Over the Horizon and Eliminating Layer 2? [Info on DEN]
By Susan Breidenbach
Network World, 5/4/98
A lot of piloting is going on this year on similar
projects, and analysts expect backbone upgrades
to go into full swing in 1999. "In two to three
years, the core of the network will be
routing-switch based, not router based," says
Forrester's Hannigan.
The new generation of products has pushed the
envelope out enough that bandwidth and prices
are not a big story anymore. "We're getting to the
point where real value is not bigger and faster but
more intelligent and more software-aware," says
Fred McClimans, chairman and CEO of Current
Analysis, Inc., a consultancy in Sterling, Va.
Instead, the focus should shift to incorporating
services - directories and firewalls, for example -
into the switches.
"The big emphasis will be on prioritization,"
McLean says. "Not for video or voice, but to
make sure that your SAP traffic gets through no
matter what else is going on."
Increasingly, management tools should be
leveraging directory services. To date, network
management has really been device management.
"Now you can manage class of service and QoS
and align management policies with the particular
needs of your business environment," says Clint
Ramsay, vice president of marketing for 3Com
Corp.'s enterprise systems division in
Boxborough, Mass.
In the Infonetics survey of high-speed LAN
users, three-fourths of respondents said they
would require QoS capabilities by 2000.
However, most of them plan to provide it by
over-provisioning their networks.
While QoS gets a lot of hype from vendors, it
doesn't seem to be much more than a check-off
item for users right now. "We're not looking at
QoS, but rather at using policy-based
management to control access to network
resources," says Frank Bielecki, network
manager at Sandia National Laboratories in
Livermore, Calif.
A number of experts expect this functionality to
be provided through Directory Enabled
Networks (DEN).
"This is a radical new approach to managing
bandwidth," says Sam Alunni, a vice president at
Sterling Research, Inc. in Sterling, Mass. Policies
are established in a single directory that switches
can access. The switches provision network
resources based on profiles set up for users and
applications.
"With DENs, you start to get the same degree of
control over frame-based networks that you used
to have to go to ATM to get," Alunni says.
Four nines
Networks should also get more reliable as
functions are moved into silicon and there are
fewer parts. After all, the network component
that fails most often is the routing software.
"We will finally see high availability for the
masses," says LANNET's Bendori. As this
approaches the 99.99% availability requirement
of the Bellcore Network Equipment-Building
System standard, it will enable business-quality
voice over IP and finally unlock the tremendous
potential of computer-telephony integration.
Layer 3 intelligence will get more democratic as
well. It is expected to spread to the wiring closets and even out to the edges as WAN links go beyond E-1 speeds.
"Intelligence is getting cheap, so put it in the
closet," says Douglas Hill, co-founder of Xylan
Corp. in Calabasas, Calif.
When desktops are attached to Layer 3
switches, all sorts of possibilities open up. These
include user-authentication capabilities that
enable the network
to reconfigure itself based on the identity of the
user; end-to-end QoS; and much more granular
directory-enabled networking and intelligent
multicast distribution.
The Resource Reservation Protocol (RSVP)
feature is being incorporated into Microsoft's
Windows desktop and needs to talk directly to a
Layer 3-aware device if it is to be useful. It is
difficult to implement end-to-end QoS via RSVP
if there is a Layer 2 device between the
Windows machine and the rest of the network.
Eliminating Layer 2?
Vinod Bhardwaj, the inventor of the first Ethernet
switch, can see carrying things even further by
putting a router at every port and eliminating
Layer 2 altogether. Assuming the world
converges on IP and silicon prices continue to
fall, he thinks it could happen in three to four
years.
"Routing is a superset of switching, so it has
everything the network requires," says Bhardwaj,
now president and CEO of ControlNet, Inc., a
high-speed networking start-up in Campbell,
Calif. "You would just need a NIC and a router."
Bhardwaj's vision isn't out of the realm of
possibility. In fact, it dovetails nicely with the
TCP/IP protocol stack, in which Layer 2 is
equivalent to OSI's Layer 3 and there is no
separate data-link layer.
First, though, the routers will have to get a lot
more intelligent, says Mary Petrosky, senior
analyst at The Burton Group in Salt Lake City.
Otherwise, the configuration and administration
of all those routers would be prohibitive.
"In ATM, if you have a network with some
155M switches and you drop a new 622M
bit/sec box into the core, they will all find each
other and update their tables and learn the new
topology," Petrosky says. "Routers don't do that
at this point."
Self-configuring routers that can fit into a single
switch port at an affordable price? They're not
exactly on the horizon, but with the speed at
which switching has progressed thus far, who
would say it can't happen?
Intro and What's in a Name
Prospects for ATM and Wrong Assumptions
Winners & Losers and The next Cisco?
The entire report in a single file
Feedback | Network World, Inc. | Sponsor Index
Marketplace Index | How to Advertise | Copyright
Home | NetFlash | This Week | Industry/Stocks
Buyer's Guides/Tests | Net Resources | Opinions |
Careers
Seminars & Events | Product Demos/Info
Audio Primers | IntraNet |
