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Speed Matters: Taking Control! |
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SPEED Everyone
wants it! Nowadays, it seems you just can't get enough of it,
and there is no such thing as too fast! Fast cars, fast
women, fast food, fast lifestyles, fast servers, fast machines,
and fast sites. The faster the better, right? There
sometimes seems to be no better compliment than, "Man, he's
got a fast site!" No mention of content.
How many times have I heard someone tell
me, "Good site, but it's too slow." Hmmm, many times.
Where does one draw the line, anyway,
between a good looking site, one with good content and nice
graphics, and pages which happen to be, for some folks, "a
bit big?"
How big is too big? How slow, too
slow? How can I speed things up? And does it really matter?
First the last. Yes, in fact it does matter.
Speed matters. Size influences speed, so size matters, too.
How long are surfers willing to wait for
a page to download? Well, it depends on the surfer, doesn't
it? But is there an heuristic - a rule of thumb - that we
can build our pages around? Sure, I'll give you one. 15 to
20 seconds. How's that sound? Why?
The 15 to 20 seconds rule goes back a
long way. Back in the days when a 14.4 modem was most common
and the 28.8 modems were just coming out, it was often stated
that home page sizes should be kept to 10 to 15K, and not
more than about 20K (including both the HTML for the page
as well as any images on the page). To make a rough calculation
on how fast a page will load for a given modem speed, divide
the modem speed by 10 and the result is the approximate number
of characters per second that the modem will handle.
So, for a 14.4 modem, this gives a result
of 1,440 characters per second. Thus, a 14.4 modem will load
a 15K page (15,360 bytes) in just a fraction over 10 seconds
(15,360/1,440 = 10.66); and a 20K page will load in just under
15 seconds. And that is where the 15 to 20 seconds came from.
Since almost everyone now runs at 28.8 or higher, page sizes
of 20 to 40K are not unreasonable at all. In fact, this is
a good size range and another rule of thumb for you.
Accordingly, a 50K page will load in 17.36
seconds (under optimal conditions) with a 28.8K modem; but
since more and more people have upgraded to a 57.6K modem,
a 50K page would take only half this time, or 8.68
seconds - not bad! So can we increase our page sizes then?
Up to you, but for now I'm going to stay with and recommend
a new heuristic (as far as I know): the 15-50 rule of thumb:
15 seconds and 50K.
Remember we have to bear in mind the poor
people with slow modems and slow Internet connections around
the world who are sitting around waiting for your page to
download. The bottom line is, "Do you want to risk losing
them because they got tired of waiting and surfed on?" I don't.
I'd also think twice before putting up
a big, fancy slow-loading Flash page. You can only get so
many seconds, and so many clicks (3?), out of your average
surfer. Attention spans are not on the rise, ladies and gentlemen!
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Web Hosts How
much does the speed of my site have to do with my web host?
Good question. This really depends
on the connection your web host has with the Internet. Many
web hosting companies buy their connections from large backbone
providers like UUNET. At the least, they should have T3 lines
(on which more soon).
Many companies have more than one connection
to the Internet, which is called "multi-homing." This allows
people to still be able to access your site even if one connection
fails. Good web hosts should also have backup power supplies
(like diesel generators, etc.); do regular backups of their
web servers; and, very importantly, have real people on site
who know how to fix things quickly when they go wrong which
they inevitably will!
Speed from the host also depends on how
many web sites they put on each of their servers. If you happen
to be on a server with only 100 web sites on it, versus
one with 200 web sites running, your site is going to run
more quickly with the first server. This is a good question
to ask your potential web hosts; i.e., "how many sites (and
what kind of sites!) are you running on your servers?" You
can guess quite easily what kind of sites are going to be
high-traffic, and which ones would not be receiving so many
hits.
OK, getting down to brass tacks, what's
all this T-1/OC-3 business mean, anyway? It's not that complicated,
really. Web hosting companies (as a rule) connect to the Internet
through "T" (Transmission), "OC" (Optical Carrier), and/or
"DS" (Digital Signal) lines. Many smaller web hosts still
use T1's to connect your site to the world at a rate
of 1.544 megabits per second (Mbps - on which more later).
The big, fast guys use redundant, multiple OC3 (155.52
Mbps) lines to offer their clients the bandwidth they need
for multiple user sessions on their site(s) at any given time.
The best web hosts today use these "redundant"
lines to ensure that customers' sites remain up and active,
even if their primary Internet connections are temporarily
unavailable. It's a good idea to check which hosts offer backup
connections fast enough to maintain your site's performance
in case of a primary line failure.
When you search for a company on HostSearch
to meet your criteria, your search results will contain a
link to much of this information about different web hosts,
so you can compare and make an informed decision.
In addition to offering the fastest network
connections possible, a web host should provision its lines
and circuits to use less than fifty percent of available bandwidth.
Overburdened network connections will often result in poor
site performance; in fact, a lightly-used T1 line will
transfer data faster than an overused T3 connection
(see table below). Again, be sure to ask potential web hosts
about their network capacity and utilization to be sure that
your site will benefit from the fast network connections they
may have advertised. |
Connectivity Now,
to address those techno terms. Most people connect to the Net
from a modem (modulator-demodulator), which is
actually a relatively slow device. But your web host needs -
and will have - a significantly faster connection. The chart
below lists the terms that cover the different connection speeds
and how fast they are in kilobits, megabits, or gigabits per
second (Kbps/Mbps/Gbps). Speed is broken down into several categories.
A long time ago (in Net time), in the early days of the Internet
a whole decade ago, a T1 line was considered fast. Nowadays,
there are many types of connections a great deal faster.
| Connection
Type |
Speed |
| Modems |
14.4-56
Kbs |
| T1/DS1 |
1.55 Mbps |
| T3/DS3 |
43 Mbps |
| OC-1 |
51.85 Mbps |
| OC-3 |
155.52 Mbps |
| OC-12 |
622.08 Mbps |
| OC-24 |
1.244 Gbps |
| OC-48 |
2.488 Gbps |
Most hosting companies are connected to
the Internet by T1 & T3 lines. A T1 line can carry roughly
1.5 Mbps while a T3 can carry approximately 43 Mbps. A T3
connection provides a much larger amount of bandwidth and
speed availability. However, as mentioned above, you should
also check to see how many clients are hosted on any single
machine. If a server is overloaded, its performance will
be hindered - despite the highest high-speed Internet connection.
A T-3 is a dedicated telephone connection
supporting data rates of about 43 Mbps. A T-3 line actually
consists of 672 individual channels, each of which supports
64 Kbps (672 x 64 = 43008). T-3 lines are used mainly by Internet
Service Providers (ISPs) connecting to the Internet backbone
- and for the backbone itself. T-3 lines are sometimes referred
to as DS3 lines.
A T-1 is a dedicated telephone connection
supporting data rates of 1.544 Mbps. A T-1 line actually consists
of 24 individual channels, each of which supports 64 Kbps.
Each 64 Kbit/second channel can be configured to carry either
voice or data traffic. Most telephone companies allow you
to buy just some of these individual channels, known as fractional
T-1 access. T-1 lines are a popular leased line option for
businesses connecting to the Internet and for Internet Service
Providers (ISPs) connecting to the Internet backbone. The
Internet backbone itself consists of faster T-3 connections.
(T-1 lines are sometimes referred to as DS1 lines.)
A fractional T-1 line has one or more
channels of a T-1 service. A complete T-1 carrier contains
24 channels, each of which provides 64 Kbps. Most phone companies,
however, also sell fractional T-1 lines, which provide less
bandwidth but are also less expensive. Typically, fractional
T-1 lines are sold in increments of 56 Kbps (the extra 8 Kbps
per channel is used for data management). |
SPEED 2 (Sandra,
yes; Keanu, no) - SITE CONTROL
Some things you can control, others you
cannot. Unfortunately, there's not much you can do about general
Internet slowdowns. Do make sure you have a good web host
with high-speed connections and knock on wood for good luck.
However, you can take some fairly quick
and easy steps so that your site downloads as quickly
as possible.
We don't have room to go into all the
details here, but we can give you a couple pointers. We leave
you, for now, with these tips on how to make your pages smaller,
and thus, FASTER:
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Careful with those graphics. Sure,
everyone likes nice images, but if you can have your image
look just about as nice at 10K as it does at 80K, do it!
Many new graphics programs are designed with the Web in
mind, such as Adobe Photoshop 5.5 and up, Ulead PhotoImpact,
Corel Draw 8, and others. You can save images that look
nice at a reasonable size with these programs.
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Careful with your code. Some popular
WYSIWYG (what you see is what you get) web design programs
(like NetObjects Fusion and Dreamweaver) generate lots
of extra funky code (and add images like transparent GIFs)
and do unexpected things to your tables, like unnecessary
nesting, which dramatically increases the size of your
web pages.
If possible, edit your code, or at least
break up those big tables into a number of smaller ones, which
will at least appear to load faster. If you can't edit the
code yourself, consider using Dreamweaver or another program
to do it - they have some useful features such as "Clean Up
HTML" and "Clean Up WORD HTML" - always a good idea! - which
you might want to explore. |
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