In the fast-paced world of networking, technology is constantly
evolving to meet demands from business for greater bandwidth.
CW360.com selects five technologies that promise to play a major
role in tomorrow's network infrastructure designs.
With the explosion of the Internet and use of IP networking within
business, suppliers have been busy working on ways to make
networking cheaper and easier to deploy. That means users face a
number of fresh concerns.
First, the popularity of IP networking has resulted in a shortage
of IP addresses. Second, demand for greater bandwidth from
businesses has caused telcos to look at cheaper wide area
networking technologies. Businesses now using wireless LANS (WLANs)
face the prospect of running obsolete equipment as the current
802.11b standard for WLANs is superseded by 802.11a.
Finally, network suppliers are supporting an emerging standard for
power over LAN, which promises to make it easier for users to plug
their wireless devices into a network.
Networking with IP v6.0
IPv6 has been a target for the
IT industry for almost a decade now. Driving this standard has been
the recognition that IP addresses for public use are running out
and this is exacerbated by the increase in devices that need an IP
address. It also aims to address several significant shortcomings
with the current IPv4 standard.
The need for more address spaces is often cited as the primary
reason for moving to IPv6 although the change to the address space
is more than just adding a larger pool. The IPv6 address mechanism
is designed to allow addresses to be split into two parts, a unique
identifier for a device and a location of where that device is
connected to the network. In the mobile phone industry, this is
seen as being a big driver to control access and provide
localisation services. For corporate IT departments it would mean
that any device within a corporate network would be uniquely
identifiable. This could boost security as it would be possible to
track devices physically.
Versions of IPv6 exist for the leading operating systems and all
networking vendors are trialling their own IPv4/IPv6 bridges which
will be required during the transition from one standard to the
next. The major telecom operators are deploying IPv6 in their
network backbone and at EU level there are several projects to
install IPv6 on the inter-governmental network.
Equipment suppliers such as Cisco, Ascend and Nortel already
support IPv6 and leading network card vendors have been shipping
IPv6 drivers for some time. With the availability of IPv6/IPv4
bridges there is no reason why corporate network teams cannot
deploy IPv6 today in a staged deployment without affecting their
existing networks.
DWDM (dense wavelength division multiplex)
Optical
networking involves transmitting light down an optical fibre. In
DWDM, rather than use a single beam of light to transmit data, the
light is split into its constituent colours. Each colour (or
frequency of light) is then used individually to transmit data,
thereby increasing the amount of data a single optical fibre can
transmit.
This technology is being widely deployed by various telecom
carriers around the world. They see it as a significant way to
reduce the cost of telephony.
The cost of network expansion is substantially reduced by DWDM as
telcos do not have to lay new fibre. Other savings for operators
include lower management costs and fewer points of failure. With
mass-market suppliers such as Intel developing optical components
equipment costs are set to fall dramatically. For the user the cost
of bandwidth provided over DWDM is expected to fall as a
consequence.
One of the advantages of DWDM is that it is protocol independent
which allows operators to move voice and data across the same
network. For operators building large scale Virtual Private
Networks (VPN), DWDM allows them to provision services to several
customers over the same fibre without risk of compromising
security.
Power over LAN
Power over LAN (POL) uses network cables
to transmit electricity over a standard local area network. Its
primary use is for providing both power and data to network devices
using just a single cable. One of POL's attractions is that it
allows users to install network devices such as wireless network
access points in areas where there is no existing power, such as in
roof spaces. A standard for POL is being developed by the IEEE
802.3af committee. This is aimed at network equipment running at
10Mbit/s and 100Mbit/s using standard category 5 cabling. As a
result users should not need to install or change existing cabling
in order to take advantage of POL. However, there may be problems
with certain types of network equipment such as hubs and patch
panels.
The standard limits the amount of power that can be delivered to
just 15.4W (44-57v), which some suppliers believe is ample to run a
large number of network devices including, potentially, charging
laptop computers. However, there are suggestions from some wireless
suppliers that more needs to be done to ensure protection against
surges and overheating of devices, especially if they are placed in
areas that are difficult to monitor.
Suppliers such as PowerDsine, Cisco, Symbol, 3Com, Ericsson, Agere
(Proxim) and Intel are currently shipping POL enabled equipment.
Providing support for POL will require network equipment
manufacturers to make some changes to their existing products. So
it is likely, therefore, that until there is some demand from users
smaller suppliers will wait and see.
802.11g Wireless LAN
802.11g is an attempt by the IEEE
standards group to bring together two wireless standards. Its aim
is to create a high-speed network that will be backwardly
compatible with existing network equipment. The technical challenge
for the standard is that 802.11g needs to support the two existing
wireless WAN technologies: 802.11a and 802.11b, which use two,
separate radio frequencies. The 802.11g standard proposes a single
radio frequency. If successful, existing 802.11b users will have a
transition path to high-speed (>50Mbit/s) wireless networking
without having to replace their existing wireless
infrastructure.
With 802.11a products now being rolled out, suppliers are unlikely
to support another wireless standard so soon. The industry is only
now starting to deploy wireless access points that support the two
existing standards - 802.11a and 802.11b. No suppliers are yet
supporting 802.11g. As and when products become available it is
likely manufacturers such as Cisco, Symbol and Agere, who are
shipping 802.11a today, will lead the way with 802.11g
products.
Networking over power lines
During the early push to get
broadband deployed, the idea of transmitting data over power lines
was extensively explored. The technology worked by using the
electrical distribution network to provide Internet access as well
as electricity. It required a box placed at the end-user's premises
to separate electrical signals from data.
The speed that users can expect to receive is around 1Mbit/s which
is comparable to the highest speed ADSL and Cable connections
today. So far, the take up of Digital PowerLine - as the industry
calls it - has been extremely limited with the USA and Germany
being the two biggest markets. One of the reasons for this is
persuading consumers that it is safe and can compete against
existing technologies. Prior to wireless LAN technology Digital
PowerLine was positioned as a way to create small office and home
LANs. This failed due to price and electrical safety
concerns.
Industry body the HomePlug Powerline Alliance (
www.homeplug.com)
boasts around 30 adopters of the technology, among them Ericsson,
Linksys, HP and Accton.