>>> "Stephen Betts" <stephen.betts@Jalna7.co.nz> 11/24/00 11:49AM >>>
I think that you will find ping times are largely irrelavant, most
sites
block them and they have a low priority on the network / routers. I'm
sure
that this has been mentioned here several times in the past
I cannot ping anything (game site or host ) from the LAN here, yet all
the
games show ping times !!
This is because the games ping times are acutually calculated from
sending
mostly UDP (or TCP) packets across the internet. Again typically UDP is
a
not guaranteed for delivery and requires the application to re-transmit
the
data. TCP is slightly better in that the Network Layer will re-transmit
the
data and re-order the packets and if necessary request re-transmission
or
missing packets.
Anyway, I get actual ping times to xtra, paradise and jetstream-games
of 50
- 80 ms from my external adapter. I wouldn't complain about that.
International sites are typically nearer 200 ms so your gaming will
never be
as good as local
True it's a good ping compared to a dialup option, but when we're
talking high-speed options, aka cable, ISDN, walker wireless it's
nothing exceptional. Granted pings to overseas sites are higher that
national, but I'd say that gamers would be using the free-gaming realm
more than anything to play spacies over, this being national.
The corporate networks I have supported are lucky to get less than
100-125
ms AKL - WGL, and the international links are 400-500ms they also pay
2-5
times what ADSL costs for the privilage. (OK its not a fair comparison
but
you get the picture)
Hrm, I've been on a mate's network who can get ~15-25ms pings from Chch
to Welly and ~30-45 from Chch to Auckland. Pings over my DSL connection
going via Paradise.net then via Telstra to www.yahoo.com get about 80 ms
pings. You sure you're getting the service you paid for?
I guess running a business is not as important as killing people as
fast as
you can
It depends what perspective you look at it from. If you look at it from
the service provider's perspective, any customer is a good customer, so
whether they be running a business or fragging other gamers they are
paying customers.
Chris
-----Original Message-----
From: Charismo [mailto:charismo@xtra.co.nz]
Sent: Friday, 24 November 2000 02:44
To: adsl@unixathome.org
Subject: ADSL and interleaving
After a lot of research I discovered that what I wanted to do
apparently has
to be done at the DSLAM which is a pity, here's an article which I
think
many people may find interesting. If for example, I were to ask
telecom
nicely, would they do as other ISP's have done around the world and
remove
interleaving for just myself? Or at least reduce it to a much lower
level,
as I understand it Telecom New Zealand set it to 30 ms but I could be
wrong.
For a very prolific quake player I can tell you that 30 milliseconds
makes
all the difference. Ping is the *sole* reason why we have ADSL, there
are no
other solutions for where we live that are within our budget
(Palmerston
North) that come close, although I suppose if I was in Wellington I
could
simply get cable which sports 30 ms like pings... in any case I hope
some
lovely person from Telecom reads this and considers my request. If we
had to
sign something to get it done then we wouldnt' mind doing that ;). The
URL
is here: http://www.dslreports.com/shownews/205
<http://www.dslreports.com/shownews/205> , sorry for posting the whole
thing
here but I thought it would be more convenient.
In addition... this URL here leads me to believe that this can be done
on a
per customer basis, in which case if the customer is happy with the
change,
should it not be doable? http://www.dslreports.com/shownews/439
<http://www.dslreports.com/shownews/439>
Latency and Interleaving
For internet telephony or interactive applications such as remote
administration over a telnet session, latency is a key (and much
discussed)
attribute of the connection.
At the moment, the class of users most obsessed with latency would have
to
be the online gaming community. They are often buy entry level
residential
ADSL lines, with high download speeds, and are dismayed to read that
friends
on slower SDSL or IDSL lines are getting better ping times!
The first reaction of a disappointed gamer is to blame the ISP for
routing
inefficiencies or congestion, and although that is often the root
cause,
there is more to latency than just many hops and/or long distances.
ADSL modems commonly employ data Interleaving, which is a technique to
increase resistance to noise bursts on a line. Interleaving "smears"
out
micro bits of data (interleaves them over time) so that a short burst
of
signal destroying noise can only remove part of any given larger block.
Data
blocks reserve some space for error-correction data.. which can salvage
a
partially damaged block. Interleaving increases the chance that noise
on the
line will only cause partial damage, not complete loss. Thats the good
news.
The down-side of Interleaving is that it increases latency! this is
because
your little (say) quake movement packet is smeared out over several
packets
before it can be fully sent or fully received.
ADSL modems with typical Interleaving defaults can be 10-30ms behind
in
latency over equivalent speed SDSL modems... this means latency to any
point
for some ADSL modems can be at best 50ms! On the same setup, the
aforementioned SDSL modems that typically add only 10ms. So for use of
a
nearby server, ADSL Interleaving can be the biggest single source of
latency
that you have.
Unfortunately, there is little clear information supplied with, or
available
online, about what latency a given DSL modem or ISP connection has
built-in.
Some ADSL modems allow the user to turn off Interleaving, or turn it
down to
a narrow range, at the expense of possible data-loss on noisy lines.
The
Cisco 675, for example, has a full operating system inside it, and one
of
the attributes of the ether interface is Interleaving. See Randy
Lutton's
<http://www.users.uswest.net/~rlutton/ADSL/Misc.html> US West page).
Some
ISPs may be delivering this unit with Interleaving on, and some off.
In
other cases, it is the DSLAM (central office equipment) that has the
Interleaving set, and this cannot be changed.
Regards,
Anton Smith
Silicon Dreams Hardware News and Reviews,
<http://www.challenge-nz.com/silicon-dreams>
http://www.challenge-nz.com/silicon-dreams
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Received on Fri Nov 24 16:06:20 2000