nanog mailing list archives
Re: Network SLA
From: Chris Meidinger <cmeidinger () sendmail com>
Date: Wed, 18 Mar 2009 13:24:38 +0100
On 18.03.2009, at 12:20, Saqib Ilyas wrote:
I'm back! Thanks again to all those who replied. I am wondering how aservice provider might assess availability or reliability figures usingactive measurements. Granted that one could set up traffic generatorsbetween the two PoPs which will be connected to a customer's sites, and then after a day of test traffic, I can look for downtimes and restoration times.
This is an exact description of IPSLA. Of course you don't know whether a maximum bandwidth was in fact available, because you don't want to saturate the link.
But a one day estimate is not a good estimate for what the service provider is promising, which is usually "maximum of 10 hours downtime in an year", isit not?
You need a year of measurement.
Thanks and best regardsOn Fri, Mar 13, 2009 at 7:34 PM, Athanasios Douitsis <aduitsis () gmail com >wrote:Anyone interested in setting up his own IP SLA probes by hand and then collect the measurements into a database, can use a Perl tool we developedat 2005: http://sourceforge.net/projects/saa-collector It's rather old (SAA got renamed into IPSLA in the meantime) and, in retrospect, the code is a little rough around the edges, but it's nevertheless usable. Regards, Athanasios On Wed, Mar 11, 2009 at 10:20 PM, Andreas, Rich < Rich_Andreas () cable comcast com> wrote:I have found that Cisco IPSLA is heavily used in the MSO/Service Provider Space. Juniper has equivalent functionality via RPM. Rich -----Original Message----- From: Saqib Ilyas [mailto:msaqib () gmail com] Sent: Saturday, March 07, 2009 6:12 AM To: nanog () nanog org Subject: Re: Network SLAI must thank everyone who has answered my queries. Just a couple moreshort questions.For instance, if one is using MRTG, and wants to check if we can meeta 1 Mbps end-to-end throughput between a couple of customer sites, I believe you would need to use some traffic generator tools, because MRTG merely imports counters from routers and plots them. Is that correct? We've heard of the BRIX active measurement tool in replies to my earlier email. Also, I've found Cisco IP SLA that also sends traffic into the service provider network and measures performance. How many people really use IP SLA feature? Thanks and best regardsOn Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi <zartash () gmail com> wrote:As I gather, there is a mix of answers, ranging from "building theresourcesaccording to requirements and HOPE for the best" to "use of arguablysophisticated tools and perhaps sharing the results with the legal department".I would be particularly interested in hearing the service providers'viewpoint on the following situation.Consider a service provider with MPLS deployed within its own network.(A) When the SP enters into a relation with the customer, does the SPestablish new MPLS paths based on customer demands (this is perhapssimilarto "building" based on requirements as pointed out by David)? If yes,between what sites/POPs? I assume the answer may be differentdepending upona single-site customer or a customer with multiple sites. (B) For entering into the relationship for providing X units ofbandwidth(to another site of same customer or to the Tier-1 backbone), does theSPuse any wisdom (in addition to MRTG and the likes)? If so, whatscientificparameters are kept in mind? (C) How does the customer figure out that a promise for X units ofbandwidthis maintained by the SP? I believe customers may install somemeasuringtools but is that really the case in practice? Thanks, ZartashOn Fri, Feb 20, 2009 at 1:16 AM, Stefan <netfortius () gmail com> wrote:Saqib Ilyas wrote:Greetings I am curious to know about any tools/techniques that a serviceprovideruses to assess an SLA before signing it. That is to say, how does an administrator know if he/she can meet what he is promising. Is itbased onexperience? Are there commonly used tools for this? Thanks and best regardsNot necessarily as a direct answer (I am pretty sure there'll beothers onthis list giving details in the area of specific tools andstandards), but Ithink this may be a question (especially considering your end resultconcern: *signing the SLA!) equally applicable to your legaldepartment. Inthe environment we live, nowadays, the SLA could (should?!? ...unfortunately) be "refined" and (at the other end - i.e. receiving)"interpreted" by the lawyers, with possibly equal effects (mostlyfinancialand as overall impact on the business) as the tools we (the technical people) would be using to measure latency, uptime, bandwidth, jitter,etc...Stefan-- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences-- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Current thread:
- Re: Network SLA Saqib Ilyas (Mar 07)
- Re: Network SLA Chris Meidinger (Mar 07)
- Re: Network SLA Joe Provo (Mar 07)
- RE: Network SLA Holmes,David A (Mar 09)
- Re: Network SLA Charles Wyble (Mar 09)
- RE: Network SLA Andreas, Rich (Mar 11)
- Re: Network SLA Athanasios Douitsis (Mar 13)
- Re: Network SLA Saqib Ilyas (Mar 18)
- Re: Network SLA Chris Meidinger (Mar 18)
- Re: Network SLA Athanasios Douitsis (Mar 13)
- Re: Network SLA Chris Meidinger (Mar 07)