Re: Network SLA
I talked to the NOC personnel at a small (compared to North American standards) ISP in Pakistan. They said that their core links are operating at less than 50% utilization most of the time. Under such conditions, violating SLA conditions in the core is unlikely. If such is also the case with most service providers in the North America as well, then why would they even use active measurement such as iPerf or BRIX or Cisco IP SLAs before signing an SLA? Thanks and best regards On Thu, Feb 19, 2009 at 8:50 PM, Saqib Ilyas msa...@gmail.com 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 -- 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
Re: Network SLA
Hmmm. Good point. Perhaps the Internet traffic gets only a small share of the link capacity and the rest is reserved for corporate clients' VPN traffic etc. I was thinking more along the lines of corporate SLAs, not for Internet traffic. On Wed, Apr 15, 2009 at 4:05 PM, Rod Beck rod.b...@hiberniaatlantic.comwrote: Congestion is more common than you think. And by the way, if congestion is not a problem in Pakistan, then why is the VoIP qualit so poor? :) Roderick S. Beck Director of European Sales Hibernia Atlantic 13-15, rue Sedaine, 75011 Paris http://www.hiberniaatlantic.com Wireless: 1-212-444-8829. French Landline: 33+1+4355+8224 French Wireless: 33-6-14-33-48-97. AOL Messenger: GlobalBandwidth rod.b...@hiberniaatlantic.com rodb...@erols.com ``Unthinking respect for authority is the greatest enemy of truth.'' Albert Einstein. -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com msa...@gmail.com] Sent: Wed 4/15/2009 11:22 AM To: nanog@nanog.org Subject: Re: Network SLA I talked to the NOC personnel at a small (compared to North American standards) ISP in Pakistan. They said that their core links are operating at less than 50% utilization most of the time. Under such conditions, violating SLA conditions in the core is unlikely. If such is also the case with most service providers in the North America as well, then why would they even use active measurement such as iPerf or BRIX or Cisco IP SLAs before signing an SLA? Thanks and best regards On Thu, Feb 19, 2009 at 8:50 PM, Saqib Ilyas msa...@gmail.com 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 -- 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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
On Wed, Apr 15, 2009 at 7:10 AM, Saqib Ilyas msa...@gmail.com wrote: Hmmm. Good point. Perhaps the Internet traffic gets only a small share of the link capacity and the rest is reserved for corporate clients' VPN traffic etc. I was thinking more along the lines of corporate SLAs, not for Internet traffic. For private, point to point, line, I agree with a previous posting on the subject: As for the rest, CIR, Latency, Jitter, Loss . this can be tested prior to customer handover with any number of tools and protocols including IEEE 802.11ag/ah, ITU-T 1731, IETF RFC2544. -Rich Andreas Asking to receive the testing report as part of an acceptance process is not unusual. For corporate IP service, you may want to measure end to end performance and not get too specific in the core. Writing an SLA against city pair performance is a responsible method to do this e.g. Islamabad-Kabol not equal to more than 1ms. That should encompass everything along the required path(s) and hopefully incent your provider to keep their network up to snuff and their MTTR low. You may also consider codifying the MTTR i.e. MTTR = 2 Hours or service credit. (Again, depends on your economic power). Don't forget that your power to negotiate SLA's with service credits is proportionate to the size of the purchase. Buying 10 Mb/s vs. 10 Gb/s services are two different types of economics when it comes to SLA. Best, Martin -- Martin Hannigan mar...@theicelandguy.com p: +16178216079 Power, Network, and Costs Consulting for Iceland Datacenters and Occupants
RE: Network SLA
From the network operators' standpoint, designing a network that operates at 50% utilization (without using ponderous QoS schemes) assumes that there is no random queuing behavior in the network that can result in dropped packets and large variations in packet arrival jitter. An active measurement tool such as BRIX gathers empirical data for packet drops and jitter from which accurate predictions about network behavior can be made. Think of active measurement tools as a means of implementing a scientific approach to determining network behavior. From the users' standpoint, BRIX can be used to validate the service providers' contractual SLA, and provide empirical data to support SLA violation penalties. -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com] Sent: Wednesday, April 15, 2009 4:11 AM To: nanog@nanog.org Subject: Re: Network SLA Hmmm. Good point. Perhaps the Internet traffic gets only a small share of the link capacity and the rest is reserved for corporate clients' VPN traffic etc. I was thinking more along the lines of corporate SLAs, not for Internet traffic. On Wed, Apr 15, 2009 at 4:05 PM, Rod Beck rod.b...@hiberniaatlantic.comwrote: Congestion is more common than you think. And by the way, if congestion is not a problem in Pakistan, then why is the VoIP qualit so poor? :) Roderick S. Beck Director of European Sales Hibernia Atlantic 13-15, rue Sedaine, 75011 Paris http://www.hiberniaatlantic.com Wireless: 1-212-444-8829. French Landline: 33+1+4355+8224 French Wireless: 33-6-14-33-48-97. AOL Messenger: GlobalBandwidth rod.b...@hiberniaatlantic.com rodb...@erols.com ``Unthinking respect for authority is the greatest enemy of truth.'' Albert Einstein. -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com msa...@gmail.com] Sent: Wed 4/15/2009 11:22 AM To: nanog@nanog.org Subject: Re: Network SLA I talked to the NOC personnel at a small (compared to North American standards) ISP in Pakistan. They said that their core links are operating at less than 50% utilization most of the time. Under such conditions, violating SLA conditions in the core is unlikely. If such is also the case with most service providers in the North America as well, then why would they even use active measurement such as iPerf or BRIX or Cisco IP SLAs before signing an SLA? Thanks and best regards On Thu, Feb 19, 2009 at 8:50 PM, Saqib Ilyas msa...@gmail.com 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 -- 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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
I'm back! Thanks again to all those who replied. I am wondering how a service provider might assess availability or reliability figures using active measurements. Granted that one could set up traffic generators between 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. 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, is it not? Thanks and best regards On Fri, Mar 13, 2009 at 7:34 PM, Athanasios Douitsis aduit...@gmail.comwrote: 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 developed at 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_andr...@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:msa...@gmail.com] Sent: Saturday, March 07, 2009 6:12 AM To: nanog@nanog.org Subject: Re: Network SLA 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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
On 18.03.2009, at 12:20, Saqib Ilyas wrote: I'm back! Thanks again to all those who replied. I am wondering how a service provider might assess availability or reliability figures using active measurements. Granted that one could set up traffic generators between 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, is it not? You need a year of measurement. Thanks and best regards On Fri, Mar 13, 2009 at 7:34 PM, Athanasios Douitsis aduit...@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 developed at 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_andr...@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:msa...@gmail.com] Sent: Saturday, March 07, 2009 6:12 AM To: nanog@nanog.org Subject: Re: Network SLA 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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
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 developed at 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_andr...@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:msa...@gmail.com] Sent: Saturday, March 07, 2009 6:12 AM To: nanog@nanog.org Subject: Re: Network SLA 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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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
RE: Network SLA
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:msa...@gmail.com] Sent: Saturday, March 07, 2009 6:12 AM To: nanog@nanog.org Subject: Re: Network SLA 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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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
RE: Network SLA
We use BRIX for SLA's by measuring round trip times, jitter, and packet loss across all of our backbone links. In conjunction with a traffic generator to add background traffic, and potentially invoke queueing on interfaces, we have found that BRIX enables us to accurately predict the behavior of new applications, particularly multicast and HD video, without the need to implement elaborate QoS configurations. BRIX is now owned by EXFO, a fiber optic test equipment manufacturer. Low values for rtt, jitter, and packet loss imply a relatively queue-free network, which makes confident predictions about network behavior easier. When we last looked at the technology, the Cisco IP SLA probes did not capture a random distribution of network events, as the probes are triggered every N minutes. BRIX randomizes the probes within a configurable window, so that, over time, all time intervals are covered by the accumulated probes. -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com] Sent: Saturday, March 07, 2009 3:12 AM To: nanog@nanog.org Subject: Re: Network SLA 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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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
Re: Network SLA
What products/services do you use for traffic generation? Also what sort of testing methodology do you use? As for random probes that certainly seems like a nice feature. Holmes,David A wrote: We use BRIX for SLA's by measuring round trip times, jitter, and packet loss across all of our backbone links. In conjunction with a traffic generator to add background traffic, and potentially invoke queueing on interfaces, we have found that BRIX enables us to accurately predict the behavior of new applications, particularly multicast and HD video, without the need to implement elaborate QoS configurations. BRIX is now owned by EXFO, a fiber optic test equipment manufacturer. Low values for rtt, jitter, and packet loss imply a relatively queue-free network, which makes confident predictions about network behavior easier. When we last looked at the technology, the Cisco IP SLA probes did not capture a random distribution of network events, as the probes are triggered every N minutes. BRIX randomizes the probes within a configurable window, so that, over time, all time intervals are covered by the accumulated probes. -- Charles N Wyble char...@thewybles.com (818)280-7059 http://charlesnw.blogspot.com CTO SocalWiFI.net
Re: Network SLA
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? 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 regards On Mon, Feb 23, 2009 at 1:19 PM, Zartash Uzmi zart...@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 netfort...@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
Re: Network SLA
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 zart...@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 netfort...@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
Re: Network SLA
On Sat, Mar 07, 2009 at 12:26:45PM +0100, Chris Meidinger wrote: 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. Or for more sophisticated matricies of spot-checks, BWCTL (http://www.nanog.org/meetings/nanog43/presentations/Boote_tools_N43.pdf) 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. While Birx is awesome and a cisco-heavy site certainly should use rtr/ipsla in their mix, don't underestimate the value of a lightweight system built on smokeping (http://oss.oetiker.ch/smokeping/). Choose the right set of tools for your budget and environment. Cheers! Joe -- RSUC / GweepNet / Spunk / FnB / Usenix / SAGE
Re: Network SLA
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 netfort...@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
Network SLA
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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
RE: Network SLA
Availability cannot be calculated in advance. It typically is based on historical component failure information. Sound design ensures redundancy and eliminates single point of failure. As for the rest, CIR, Latency, Jitter, Loss . this can be tested prior to customer handover with any number of tools and protocols including IEEE 802.11ag/ah, ITU-T 1731, IETF RFC2544. Hand-helds are typically not cost effective. Rich Andreas Comcast Network Engineering -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com] Sent: Thursday, February 19, 2009 10:50 AM To: nanog@nanog.org Subject: Network SLA 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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
RE: Network SLA
Maybe the best way of addressing this is knowing exactly what we need to measure- if IP traffic, services or processes. If the timescale of a process (ie: MTTR's)and/or procedure or just data and/or voice traffic from point A to B. Or just scoping the measurments as being the performance of the core network, or only related to usage based service. And that takes us to the TMN model and to the bottom-up approach starting w/ the FCAPs. you have fereware, shareware and licenced tools or most likely specific vendor-related tools and only linked to one vendor or one type of equipment. I am sure you've heard of RRD/MRTG, just like a few others that normally sit on the botton tier and have an upstream chain correlating the events. Most times the options are about suitablity and what the software version is prepared to report on so they are seen as more suitable to customers. --- On Thu, 2/19/09, Andreas, Rich rich_andr...@cable.comcast.com wrote: From: Andreas, Rich rich_andr...@cable.comcast.com Subject: RE: Network SLA To: Saqib Ilyas msa...@gmail.com, nanog@nanog.org Date: Thursday, February 19, 2009, 5:59 PM Availability cannot be calculated in advance. It typically is based on historical component failure information. Sound design ensures redundancy and eliminates single point of failure. As for the rest, CIR, Latency, Jitter, Loss . this can be tested prior to customer handover with any number of tools and protocols including IEEE 802.11ag/ah, ITU-T 1731, IETF RFC2544. Hand-helds are typically not cost effective. Rich Andreas Comcast Network Engineering -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com] Sent: Thursday, February 19, 2009 10:50 AM To: nanog@nanog.org Subject: Network SLA 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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
On Thu, 19 Feb 2009, Saqib Ilyas wrote: 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. IME, the administrators don't have anything to do with what is signed. The company chooses what SLAs to sign with customers (typically whatever the customer requests, possibly with various levels of pricing for different agreements), but the operational staff are not involved. If you're lucky, you have this information before you build and can -try- to build to suite. But most times, the SLAs are signed after you've built, and everyone just crosses their fingers. IME. ..david --- david raistrickhttp://www.netmeister.org/news/learn2quote.html dr...@icantclick.org http://www.expita.com/nomime.html
RE: Network SLA
We use the BRIX active measurement instrumentation product to measure round-trip, jitter, and packet loss SLA conformity. -Original Message- From: Saqib Ilyas [mailto:msa...@gmail.com] Sent: Thursday, February 19, 2009 7:50 AM To: nanog@nanog.org Subject: Network SLA 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 -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Re: Network SLA
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
