view images from CCTV cameras via the internet
Modern CCTV recorders have
the ability to act as a web server. DVRs like the DMR4-MPEG4 model have a LAN
(Local Area Network) port as standard, hence allowing them to be connected to a
network for both local and remote viewing.
A simple network can be
established by connecting the DVR directly to a PC.
The DMR4-MPEG4 recorders
are supplied with a simple to use viewing software.
Once the programme has
been loaded on to the PC you can view live and recorded images from the DVR or
control most functions of the DVR. Recorded images can be saved to the PC.
You will only be able to
view the images from the connected PC.
A more useful
configuration can be obtained using a router. For example, a 4 port router will
allow the connection of 1 DVR and up to 3 computers. Each computer can then
access the DVR data.
A broadband router with a
live internet connection would allow connection from a remote PC.
Performance Across a Network Connection
The picture quality and
smoothness of the images when viewed over a LAN will usually be very good.
When viewing images over a
WAN (Wide Area Network) the performance of the internet connection is the
It is important to
understand the type of internet you are using.
Typically an ADSL or
Broadband service will be used.
ADSL stands for Asymmetric
Digital Subscriber Line. In simple terms this means the download connection and
the upload connections do not have the same capacities.
The download connection is
used to download information from a web server connected to the internet. You
may have a broadband connection with an 8Mbps capability (8 Million bits per
The upload connection is
always of a lower capacity, typically 256Kbps or 512Kbps. Check with your
Internet Service Provider (ISP) what type of service is available.
Alternatively, a DSL
connection can be purchased which will offer much higher capacities but at
greatly increased prices.
For most purposes an ADSL
connection will give usable results.
Understanding Static and Dynamic IP Addresses
IP networks work by each
connected device having an IP address. A broadband router will have 2 IP
address, one for the internal or LAN side and one for the WAN side.
For example the LAN side
devices, your PC and the DVR could have address as follows:
Router LAN side:
These are static IP
addresses in that they do not change.
The WAN side of the router
is assigned an IP address by your ISP and may be either static or dynamic.
The current Internet
Protocol system cannot cope with the high demand for static addresses so may
ISPs now provide dynamic IP addresses. This is achieved by your router
requesting an IP address from the ISP when it is powered on. The ISP assigns an
unused address. When you surf to any web site your IP address is sent as the
location to which the requested pages are be returned.
Most ISPs operate a
contention ratio system of current users to available internet connections. This
may be something like 30:1 which means there is only one internet connection
available for every 30 subscribers. Not all subscribers are online at the same
time so this is a workable system. In periods of inactivity your router will
temporary disconnect from the ISP but reconnect when a new web site is
requested. A new IP address will now be allocated. This process will appear
seamless to the user with no perceived loss of service.
To access the DVR from a
remote location you will need to know the WAN side IP address of the router
connection. With a dynamic IP address system this will be unknown. There is a
method to overcome this using a setup called DDNS
(Dynamic Domain Name Server).
More about this later.
Step Instructions To Connect a DMR4-MPEG4 Digtal Recorder to a Local a Wide Area
These instructions are
based on the DMR4 DVR but the general principal can be applied to most DVRs.
First steps – make the
Connect a suitable video
feed to the channel 1 input on the rear of the DMR4
In order to correctly
configure the DMR4, it must initially be connected directly to a PC or Laptop
using a CAT 5 patch lead. At this stage it should be a cross-over cable
(not a straight thru).
The default DMR4 IP
address is 192.168.1.10 The PC or Laptop needs to be configured so that its IP
address is in the same range as the I/P address of the DMR4.
The following steps show
you how to configure the PC or Laptop with an IP address of 192.168.1.2
The following steps show
configuration using Windows XP although configuration is similar for other
versions of Windows.
Open Control Panel
(start – settings – control panel) and double click Network Connections.
Double click the Local Area Connection
and select properties.
1. Select Internet Protocol
(TCP/IP) and then click on the Properties button.
The TCP/IP Properties dialogue lets you enter the TCP/IP address details.
2. Select the Use the following IP
address button and enter 192.168.1.2 in the IP address box. Select the
Subnet mask box and enter 255.255.255.0
Click OK and exit right
out of control panel
Note: Windows XP
will take around 30-60 seconds to set the new network settings – all other
versions of Windows will require a system restart
To test that the DMR4 is
properly connected, click Start – Run and enter ‘COMMAND’ in the box that
appears. Click OK and a black command prompt window should appear.
Type the following command
and press enter
You should see a screen
similar to the following:
This indicates that the PC
is communicating successfully with the DMR4. If you see ‘Request timed out’ or
other error message, this means there is either a problem with the patch lead or
the network configuration is incorrect - work through the above configuration
steps again to check for errors.
configuration of the Video Web Server software
Once you have established
a connection, insert the CD supplied with the DMR4 and install the video server
Once the software has
installed, double click on the desktop Video Web Server icon to run it.
The default user name and
password is set to admin / admin (case sensitive!). Enter these and the IP
address of the DMR4 as above. The Web port should be left at 80. Click OK and
the main DMR4 screen should appear.
this stage it is useful to familiarise yourself with the various functions and
configuration settings available within the web server software.
Advanced configuration steps
The above configuration
allows simple remote viewing and control on a standalone system. For
connectivity to existing networks or broadband routers etc., further
configuration is required.
To integrate the DMR4
with an existing network and broadband router
Note: at this point, the DMR4 should still be connected to a standalone PC and
not to the network.
The first step is to
gather information about the existing network setup (principally the IP address
range and whether the network uses static or DHCP IP address allocation)
If the network uses static
I/P addresses, locate a free I/P address that can be assigned to the DMR4 – in a
static IP setup, IP addresses are usually configured in sequence, the first
generally being 192.168.1.1. In this case, it’s fair to assume that an address
higher up the range is free – for example, in a network of 25 PCs, I/P address
192.168.1.90 is likely to be free. Double check that an IP address is free by
‘pinging’ it as detailed above. The procedure is similar for a DHCP setup –
determine the range of IP addresses that the DHCP server issues and choose an IP
address for the DMR4 that is outside this range. If you are unable to determine
the DHCP range, following the steps for a static IP network should give a usable
The subnet mask also needs
to be determined. The easiest way to do this is to open a command prompt on one
of the network PCs (Start – Run – ‘COMMAND’ – OK), type ‘IPCONFIG’
and press enter.
Amongst other information,
the subnet mask will be given – make a note of this.
Finally, the I/P address
of the router is required.
Log in to the DMR4 and
open up the configuration screen:
Enter your chosen IP
address in the Server I/P box and the subnet mask in the Net Mask box. The
Gateway setting should be the same as the router IP address and the DNS can be
left blank as DNS is handled automatically by the router.
Finally, change the Web
Port value from 80 to 1528 (more about
this later), and click APPLY to save the changes.
At this point, the DMR4
can be connected to the network. When connecting to a router you need a
straight thru cable not a crossover cable.
To allow remote access to
the DMR4, a ‘routing table’ must be set up on the router – a routing table is
simply a small set of instructions that tells the router what to do with certain
types of incoming data.
In this case, the router
needs to be configured so that all incoming data on port 1528 is directed to the
IP address of the DMR4 – the steps needed to do this vary between different
manufacturers but is a basic feature of all routers and should be documented in
the router manual.
To allow end users to
remotely access the DMR4, they need the following information:
The ‘public side’ I/P address of
your router (this is the static I/P address provided by your ISP)
A suitable username and password.
The video server software CD
Alternatively some DVRs
like the DMR4 allows a connection through Internet Explorer. Details of this
type of configuration can be found in the user manuals.
Router Configuration and Port
This example is based on a Netgear DG834 router
but the principle can be applied to most broadband routers
Imagine the Netgear DG834 is split in to two
halves - one half is the private side which serves the local network. This
‘half’ of the router has its own IP address (typically 192.168.1.30) and other
devices (PCs, laptops, DVR etc.) that are connected to it will all have a unique
IP address of the form
Because this is a private network, it cannot be
accessed directly from the outside world.
The other imaginary half of the DG834G is the
public side - it also has its own IP address which is allocated to you by your
ISP and can either be static (it never changes) or dynamic (your ISP could
change it at any time). Because this is a public network, in theory, anyone from
the outside world who knows your public IP address can access the router and
your private network. But, because the router has a security firewall built in,
incoming traffic is severely limited to prevent this.
For this reason, you need to configure the
DG834 so that incoming traffic intended for the DVR is correctly routed instead
of being blocked - this is known as port forwarding.
You will notice on the DVR that in the network
setup section, there is also a port number. This could technically be any value
but you must avoid common Internet ports such as 80, 110, 25, 21 etc. In
general, the default value on the DVR is acceptable.
In this case, the DMR4 default port value is
1528 so a rule needs creating on the DG834 that channels all traffic coming in
on port 1528 to the DMR4.
This section assumes that you have already
established a successful connection locally. Logon to the DG834 and select
‘Services’ from the menu.
Click ‘Add Custom Service’ and enter the
Name: DMR4 (or any other name of your choice)
Start Port: 1528
Finish port: 1528
And click ‘Apply’
Then, create a firewall rule as follows:
Select ‘Firewall Rules’ from the menu. Under
the inbound services, click ‘Add’ and enter the following:
Service: DMR4(TCP:1528) – This is the service
you created earlier
Action: Leave at ‘ALLOW always’
Send to LAN server: 192.168.1.10 - This is the
IP address of the DMR4
Wan Users and Log settings can be left
And click ‘apply’ to add the new rule
Once the firewall rule is setup, anybody should
be able to access the DMR4 from the outside world, as long as they are using the
To configure the software, the IP address is
the public static IP address of your router and the port number in this case
will be 1528. The username and password must match those set up on the DMR4
How to configure a DMR4 with a
dynamic IP address
By the very nature of how
it works, the DMR4 must have a fixed I/P address. This address is issued to your
end users allowing them to access the DMR4 at any time over the Internet.
However, many Internet
Service Providers will not allocate a fixed IP address – this essentially means
that every time a broadband connection is established, the DMR4 will have a
different IP address. Unless the end users know this address, they will not be
able to access the DMR4.
circumstances, we always recommend that you use an ISP that provides a static
I/P address – if this is not possible for whatever reason, the following steps
provide a workaround.
One solution is to sign up
to a ‘DynDNS’ service.
DynDNS (Dynamic Domain
Name Server) works as follows:
Register your choice of domain
name with a suitable DynDNS provider – one provider is
www.dyndns.org. Your chosen domain could be something like
A software client must then be
installed on a PC that has access to your Internet connection (www.dyndns.org
list a number of suitable clients that you can use). Depending on which client
you choose, the package may be free of charge or you may have to pay a one off
charge before you can use the client.
Configure the client with your
chosen DynDNS domain name (e.g.
www.dmrnet.dyndns.org). The client software runs in the background and
continually monitors your IP address that has been allocated to you and passes
it to the DynDNS server database.
Reconfigure the video web server
software by entering the DynDNS name in the ‘server IP’ box instead of a fixed
Each time the video web server
software is run, the DynDNS server will convert the DynDNS domain name to the
current IP address of your DMR thus allowing them to connect at any time,
regardless of your current IP address.
Please note that these
instructions on using dynamic IP addresses are for information only – as the
services listed above are provided by third parties, we are unable to offer
product support and cannot be held responsible for issues arising from the use
of the services mentioned above.