Videoswitch VDM - Manual (Page 21)

Videoswitch
VDM Digital Recorder
Vdm601t.doc
13
4 Remote Access
4.1 Configurations
The various standard remote access configurations are illustrated in the following diagrams.
4.1.1 PSTN
Standard telephone lines (PSTN) provide the lowest cost and easiest method of achieving remote viewing of
images. A VDM/PSTN (modem) module must be installed in the VDM and the PC must have a standard
internal (or external) modem fitted. A telephone socket is required both at the VDM and at the PC end.
Image update rates of around an image every two seconds are typical, depending on the image quality
selected in the VI-Connect remote access software.
The public telephone network is worldwide, and any number of PCs can access any number of VDMs on a
one-to-one basis.
VDM
+
VDM/PSTN
PC
+
PSTN MODEM
+
“VDM Connect”
PUBLIC
SWITCHED
TELEPHONE
NETWORK
(PSTN)
MODEM CABLE MODEM CABLE
4.1.2 ISDN
ISDN provides almost instant dialling and faster update rates than PSTN. A VDM/ISDN module must be
installed in the VDM and a VDM/ISDN/TA terminal adaptor must be attached to the PC. An ISDN socket is
required both at the VDM and at the PC end.
Image update rates of around an image per second are typical, depending on the image quality selected in
the VI-Connect remote access software.
The ISDN network is available in many countries (subject to regional variations), and any number of PCs
can access any number of VDMs on a one-to-one basis.
VDM
+
VDM/ISDN
VDM/ISDN/TA
PC
+
“VDM Connect”
INTEGRATED
SERVICES
DIGITAL
NETWORK
(ISDN)
CAT5 CABLE CAT5 CABLE RS232 (SERIAL)
CABLE
4.1.3 Ethernet Local Area Network (LAN)
Ethernet provides almost instant connection and faster update rates than ISDN. A VDM/ETHER-1 module
must be installed in the VDM and the PC must have an Ethernet card installed.
Image update rates of around four images per second are typical, depending on the image quality selected
in the Vi-connect remote access software. Local area networks (LANs) generally employ Ethernet hubs or
switches, and the VDM plugs into this in the same way as a PC. Standard CAT5 cables are used
throughout.