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Message Digest
Volume 29 : Issue 76 : "text" Format
Messages in this Issue:
Re: When is broadband broad enough?
Fwd: How Pandora Slipped Past the Junkyard
Re: Waiting for Verizon..
Re: Waiting for Verizon..
Defenition of Baseband, Broadband, and Carrier
Re: Waiting for Verizon..
Re: Waiting for Verizon..
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Date: Tue, 16 Mar 2010 16:49:01 +1100
From: David Clayton <dcstar@myrealbox.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: When is broadband broad enough?
Message-ID: <pan.2010.03.16.05.48.58.283102@myrealbox.com>
On Mon, 15 Mar 2010 21:17:30 -0500, Rob Warnock wrote: .......
> Yes, that article mentions "methods where two or more signals share a
> medium" as being one usage, in the narrow field of telephony network
> engineering, but it has never been and is not the dominate one.
Well, telephony network engineering was where I first encountered the term
"Broadband" and there was a very clear understanding of what it defined.
15 (or so) years later I again encountered it when xDSL was first rolled
out and it was initially used in an accurate manner when describing
services that had voice as well as data on the same medium. Since then -
IMHO - it has been hijacked for the various uses you have cited.
For this grumpy old ex-telco person it will remain as it was! ;-)
Come the revolution all these other whackers misusing it will be up
against the wall while I chuck old handsets in their general
direction......
--
Regards, David.
David Clayton
Melbourne, Victoria, Australia.
Knowledge is a measure of how many answers you have, intelligence is a
measure of how many questions you have.
Date: Tue, 16 Mar 2010 11:31:28 -0500
From: John Mayson <john@mayson.us>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Fwd: How Pandora Slipped Past the Junkyard
Message-ID: <6645152a1003160931q4cec63e7n8894cdea5c172113@mail.gmail.com>
On Mon, Mar 15, 2010 at 3:55 PM, T <kd1s.nospam@cox.nospam.net> wrote:
>> Please describe the service for the readers: is it an iTunes clone? I
>> mean, does it download audio files to your iphone for playing as if it
>> was an iPod, or do you get "streaming" audio via the cellular
>> connections?
>
> It is a web (Flash) based music player. You start by telling it a few
> artists you like. It then goes out and finds similar artists. I have
> about 15 liked arists and genres in my list and as John said, it's great
> at making recommendations.
It's more than just that. Â It's an audio streaming service. They have
clients for handheld devices such as the iPhone. Â My Squeezebox radio
includes Pandora software.
>
> Not advised for a corporate environment though. It is a bit of a
> bandwidth pig.
Which is why so many corporate IT departments block them.
John
--
John Mayson <john@mayson.us>
Austin, Texas, USA
--
John Mayson <john@mayson.us>
Austin, Texas, USA
Date: Tue, 16 Mar 2010 07:53:40 -0700 (PDT)
From: hancock4@bbs.cpcn.com
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Waiting for Verizon..
Message-ID: <5958a1d0-d767-4f32-b800-39478d8ca514@t41g2000yqt.googlegroups.com>
On Mar 14, 4:58 pm, Stephen Adler <adler@stephenadler-remove_this.com>
wrote:
> Hey guys... You may be interested in my latest vlogs... I call it
> "Waiting for Verizon"
Verizon, at&t, and others are all very large companies. They serve
communities all over the country, and various services, eg POTS voice,
broadband (ie DSL and fibre) and cellphone are provided by different
divisions. It seems there is a great deal of variation in service
quality provided depending on the carrier, geographic area, and the
type of service offered.
Accordingly, I'd like to suggest when discussing service issues, that
posters be specific as to the geographic area and service in question.
For myself, I've found Verizon offers excellent service and support
for POTS in PA and NJ. I suspect this is because both the service
techs and the business office are legacy Bell System operations with a
long record of good service in those states. Even if the employees
themselves were hired post-divesture, they were still trained by
people from the 'old school'.
However, I've found support for wireless and broadband to be not as
good. I suspect this is because many of the business people are more
sales oriented, working on commission under tough quotas with high
employee turnover, rather than service-oriented with rigorous
training. Unfortunately it seems that carriers today want to dump the
legacy attitude on focus on aggressive sales, even if it means sales
people promising rates and installations that aren't true.
Historically, Bell provided good service in PA and NJ. But some other
Bell territories, such as served by baby Bell NYNEX, did not have as
good a record.
Date: Mon, 15 Mar 2010 18:07:05 -0500
From: Tom Metro <tmetro+telecomdigest@gmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Waiting for Verizon..
Message-ID: <4B9EBD99.9010003@vl.com>
Stephen Adler wrote:
> Tom Metro wrote:
>> Didn't the difficulty you had in dealing with Verizon give you second
>> thoughts as to whether you can rely on them as an ISP?
> Yes... that's why I'm keeping my current Comcast service for at least a
> couple of weeks...
That's not quite what I meant.
The expectation for any modern broadband service is that it should have
excellent uptime and high reliability. The question is what happens when
something does break down the road. Perhaps something not as blatantly
obvious as a complete service outage, but instead packet loss, bandwidth
slowdowns, staled connections, DNS problems, etc. At this point you have
become fully dependent on the service, and you're now at the mercy of
the competence of Verizon support.
Have those of you that have been using FIOS for a while had positive
experiences in dealing with Verizon support for more subtle and highly
technical issues, or are you just crossing your fingers and hoping it'll
never come to that?
> I get symmetric 25/25 performance.
Was your testing just to confirm Verizon's claims, or did Verizon ever
give you reason to believe you might not see their claimed bandwidth?
(Of course I'm sure they have lots of "best effort" wishy-washy wording
in their contract, as no low-end ISP wants to commit to providing a
guaranteed bandwidth.)
>> Did you purchase business-class service? I assume yes, given your
>> mention of static IPs.
> yup.
You probably haven't had a need for this yet, but for others with
business-class FIOS, have you tried getting custom PTR records for your
static IPs?
> As best as I know, there is no port blocking and I can do anything I
> want. Maybe there is some fine print I didn't read?
If I was going to depend on an ability to run servers - even for
personal use - I'd want to be sure they were expressly permitted by the
contract.
> I think its around $100 something for the 5 static IPs.
Sounds about right. I see $110 for 25/25 Mbps with a 1 year contract.
http://smallbusiness.verizon.com/products/internet/fios_pricing.aspx
I guess my objection to their pricing has always been that they charge
an excessive premium for static IPs. (I wonder how that'll change when
IPv6 starts getting rolled out.)
Of course it's still a great bargain if you look at it purely from a
bandwidth perspective, and ignore that they offer the same thing with
dynamic IPs for $20 less.
I think the price difference used to be more, as they used to start the
business plans at $100 with non-symmetric bandwidth. Now I see the
slowest link you can get with a static IP is 25/25.
If only somebody like Speakeasy resold FIOS...
(At one time Galaxy (gis.net) was a FIOS reseller, and it looked like
there was going to be a competitive market of FIOS resellers, but it
hasn't materialized, and Galaxy has since dropped it. A Google search
for "fios reseller" turns up several hits, including a CA ISP that is
undercutting Verizon's prices. But the trick isn't necessarily to get a
better price, but a more competent support organization.)
-Tom
--
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/
Date: Tue, 16 Mar 2010 12:24:43 -0400
From: "AJB Consulting" <ajbcs.remove-this@and-this-too.frontier.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Defenition of Baseband, Broadband, and Carrier
Message-ID: <000801cac525$34ae9940$01fea8c0@dell8100>
Definition of "Baseband," "Broadband," and "Carrier"
In the thread entitled "When is broadband broad enough?", our esteemed
colleague in Australia, David Clayton, calls attention to the use of
the term "broadband," a word that seems to appear in every news report
concerning the internet and connectivity. The use of the terms
"baseband," "broadband," and "carrier" have always had a contextual
meaning, but more importantly, the definition seems to vary based on
who is using the term and why. I am fascinated by language, and
always observe word usages carefully whenever I read documents
published in different eras. In my mind, the first definition of
these three words is always the electrical one - but as David pointed
out, not everyone shares that view.
I have here an older (1930's era) copy of the venerable text
"Principles of Electricity as Applied to Telephone and Telegraph
Work," published in many editions during the last century by the Long
Lines Department of AT&T. The word "broadband" appears countless
times throughout this edition, but even in this unassailable text it
is not always used in the electrical engineering sense. In the
electrical sense, "broadband" would refer to a signal the spectral
energy of which occupies a broad frequency band, as the name implies.
How wide this spectrum must be to qualify as broad is open to some
debate, but in the case of any channelized FDM system where carriers
of different frequencies are transmitted simultaneously over the same
physical medium there can be no such debate - that's broadband. This
remains true even if the content of the multiple carriers was
originally just one channel of message content, split across multiple
modulated carriers. Thus, a typical xDSL stream carrying one channel
of user content, even flying solo on a "dry" copper pair, would
qualify as broadband by this definition.
But here is where semantics rears it ugly head. In that same text
(often referred to simply as "Principles"), a discussion of
time-division multiplexing of separate message channels of low speed
(telegraph) data into a single higher bitrate stream refers to this as
a "broadband" service. Electrically, this stream is anything but
broadband - in the case of a conventional alternate-mark encoded
bitstream (as this was), the actual electrical signal would appear on
an oscilliscope as square wave, albeit a somewhat phase-distorted one.
If you were to send all marks and no spaces, the square wave would be
quite perfect indeed - and have virtually all of its spectral energy
concentrated on a very specific frequency. This, electrically, is the
very definition of the narrowest of narrow bands, which is often
conflated with "baseband." The use of the word "broadband" to refer
to this TDM telegraph stream conforms to the definition David Clayton
was discussing, i.e. carrying more than one service, or in this case
multiple channels of message content.
The term "baseband" is equally subject to being defined based on
context, but even allowing for that, its very meaning seems to have
been construed in recent decades. Baseband, in the electrical sense,
originally referred to a message signal that had not been
"frequency-shifted." A good example of this would be a 1,000 hertz
audio tone carried by a standard voice band telephone line. The 1,000
hertz tone playing in your ear from the telephone receiver is of
course transduced directly from an electrical waveform of the very
same frequency carried on the copper pair. If you were to drop the
electrical signal on this copper pair into an old-style analog FDM
carrier system, it would be used to modulate a higher frequency
carrier wave, or, in VERY archaic language, "frequency-shifted out of
the base band." (This is not to be confused with frequency-shift
keying, a modulation scheme for radiotelegraph signals that is very
far removed from this discussion.)
These days, however, the term baseband has come to mean something very
different, particularly in relation to transport of digital message
content. Its early use in digital systems applied to any encoded
message stream in which the symbol rate (the true meaning of "baud")
was directly correlated to the actual bitrate of the message content.
Simplex telegraphy is an example of this. A more recent example would
be an RS-232 connection, in which the electrical signal state in each
symbol slot is directly correlated to a 1 or a 0 in the actual message
bit stream. In recent decades, however, ethernet over twisted pair
has become king for local area networks, and here is where markets
wield their power. The various popular flavors of twisted pair
ethernet all have names that contain the word "base," e.g., 100baseT.
Sure enough, the "base" is short for baseband, and this misnomer,
applied to twisted-pair ethernet at the beginning, has stuck. Putting
aside gigabit ethernet (which splits the message data stream across
more than one physical circuit), even lowly 10baseT is not actually
baseband in the electrical sense. Complex voodoo encoding schemes in
all versions of ethernet result in a symbol rate that is indeed lower
than the actual content bit rate. Thus, the use of the word
"baseband" here is strictly applicable only in the sense that David
referred to, i.e., it is used to connect a single node on a network,
or at least talk to only one node at a time over a given physical
connection. And of course, "baseT" is what everyone in the
marketplace calls it, which is all that really matters if you want to
do business with everyone else.
This brings us to the word "carrier," a word which often appears in
the same sentences as the words "baseband" and "broadband." This word
has the hardest life of all - in addition to the electrical meaning
and the number-of-channels of message content meaning, this word has
yet a third job, that of defining what business a company is in. In
the electrical meaning, "carrier" of course refers to a signal which
is modulated by the message signal to produce a complex transmitted
signal from which the message content can be demodulated at the
receiving end. There are too many ways of doing this to even mention,
and if you want a good lesson in carrier modulation you can ask your
favorite Ham radio enthusiast to explain it. This would be a good
first step, because you can't even hope to comprehend the various
schemes for doing this with digital message content unless you
understand the analogue signal techniques first. Too many textbooks
that attempt to explain digital system modulation schemes tend to
confuse encoding techniques with modulation. The two are often
hoplessly intertwined, such as with QPAM, but they are indeed separate
issues (and both are way beyond the scope of this article). An
exploration of the encoding and modulation schemes used for modern
digital content transport systems will lead the astute reader to one
conclusion: These systems are such a complex amalgam of techniques
developed over more than a century that it is pure folly to attempt to
describe any of them using only one word. This is probably the
biggest reason that these semantic debates will always be with us.
The second definition of "carrier" as it relates to the
number-of-channels of message content meaning is perhaps the most
common usage. Everybody is familiar with "T-carrier," the undisputed
king of digital transport of voice for decades. Electrically, a true
T1 is in fact a baseband signalling system, virtually identical to the
multiplexed telegraph channels described above. But everyone calls it
T-carrier because the single bitstream can contain as many as
twenty-four separate channels of message content, in effect,
"carrying" these channels. The name was applied from the very
beginning, and this has always made sense, especially when one
considers that it was developed as a replacement for N- and O- carrier
systems, which were "carrier" systems in BOTH the electrical sense and
the number-of-channels of message content sense.
The last definition of "carrier" is the business meaning - and this
may be the most important of all, because without Carriers (with a
capital "C"), we wouldn't be able to have this discussion. Carriers,
of course, are the service providers that carry all the content that
spews from our keyboards, cameras and mouths. Your phone service
provider is a Carrier, as is your cable TV compnay, ISP, etc. It is
from this meaning that we get the term "Carrier-grade equipment."
There is also a second, elevated class of Carriers - those who operate
long-haul networks that cross continents and oceans and whose
customers are in fact themselves Carriers. These Carriers never have
to deal with us lowly end-user customers, instead providing transport
for companies that do, making them Carrier's Carriers. This inspires
the following inevitable statement: "Carrier's Carriers carry
Carrier's content carefully and continuously on optical carrier." And
I suspect that somewhere, on a sunny beach where one of their undersea
cables meets land, there is a girl selling sea shells.
All comments to this article are welcome, even if they are to tell me
I got it all wrong.
Copyright 2010 A.J. Bennett. All rights reserved.
Copyright 2010 Telecom Digest. All rights reserved.
Jim Bennett
*********************************************************************
Speaking from a secure undisclosed location.
Date: Tue, 16 Mar 2010 19:50:09 -0400
From: Scott Ehrlich <srehrlich.remove-this@and-this-too.gmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Waiting for Verizon..
Message-ID: <4BA01931.9080702@speakeasy.net>
Speaking of Verizon vs Comcast, what is the overall quality of service
from both companies, and, technically, quality of voice service,
between service through Comcast's voice options and through FIOS?
I'd like to save money through a package deal, but I don't want to
have to have the demarc moved from its current location. Last I
heard, phone service had to be routed through a special box inside the
house using Comcast's method, and I don't want to have to rely on VOIP
should power/Internet service go down.
Insights welcome.
Thanks.
Scott
Date: Tue, 16 Mar 2010 18:09:13 -0700
From: Sam Spade <sam@coldmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Waiting for Verizon..
Message-ID: <ZYVnn.12546$ao7.993@newsfe21.iad>
hancock4@bbs.cpcn.com wrote:
>
>
> Historically, Bell provided good service in PA and NJ. But some other
> Bell territories, such as served by baby Bell NYNEX, did not have as
> good a record.
>
If I recall correctly, sometime in the early or mid 1970s New York
Telephone (I think that is what it was called) service standards fell to
all time lows in metro-NYC. I was there a lot in those days, and I
recall perhaps 50% of the pay stations in Manhattan being out of service.
If I recall correctly, inter-office trunks also fell in the dumpster,
more because of bad maintenance than growtth. Thus, the grade of
service also went into the dumpster.
But, no one could match General Telephone Company of California for
extremtly poor service in the 1970s, especially in the greater Los
Angeles area. It got so bad Pacific Bell complained behind the scenes
repeatedly to the California PUC how General's lousy tandem arrangements
were affecting Pacific's metro service in Los Angeles.
I personally felt the wrath of GT's then awful toll service.
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End of The Telecom Digest (7 messages)
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