North American Network Operators Group|
Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical
Re: Is anyone actually USING IP QoS?
> >_is_ caching, with zero retention time) - w/o associated security and > >scalability problems. Presenting L2/L3 multicasting as the best or the > only > >or even a meaningful way to reduce transmission duplication is quite > wrong. > > research or data to support these assertions? > > and how does caching magically negate security and scalability concerns? > what tools are you using to do content replication/management that scale to > thousands of hosts/caches? even if i assume caching is as efficient, or > more so, than multicast, i'm still just trading one set of > security/scalability concerns for others. caching is no more a silver > bullet than multicast. In case of simple replication _on the fly_ or translation _unicast to multicast_, this is the same from point of view of effieiency. But multicst suppose to do perlication at the L2 level, where you have no information about the context, about _time to expire_ (how multicast helps you to decrease traffic in case of AUDIO-ON-DEMAND_ if I ask some nw song, and you ask the same song 10 seconds later - but remember, such requests are no popular then _Live audio_ requests except some events). If case of _caching on the fly_ you have all L4 (not L3 but L4) information, it's flexible level and vendor can easily add _time to expire_ into his live stream. Just again, multicasting is the END of L4 ca”hing, not the beginning. And when I analyse existing network, I saw the useless of multicasting _except_ some special cases (such as some live streams in case of important events). And I think the idea _to start from multicsting_ was wrong from th first moment of time. You should END by multicasting - when you ahev a network of media sources, a network of media customers, the set of policies installed over the world - you can use multicasting locally to improve the local throughput. But try to build multicast network this days - the thouthand of hackers will be happy -:), and a lot of ISP refuse to cooperate... PS. I never saw the multimedia really need multicasting on the L2 level -:). But I see a lot of multimedia where L4 caching can improve quality dramatically. Every day. > > > >I think blaming vendors for inability to build products which run faster > >than the proven lower boundaries for the required kind of algorithms is, > >er, strange. > > i won't deny the potential scalability problems but i think your > generalizing/oversimplifying to say caching just works and has no security > or scalability concerns. It's amazing, but please name ANY securyty concern appeared due to WWW caching -:). It's not ideal solution (you can't cache SSL sessions, for example, through you can cache signed or crypted sessions - image PRP crypted multimedia session, for example), but I can't remember any security problem with it. > > -brett > > > > Aleksei Roudnev, Network Operations Center, Relcom, Moscow (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager) (+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)