (UTC)
- "path vector" is the proper term, invented by Yakov Rekhter distinguish it from "destination vector" protocols such as RIP. Noel 20:57, 14 Sep 2004 (UTC)
- I was not sufficiently precise above, I wrote in haste, sorry. "path vector" is a sub-set of "destination vector". Note also that "distance vector" != "destination vector".
- All "destination vector" means is that the data that is passed from one router to another is a table (vector) of information about destinations; about basically (modulo policy constraints) all destinations, in fact. (Think of it as the complete routing table.) Contrast this with link-state routing (which I recently re-wrote in a major way to provide a precise, and hopefully readable, description), which is fundamentally radically different.
- BGP does carry the complete AS path for each destination (for loop-prevention as well as making it available for policy decisions - initially the former was the more important, but nowadays the latter is), so your statement ("it doesn't know the whole link through to the end") isn't quite correct - yes, the BGP information doesn't specify each individual router in the path, but it does show which AS's are in the path which packets to that destination will take.
- (Sigh, I need to redo the destination-vector routing page too, and also distance-vector routing, to make them all equally precise. The history of the terminology is a little confusing. At first there was only "distance" vector, which implied that the only data in each element of the vector, other that the destination identity, was a single metric, the "distance". [That's very ancient terminology, I'd have to do some research to track down its source.] Then Yakov came up with the PV term to emphasize that each vector element included an entire path. So then we started calling the entire class "destination" vector [in part so that the "DV" acronym didn't have to change ;-] to emphasize that its fundamental nature - as opposed to LS - hadn't changed. You still gave your neighbour the entire routing table, and the path selection computation was still a distributed one, as opposed to LS, where the entire path-selection algorithm runs in parallel on each node.)
- I hope this makes things a bit clearer (until I get around to re-writing those two articles). Noel (talk) 17:40, 27 Dec 2004 (UTC)
[edit] All ISPs?
Not all ISPs use BGP - smaller ISPs (eg tier 3) may be part of the upstream provider's AS. Unless someone objects, I'll soon amend the relevant text.
--Thedangerouskitchen 11:06, 3 Apr 2005 (UTC)
Seems like a good idea to me... That being said, the ISPs that don't run BGP tend to be very small with only a few exceptions. --Jwvo
[edit] Requested move
In May, 2006, the article was moved to Border gateway protocol. After a "Requested move" discussion, it was moved back to Border Gateway Protocol. See the archive of the discussion at /Capitalization --NealMcB 22:25, 30 May 2006 (UTC)
I summarized the discussion very briefly at: Wikipedia_talk:Naming_conventions_(capitalization)#Capitalizing_standardized_names_for_protocols.2C_etc. and further discussion should probably happen there. --NealMcB 17:15, 31 May 2006 (UTC)
[edit] Expert request: Path Selection not part of standard?
I'm wondering if the secion on path selection is really about the BGP, or about a non-standardized algorithm for using the info that BGP provides. E.g. it says Prefer the path with the highest weight (Only on Cisco routers) but that would clearly not be in a standard. I see no use of the term 'path selection' in RFC 4271. Can someone who knows this stuff better address this? --NealMcB 00:38, 1 June 2006 (UTC)
- ⇒ <SSPecteR> As far as I know, there is no standard for path selection in BSP. The criteria is free for the AS to choose. Someone confirm this. It would be nice to have a section with general preferences to determine the best path. But how it is there (Quote: "BGP uses the following criteria ...") it is wrong. For now, Im taking this area off. ♠ Saturday, 2006-06-10, 06:22 (UTC)
[edit] OpenBGPD... being objective
I have removed the legend "that is much faster and reliable than Zebra or Quagga" in the OpenBGPD link.
We should make a comparison table about routing software.
[edit] AS vs. ASN
AS stands for Autonomous System wheres ASN stands for AS Number. I'll replace incorrect uses of ASN instead of AS.
