Telecom International HTTP Caching
Good Morning, Telecom would like to advise that over the coming weeks we will be extending our international http caching service. This work should go unnoticed but if you or your customers do experience a loss of international browsing then please contact the Broadband Helpdesk on: adsl_helpdesk(a)xtra.co.nz Please make sure the subject has "HTTP Caching" included so that the Helpdesk can filter on these issues. If you would like to talk to the Helpdesk then please phone: 0800 22 55 98 Please state that you believe this to be an http caching issue when raising the case so that it will be routed to the correct resources. NB. Please note that the service is only in place for Telecom Broadband Customers and "International" in this case is based on the international routing tables, as such some domestic sites may appear to Telecom as international content. If you have any specific questions about the service then please feel free to post the questions on this mailing list and as time allows they will be answered. Regards Paul Tinson Senior Specialist Web App Services Shared & Other IS Operations E paul.tinson(a)telecom.co.nz mailto:paul.tinson(a)telecom.co.nz W www.telecom.co.nz http://www.telecom.co.nz Level 9, 31 Airedale Street Auckland ________________________________ "This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it. Thank you. Please note that this communication does not designate an information system for the purposes of the Electronic Transactions Act 2002."
Hi Paul. I assume customers who are buying global gateway international transit will not be "cached"? From: nznog-bounces(a)list.waikato.ac.nz [mailto:nznog-bounces(a)list.waikato.ac.nz] On Behalf Of Paul Tinson Sent: Tuesday, 11 August 2009 6:16 a.m. To: nznog(a)list.waikato.ac.nz Subject: [nznog] Telecom International HTTP Caching Good Morning, Telecom would like to advise that over the coming weeks we will be extending our international http caching service. This work should go unnoticed but if you or your customers do experience a loss of international browsing then please contact the Broadband Helpdesk on: adsl_helpdesk(a)xtra.co.nzmailto:adsl_helpdesk(a)xtra.co.nz Please make sure the subject has "HTTP Caching" included so that the Helpdesk can filter on these issues. If you would like to talk to the Helpdesk then please phone: 0800 22 55 98 Please state that you believe this to be an http caching issue when raising the case so that it will be routed to the correct resources. NB. Please note that the service is only in place for Telecom Broadband Customers and "International" in this case is based on the international routing tables, as such some domestic sites may appear to Telecom as international content. If you have any specific questions about the service then please feel free to post the questions on this mailing list and as time allows they will be answered. Regards Paul Tinson Senior Specialist Web App Services Shared & Other IS Operations [cid:image001.gif(a)01CA1A7B.11746220] E paul.tinson(a)telecom.co.nzmailto:paul.tinson(a)telecom.co.nz W www.telecom.co.nzhttp://www.telecom.co.nz Level 9, 31 Airedale Street Auckland ________________________________ "This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it. Thank you. Please note that this communication does not designate an information system for the purposes of the Electronic Transactions Act 2002."
That is correct. This service is only for Telecom Broadband Customers and not GGIS/TNZI customers in general. Regards Paul ________________________________ From: Simon Allard [mailto:simon.allard(a)team.orcon.net.nz] Sent: Tuesday, 11 August 2009 11:59 a.m. To: Paul Tinson; nznog(a)list.waikato.ac.nz Subject: RE: [nznog] Telecom International HTTP Caching Hi Paul. I assume customers who are buying global gateway international transit will not be "cached"? From: nznog-bounces(a)list.waikato.ac.nz [mailto:nznog-bounces(a)list.waikato.ac.nz] On Behalf Of Paul Tinson Sent: Tuesday, 11 August 2009 6:16 a.m. To: nznog(a)list.waikato.ac.nz Subject: [nznog] Telecom International HTTP Caching Good Morning, Telecom would like to advise that over the coming weeks we will be extending our international http caching service. This work should go unnoticed but if you or your customers do experience a loss of international browsing then please contact the Broadband Helpdesk on: adsl_helpdesk(a)xtra.co.nz Please make sure the subject has "HTTP Caching" included so that the Helpdesk can filter on these issues. If you would like to talk to the Helpdesk then please phone: 0800 22 55 98 Please state that you believe this to be an http caching issue when raising the case so that it will be routed to the correct resources. NB. Please note that the service is only in place for Telecom Broadband Customers and "International" in this case is based on the international routing tables, as such some domestic sites may appear to Telecom as international content. If you have any specific questions about the service then please feel free to post the questions on this mailing list and as time allows they will be answered. Regards Paul Tinson Senior Specialist Web App Services Shared & Other IS Operations E paul.tinson(a)telecom.co.nz mailto:paul.tinson(a)telecom.co.nz W www.telecom.co.nz http://www.telecom.co.nz Level 9, 31 Airedale Street Auckland ________________________________ "This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it. Thank you. Please note that this communication does not designate an information system for the purposes of the Electronic Transactions Act 2002."
On 11/08/2009, at 6:15 AM, Paul Tinson wrote:
NB. Please note that the service is only in place for Telecom Broadband Customers and “International” in this case is based on the international routing tables, as such some domestic sites may appear to Telecom as international content.
Exact implementation isn't that important, but my guess is that these caches sit inside TNZI somewhere, call it an educated guess. Depending on where exactly they sit, there is a problem that has impacted several NZ providers in the past when implementing fully transparent caching. Some conditions: 1) A destination is considered to be international by TNZI 2) The destination hands traffic back over a domestic circuit 3) Domestic inbound does not pass through the devices doing the redirection of 80/TCP traffic The effect is: 1) Outbound SYN gets sent to a cache, which regenerates it. 2) Inbound SYN+ACK comes in, and goes straight to the customer. 3) Things break in TCP There are a couple of other asymmetric routing things that can break caching as well. These sort of things are kind of unique to markets like NZ, where we differentiate between international and domestic - at least in our SP networks. Anyway, is this likely to impact the TNZ caching, or are the caches in a place so this doesn't impact them? -- Nathan Ward
The scenario that you highlight below does affect us and is one of the reasons we are actively informing the wider operator community about the caches and our implementation of them. As you quite rightly point out there are a number of asymmetric routing situations that can occur, while we are making every attempt to mitigate these situations we may miss something. That is where forums like this will be useful in helping us to resolve and maybe avoid them. If any one on the list has a fault of this nature please let us know so that we can investigate. The most likely manifestation of this will be timeouts on 'international' sites. I hope this answers your question. Regards Paul -----Original Message----- From: nznog-bounces(a)list.waikato.ac.nz [mailto:nznog-bounces(a)list.waikato.ac.nz] On Behalf Of Nathan Ward Sent: Wednesday, 12 August 2009 12:17 a.m. To: nznog Subject: Re: [nznog] Telecom International HTTP Caching On 11/08/2009, at 6:15 AM, Paul Tinson wrote:
NB. Please note that the service is only in place for Telecom Broadband Customers and "International" in this case is based on the international routing tables, as such some domestic sites may appear to Telecom as international content.
Exact implementation isn't that important, but my guess is that these caches sit inside TNZI somewhere, call it an educated guess. Depending on where exactly they sit, there is a problem that has impacted several NZ providers in the past when implementing fully transparent caching. Some conditions: 1) A destination is considered to be international by TNZI 2) The destination hands traffic back over a domestic circuit 3) Domestic inbound does not pass through the devices doing the redirection of 80/TCP traffic The effect is: 1) Outbound SYN gets sent to a cache, which regenerates it. 2) Inbound SYN+ACK comes in, and goes straight to the customer. 3) Things break in TCP There are a couple of other asymmetric routing things that can break caching as well. These sort of things are kind of unique to markets like NZ, where we differentiate between international and domestic - at least in our SP networks. Anyway, is this likely to impact the TNZ caching, or are the caches in a place so this doesn't impact them? -- Nathan Ward _______________________________________________ NZNOG mailing list NZNOG(a)list.waikato.ac.nz http://list.waikato.ac.nz/mailman/listinfo/nznog
participants (3)
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Nathan Ward -
Paul Tinson -
Simon Allard