IPv6 is coming
Based on current usage levels, it is anticipated that the current
blocks of available addresses under the current system, also called
IPv4, will be exhausted in approximately three years. To head this off,
a new proposal is in the final stages of approval. Known as IPv6, it
will probably provide the most benefit to broadcasters and
multicasters, due to enhancements to how IP handles audio and video
The major improvement IPv6 provides is its ability to serve 3.4
× 1038 addresses using 128-bit addressing contrasted to the measly 4
billion currently supported by IPv4 using 32-bit addressing. In theory,
IPv6 will provide enough addresses for every person on the planet and
still have room to grow almost infinitely. Routing IPv6 data will be
made simpler due to the elimination of the NAT protocol since each
device will have a unique address and address translation will no
longer be necessary. The virtually limitless availability of unique IP
addresses opens up the possibility of a wide variety of devices, not
just PCs or printers. It is expected that even common items, such as
appliances or automobiles, can now have their own IP addresses.
There are interesting possibilities for our industry as well.
Imagine transmitters, processing equipment and other peripheral
equipment all having IP addresses that could be interconnected from
anywhere in the world. Take this a step further and consider a
transmitter that takes all of its control and audio streaming
information through an Ethernet connection connected to a remote
control and audio processor in a different state. Do you see where this
IPv6 addresses are 128 bits long. There are 64 bits for the
network address and 64 bits for the host address. The host address is
derived from the unique MAC address given to the network interface
device. Optionally, they can also be generated sequentially. In
practice, the IPv6 address is written in a hexadecimal formal
consisting of eight groups with four hex digits.
IPv6 is ideal for streaming because the protocol defines three specific types of addresses:
Unicast — Basically point-to-point, typical of most applications.
Multicast — One-to-many recipients.
— A variation of multicast, only delivered to a single node than routed
to other nodes until it reaches the recipient(s).
A detailed discussion of IPv6 would fill volumes, but you need to be
aware that many governments and large organizations are starting the
transition process. Newer equipment might be software upgradeable but
some will need to be changed. Start identifying compatibility issues
now. Many manufacturers have information on their websites. Be aware
that only Windows Vista and Mac OS X 10.3 and above have native support
When it comes to establishing a hard connection between one or
more points, IP tunneling is the ultimate tool. Why should you care
about tunneling? Consider for example that you are trying to set up a
remote broadcast in another county, state or country. Using a dedicated
IP address might create problems with latency or possible loss of
connection. Utilizing an IP tunnel would establish a dedicated virtual
connection between the remote user and host, similar to any local
device and typically with improved performance.
The concept of tunneling is based on a process that packages
the primary IP packet inside another packet. The purpose of the outer
packet is to create a virtual physical connection between two networks
that encapsulates the real data packet.
Like everything in the IT world, there is a protocol (or set of
protocols) that make implementation possible. There are two primary
protocols that can be used to create an IP tunnel:
Point-to-point tunneling protocol (PPTP) may seem familiar from
back in the days of dial-up connections. Originally developed by Cisco
and later licensed to Microsoft, this became a standard communications
protocol to be included standard with later versions of MS Windows and
as such, became a popular protocol with dial-up hosting providers.
PPTP requires two separate connections — one connection
maintains the data path using another protocol called Generic Routing
Encapsulation (GRE). GRE manages the encapsulation process and
subsequently strips the encapsulation at the other end. The second
connection is used to initiate and maintain the GRE session.
Layer 2 Tunneling Protocol (L2TP) is a newer and more
feature-packed version created from a combination of PPTP and another
old protocol called Layer 2 Forwarding (L2F). The use of Layer 2 here
is deceiving in that it actually operates at the application layer
(Layer 5). It works by encapsulating the packet, payload (original
data) and header within a UDP (Universal Data Protocol) datagram.
Datagrams are basically a package containing a short message. For
example, a series of datagrams form the basis for streaming audio and
video technologies. The current version is L2TPv3 which provides
improved performance and compatibly with other transport services.
One more protocol you should know is called IPsec, which is
short for IP security. This is typically used in conjunction with a
tunneling protocol, particularly L2TP as a means to provide secure
authentication and encryption services. When the two protocols are used
together the protocol is called L2TP/IPsec.
In practice, the tunneling process begins by establishing the
virtual connection between the client and host systems. The
implementation of creating the VPN is typically done through software
and/or hardware applications. A popular example of IP tunneling is the
Virtual Private Network (VPN), which provides remote users the ability
to gain access to their internal network (Intranet) and network
resources (printers, etc.) as if they were connected in their offices.
The remote user initiates a typical VPN session with a software client
that requires you log in with your username, password, etc. The host
end of the VPN manages the task of accepting requests to establish the
connection and verifying the user login and security information. Once
the user information has been accepted the tunneled connected is
established and remains connected until either the user (or
administrator) chooses to stop it or the host system has provisions to
drop the connection when not in use for a preset amount of time.
While tunneling provides a better experience for the remote
user, it also offers a much higher level of security for the host
network since the connection can't be established without going through
some level of security check.
Creating a tunneled connection is easy or cheap (even free)
with the use of software applications easily downloaded from the Web.
Some of the more popular ones include Zebedee, Nest and Barracuda. A
Web search for “IP tunneling software” will direct you to these and a
host of other solutions you can use to create your own custom IP
tunnel. Most of these also have detailed user guides to help you
achieve your goal and make a handy addition to your new toolbox.
McNamara is president of Applied Wireless, Cape Coral, FL.