Re: Network SLA

[Chris Meidinger <cmeidinger () sendmail com>]

Saqib,

On 07.03.2009, at 12:12, Saqib Ilyas wrote:

> I must thank everyone who has answered my queries. Just a couple more
> short questions.
> For instance, if one is using MRTG, and wants to check if we can meet
> a 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?

Yes, if you want to do a test bandwidth, iperf should probably be your  
first stop.

> 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?

I know a lot of people that use IPSLA. Remember, that you set it up  
between two routers or higher-end switches and it constantly tests  
that connection. However, IPSLA is the wrong tool for a one-off test  
of whether you can push a Mbps from site A to site B, because you need  
to saturate the link to do that test. IPSLA is great for monitoring  
things like jitter.

HTH,

Chris

> Thanks and best regards
>
> On 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 the  
> > resources
> > according to requirements and HOPE for the best" to "use of arguably
> > sophisticated 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 SP
> > establish new MPLS paths based on customer demands (this is perhaps  
> > similar
> > to "building" based on requirements as pointed out by David)? If yes,
> > between what sites/POPs? I assume the answer may be different  
> > depending upon
> > a single-site customer or a customer with multiple sites.
> >
> > (B) For entering into the relationship for providing X units of  
> > bandwidth
> > (to another site of same customer or to the Tier-1 backbone), does  
> > the SP
> > use any wisdom (in addition to MRTG and the likes)? If so, what  
> > scientific
> > parameters are kept in mind?
> >
> > (C) How does the customer figure out that a promise for X units of  
> > bandwidth
> > is maintained by the SP? I believe customers may install some  
> > measuring
> > tools but is that really the case in practice?
> >
> > Thanks,
> > Zartash
> >
> > On 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 service  
> > > > provider
> > > > uses
> > > > 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 it  
> > > > based on
> > > > experience? Are there commonly used tools for this?
> > > > Thanks and best regards
> > > Not necessarily as a direct answer (I am pretty sure there'll be  
> > > others on
> > > this list giving details in the area of specific tools and  
> > > standards), but I
> > > think this may be a question (especially considering your end result
> > > concern: *signing the SLA!) equally applicable to your legal  
> > > department. In
> > > the 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 (mostly  
> > > financial
> > > and 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