Objectives and [EFM] Banana networks
- To: Geoff Thompson <gthompso@xxxxxxxxxxxxxxxxxx>
- Subject: Objectives and [EFM] Banana networks
- From: Roy Bynum <rabynum@xxxxxxxxxxxxxx>
- Date: Sat, 21 Dec 2002 19:40:22 -0600
- Cc: Hugh Barrass <firstname.lastname@example.org>, Sanjeev Mahalawat <email@example.com>, firstname.lastname@example.org, "'Mccammon, Kent G.'" <email@example.com>, Thomas.Murphy@infineon.com, Vipul_Bhatt@ieee.org, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org
- Sender: email@example.com
In the tread "Banana networks" you said: " I disagree here. I believe that
Ethernet is "broadband in the protocol sense." The difference is that it is
"flexibly broadband". Ethernet's main value as a trunking mechanism is its
ability to make its total bandwidth available to all comers based on their
instantaneous demand (up to the total available bandwidth, of course)."
By that reasoning, 10Base5 would also be considered as "broadband" and
should actually be named 10Broad5. Also by this reasoning, that all of the
existing Ethernet standards already support broadband $ubscribtion services
and there is nothing distinctive about 802.3ah in meeting the objectives
that would fit the criteria of "Distinct Identity" in that there already
are several 802.3 standards that meet the first objective.
Of course, in the actual wording of the initial objective, "Support
$ubscriber Access Network Topologies", the word "network" is used, not the
word "services". This limits the definitions to the physical facilities
and how they would be used.
I refer you to http://www.cisco.com/univercd/cc/td/doc/cisintwk/ita/b12.htm
, a glossary on a vendor's web site, under the term "broadband" there are
"Describes facilities or services that operate at the DS3 rate and above.
For example, a Broadband DCS makes cross-connections at the DS3, STS-1, and
STS-Nc levels. Similarly, Broadband ISDN provides about 150 Mb/s per
channel of usable bandwidth.", under one heading of "broadband", and
with another heading of "broadband":
"1. Transmission system that multiplexes multiple independent signals onto
"2. Telecommunications terminology: Any channel having a bandwidth greater
than a voice-grade channel (4 kHz)." (This is actually incorrect, since a
voice channel is referred to as "narrowband" and a T1 to DS3 is referred to
"3. LAN terminology: A coaxial cable on which analog signaling is used. An
RF system with a constant data rate at or above 1.5 Mbps. Also called
wideband. Contrast with baseband." (Other glossaries make the distinction
that broadband signalling consists of multiple RF frequencies.)
Under the term "baseband" is:
"Characteristic of a network technology where only one carrier frequency is
used. Ethernet is an example of a baseband network. Also called narrowband.
Contrast with broadband."
Using these definitions, Ethernet, including 802.3ah qualifies as
"broadband" relative to the bandwidth, but does not qualify as "broadband"
in any other sense.
Since 802.3ah does not provide for multiple independent signals,
"channels", the physical facilities can not be "unbundled". This means
that 802.3ah will only support one $ubscription service provider, the owner
of the physical facilites, what ever diversity of services they may
offer. The ability for customers to link to different or multiple service
providers over the same facility is not supported. As such, 802.3ah is
specific to only the incumbent providers, or one specific provider, not the
industry as a whole. Any newly funded facility that has the political
will of supporting multiple service providers with equal access and
competition would NOT deploy EFM technology. In this, I would question
whether it meets the criteria of "numerous users" in that is only meets
the requirements of a limited number of users. (Remember that the "user"
here is a service provider not the customers of that service provider.)