BGP Peers as basis of available routes
Hi! We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider. In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??) Thanks. -- -nathan
Hi! Dont mix up peering and transit connections! That you dont see that route on a lookingglass doesnt mean much. Only Could tell you they dont transit there. Its all depending what you definiëren with available routes. If i peer with all ISP's in a specific area and your looking glass isnt licated there does that mean its bad? You need to know much more. If your customers are local there its even prefered. Its never that black/white ...its depending on your needs! Thanks, Raymond Dijkxhoorn, Prolocation Op 19 okt. 2011 om 08:46 heeft "Nathanael C. Cariaga" <nccariaga@stluke.com.ph> het volgende geschreven:
Hi!
We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider.
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Thanks.
-- -nathan
Hi. Thanks for the prompt response. Actually our requirement is to find a webhosting provider whose routes are widely advertised locally and regionally. This is why I thought of using bgp as a basis studying the availability of routes of the hosting provider. -nathan On 10/19/2011 3:00 PM, Raymond Dijkxhoorn wrote:
Hi!
Dont mix up peering and transit connections!
That you dont see that route on a lookingglass doesnt mean much. Only Could tell you they dont transit there.
Its all depending what you definiëren with available routes.
If i peer with all ISP's in a specific area and your looking glass isnt licated there does that mean its bad? You need to know much more. If your customers are local there its even prefered.
Its never that black/white ...its depending on your needs!
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 08:46 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi!
We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider.
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Thanks.
-- -nathan
Hi! You wont see those local peerings unless all those providers have looking glasses. So thats not gonna work out in this case. You will only see who they transit with... Thanks, Raymond Dijkxhoorn, Prolocation Op 19 okt. 2011 om 09:21 heeft "Nathanael C. Cariaga" <nccariaga@stluke.com.ph> het volgende geschreven:
Hi.
Thanks for the prompt response. Actually our requirement is to find a webhosting provider whose routes are widely advertised locally and regionally. This is why I thought of using bgp as a basis studying the availability of routes of the hosting provider.
-nathan
On 10/19/2011 3:00 PM, Raymond Dijkxhoorn wrote:
Hi!
Dont mix up peering and transit connections!
That you dont see that route on a lookingglass doesnt mean much. Only Could tell you they dont transit there.
Its all depending what you definiëren with available routes.
If i peer with all ISP's in a specific area and your looking glass isnt licated there does that mean its bad? You need to know much more. If your customers are local there its even prefered.
Its never that black/white ...its depending on your needs!
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 08:46 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi!
We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider.
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Thanks.
-- -nathan
Ok. Thanks for the information :) So that would mean that to answer my question, I would need to determine the web hosting provider who has the most number of peers and most number of transit providers? -nathan On 10/19/2011 3:20 PM, Raymond Dijkxhoorn wrote:
Hi!
You wont see those local peerings unless all those providers have looking glasses. So thats not gonna work out in this case. You will only see who they transit with...
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 09:21 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi.
Thanks for the prompt response. Actually our requirement is to find a webhosting provider whose routes are widely advertised locally and regionally. This is why I thought of using bgp as a basis studying the availability of routes of the hosting provider.
-nathan
On 10/19/2011 3:00 PM, Raymond Dijkxhoorn wrote:
Hi!
Dont mix up peering and transit connections!
That you dont see that route on a lookingglass doesnt mean much. Only Could tell you they dont transit there.
Its all depending what you definiëren with available routes.
If i peer with all ISP's in a specific area and your looking glass isnt licated there does that mean its bad? You need to know much more. If your customers are local there its even prefered.
Its never that black/white ...its depending on your needs!
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 08:46 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi!
We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider.
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Thanks.
-- -nathan
Hi!
Ok. Thanks for the information :) So that would mean that to answer my question, I would need to determine the web hosting provider who has the most number of peers and most number of transit providers?
You wont see those local peerings unless all those providers have looking glasses. So thats not gonna work out in this case. You will only see who they transit with...
I cant answer that, only you can. If that hosting provider has many peers but your customers are not behind them its of no use. But generally a hosting provider with many local peers, either public or private -might have- ok connections ;) For example if they private peer with 10 mbps and the other one has 10 gbps public peering... There isnt a real answer to your question. Its based on your own buisiness needs and decisions on those. Bye, Raymond.
On Wednesday, October 19, 2011 09:35:04 AM Nathanael C. Cariaga wrote:
Ok. Thanks for the information :) So that would mean that to answer my question, I would need to determine the web hosting provider who has the most number of peers and most number of transit providers?
what i found usefull is to check the autnum objects in whois, as many document their peerings and transits there. robtex has also some of this info, in a webinterface... also helpful was peeringdb - you can lookup indvidual ASs without logging in like this http://as<asnumber>.peeringdb.com/ it may give you an indication as to which exchanges your (potential) provider is present at - though not all providers have a / maintain their peeringdb record. HTH kind regards Thilo
-nathan
On 10/19/2011 3:20 PM, Raymond Dijkxhoorn wrote:
Hi!
You wont see those local peerings unless all those providers have looking glasses. So thats not gonna work out in this case. You will only see who they transit with...
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 09:21 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi.
Thanks for the prompt response. Actually our requirement is to find a webhosting provider whose routes are widely advertised locally and regionally. This is why I thought of using bgp as a basis studying the availability of routes of the hosting provider.
-nathan
On 10/19/2011 3:00 PM, Raymond Dijkxhoorn wrote:
Hi!
Dont mix up peering and transit connections!
That you dont see that route on a lookingglass doesnt mean much. Only Could tell you they dont transit there.
Its all depending what you definiëren with available routes.
If i peer with all ISP's in a specific area and your looking glass isnt licated there does that mean its bad? You need to know much more. If your customers are local there its even prefered.
Its never that black/white ...its depending on your needs!
Thanks, Raymond Dijkxhoorn, Prolocation
Op 19 okt. 2011 om 08:46 heeft "Nathanael C. Cariaga"<nccariaga@stluke.com.ph> het volgende geschreven:
Hi!
We're currently evaluating web hosting providers in the APAC region and one of the criteria that we are currently considering is the availability of routes going to the web hosting provider.
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Thanks.
-- -nathan
Ok. Thanks for the information :) So that would mean that to answer my question, I would need to determine the web hosting provider who has the most number of peers and most number of transit providers?
if i was choosing a hosting provider, many other considerations would come before this randy
On Wed, 19 Oct 2011 15:21:27 +0800, "Nathanael C. Cariaga" said:
Thanks for the prompt response. Actually our requirement is to find a webhosting provider whose routes are widely advertised locally and regionally.
That's different from who the provider peers with. We (AS1312) don't peer with much of anybody, but I *hope* our routes are pretty widely advertised. Anybody *not* seeing routes for AS1312? (And yes, most of the routes end up going through one or another of MATP's PoP's). So what failure mode are you trying to protect against by finding a provider with a lot of routes? I suspect there's probably a better metric to deal with the actual concern...
On Oct 19, 2011, at 3:00 AM, Raymond Dijkxhoorn wrote:
Dont mix up peering and transit connections!
I've nearly given up on this. I've heard many a small provider say they are "Peering" with level3 when they mean "we are buying transit from Level3". Many people equate having BGP up with them to mean something else. - Jared
On 10/19/2011 12:48 PM, Jared Mauch wrote:
On Oct 19, 2011, at 3:00 AM, Raymond Dijkxhoorn wrote:
Dont mix up peering and transit connections!
I've nearly given up on this. I've heard many a small provider say they are "Peering" with level3 when they mean "we are buying transit from Level3".
Many people equate having BGP up with them to mean something else.
And yet I might pay for transit from Sprint, but decide to limit routes to just between us (which is peering, but technically I'm paying for transit). Terminology has always been a blast. Jack
On Wed, Oct 19, 2011 at 01:20:42PM -0500, Jack Bates wrote:
On 10/19/2011 12:48 PM, Jared Mauch wrote:
On Oct 19, 2011, at 3:00 AM, Raymond Dijkxhoorn wrote:
Dont mix up peering and transit connections!
I've nearly given up on this. I've heard many a small provider say they are "Peering" with level3 when they mean "we are buying transit from Level3".
Many people equate having BGP up with them to mean something else.
And yet I might pay for transit from Sprint, but decide to limit routes to just between us (which is peering, but technically I'm paying for transit).
Terminology has always been a blast.
Jack
actually, its pretty clear. peer - exchange routes with a neighbor (BGP/OSPF/ISIS/EGP/Static). transit - your neighbor agrees to send your routes to -their- neighbors. peering you can control, transit is controlled by a third party. so Jack, you could pay Sprint for transit (they propogte your routes elsewhere) and then insist on no-export for the routes you give them.. -IF- Sprint honours your no-export, then your just peering, regardless of what you are paying for. /bill
On Wed, Oct 19, 2011 at 2:46 AM, Nathanael C. Cariaga <nccariaga@stluke.com.ph> wrote:
In this regard, I would like to ask for your idea regarding this. Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Hi Nathan, BGP is a distance-vector protocol. In other words, when BGP is advertised on a link from one AS to another, only the "best" distance to a particular route is offered. If A and B both advertise the web hosting provider's (WHP's) route to D and A's distance is better then D won't advertise B's WHP route to A but it will advertise A's WHP route to B. Thus a looking glass at B will see both routes in the BGP RIB, but a looking glass at A will only see A's route. With more AS's between A and B than just D, it's possible (even likely) that neither A nor B will see the others' route during normal operation. Should WHP's connection to A drop, D will find that B's distance is now better and B's route to WHP will be newly advertised to A. A, then having no other connection to WHP, will accept the route via D to B, and pass it onward. When we talk about the BGP table "converging" after a change, this is the process we're talking about. Even if A and B are directly connected, if WHP sets its initial "distance" via B worse than via A, B will decide that A has a better distance to WHP and won't advertise its own version of the route to anyone else at all. And that's before you consider local prefs, communities and other mechanisms for fine-tuning route propagation. And, even if A, B and C have multiple routes in the BGP RIB, generally only one of those routes will be selected for the packet forwarding FIB. So, a traceroute from B to WHP may travel via A even though B is directly connected to WHP. Long story short, if WHP is connected to A, B and C then A, B and C should each see their own direct route to WHP in the BGP RIB, but there's no guarantee that anybody else will see more than one of the three at any given time. Regards, Bill Herrin -- William D. Herrin ................ herrin@dirtside.com bill@herrin.us 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On Oct 18, 2011, at 11:46 PM, Nathanael C. Cariaga wrote:
Is it safe to conclude that the web hosting provider's available routes would would depend on the peers who are advertising their AS / network? (i.e if web hosting provider claims that they are peering with telco a, b, c but as seen from a third party looking glass, only C is seen advertising the web hosting provider network that would mean web hosting provider is effectively utilizing c as their upstream??)
Modulo a lot of nit-picking caveats, this would indicate that they are purchasing transit from C, while they may or may not be peering with A and B. If a customer of A or B is able to reach them in a single AS-hop, but A and B are not advertising a route to C to looking-glasses or their own peers or transit providers, then A and B are peers, but not transit providers, to the web host.
I would need to determine the web hosting provider who has the most number of peers and most number of transit providers?
A large number of transit providers has been shown, both theoretically and experimentally, to _decrease_ uptime, because of greater route-convergence times when there are more parallel paths to a destination. Your mileage may vary, but the optimum number is usually somewhere around three transit providers. The number of peers, though, and more to the point, the number of routes acquired through peering, is an excellent measure of how large and how long an ISP (in this case a web-hoster) has been in business. That shouldn't be your only measure of quality, however. It may be that reliability of power, competence of remote-hands, and flexibility to accommodate your needs are more important than how the packets get delivered. -Bill -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (Darwin) iQIcBAEBCAAGBQJOnwB7AAoJEG+kcEsoi3+H4hEQAKecuMs/sXjXMqpuGaZ/I4+W ZZze/q/pmQskfrJ8l2lWkiv+h0YUlcR9uBEJALmsAZMLwtZwlWPBWO7EgHBXbhFr rA++bM6cjyX8NHER2eAtjmp9ERL4pOV3CoIz6WlMJEfuETmF2equoyFN1yoRRJCm x87HeXBkK3vram37eZx90GYXOnnlqqYkTTwoU6BqGU1aFQ1WmCr6udZ8+PDU1f55 xpSsU4OdQv+KjIVsUvaAuBVOAozZ2PO7VP8Lx1FGMuR7yFziliK1GYmlF7CVB6Aw rvZJNPPXQHx74FBWqmGSQrq3slrE++6vUKUvylr4Rz3oV5B/JXFgzgFTVyTtD63B Fl8zkuSFLXgiot8wMVJXo0XHCHbt8kLelBdVooKULgiNxh9UznxcELiB0/M6bBF0 wos2sr56MxwHKneY+yek+CJ9lC5teh+e37r/Lup8PK3JBzYMCA81/uKaFxFTQLWA YNRzudJ3W1kOmwvtkBUPISX1hGBLgzrREmm+2DXQrC4lWSgKsH4p+lyHnx3TR0vv ZRsgUQ9ErBAKYd303bP8Z1KBlK7EkTKBr4FsK0lQcikDR3NArMXTCi4x6WSZkiqZ 9xixEa3rIuI7UwsgFIZibKHK15PunoCQSZQnEF8lKeqWbSsLbKQ3icVP7zBgOB8J ycKYwKtsWQc2ayyvpWs2 =zi6u -----END PGP SIGNATURE-----
participants (10)
-
Bill Woodcock -
bmanning＠vacation.karoshi.com -
Jack Bates -
Jared Mauch -
Nathanael C. Cariaga -
Randy Bush -
Raymond Dijkxhoorn -
Thilo Bangert -
Valdis.Kletnieks＠vt.edu -
William Herrin